linux/arch/powerpc/kernel/asm-offsets.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* This program is used to generate definitions needed by
* assembly language modules.
*
* We use the technique used in the OSF Mach kernel code:
* generate asm statements containing #defines,
* compile this file to assembler, and then extract the
* #defines from the assembly-language output.
*/
compat: Move compat_timespec/ timeval to compat_time.h All the current architecture specific defines for these are the same. Refactor these common defines to a common header file. The new common linux/compat_time.h is also useful as it will eventually be used to hold all the defines that are needed for compat time types that support non y2038 safe types. New architectures need not have to define these new types as they will only use new y2038 safe syscalls. This file can be deleted after y2038 when we stop supporting non y2038 safe syscalls. The patch also requires an operation similar to: git grep "asm/compat\.h" | cut -d ":" -f 1 | xargs -n 1 sed -i -e "s%asm/compat.h%linux/compat.h%g" Cc: acme@kernel.org Cc: benh@kernel.crashing.org Cc: borntraeger@de.ibm.com Cc: catalin.marinas@arm.com Cc: cmetcalf@mellanox.com Cc: cohuck@redhat.com Cc: davem@davemloft.net Cc: deller@gmx.de Cc: devel@driverdev.osuosl.org Cc: gerald.schaefer@de.ibm.com Cc: gregkh@linuxfoundation.org Cc: heiko.carstens@de.ibm.com Cc: hoeppner@linux.vnet.ibm.com Cc: hpa@zytor.com Cc: jejb@parisc-linux.org Cc: jwi@linux.vnet.ibm.com Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: mark.rutland@arm.com Cc: mingo@redhat.com Cc: mpe@ellerman.id.au Cc: oberpar@linux.vnet.ibm.com Cc: oprofile-list@lists.sf.net Cc: paulus@samba.org Cc: peterz@infradead.org Cc: ralf@linux-mips.org Cc: rostedt@goodmis.org Cc: rric@kernel.org Cc: schwidefsky@de.ibm.com Cc: sebott@linux.vnet.ibm.com Cc: sparclinux@vger.kernel.org Cc: sth@linux.vnet.ibm.com Cc: ubraun@linux.vnet.ibm.com Cc: will.deacon@arm.com Cc: x86@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: James Hogan <jhogan@kernel.org> Acked-by: Helge Deller <deller@gmx.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-14 04:03:25 +00:00
#include <linux/compat.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/suspend.h>
#include <linux/hrtimer.h>
#ifdef CONFIG_PPC64
#include <linux/time.h>
#include <linux/hardirq.h>
#endif
#include <linux/kbuild.h>
#include <asm/io.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/cputable.h>
#include <asm/thread_info.h>
#include <asm/rtas.h>
#include <asm/vdso_datapage.h>
#include <asm/dbell.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#include <asm/lppaca.h>
#include <asm/cache.h>
#include <asm/mmu.h>
#include <asm/hvcall.h>
KVM: PPC: Implement H_CEDE hcall for book3s_hv in real-mode code With a KVM guest operating in SMT4 mode (i.e. 4 hardware threads per core), whenever a CPU goes idle, we have to pull all the other hardware threads in the core out of the guest, because the H_CEDE hcall is handled in the kernel. This is inefficient. This adds code to book3s_hv_rmhandlers.S to handle the H_CEDE hcall in real mode. When a guest vcpu does an H_CEDE hcall, we now only exit to the kernel if all the other vcpus in the same core are also idle. Otherwise we mark this vcpu as napping, save state that could be lost in nap mode (mainly GPRs and FPRs), and execute the nap instruction. When the thread wakes up, because of a decrementer or external interrupt, we come back in at kvm_start_guest (from the system reset interrupt vector), find the `napping' flag set in the paca, and go to the resume path. This has some other ramifications. First, when starting a core, we now start all the threads, both those that are immediately runnable and those that are idle. This is so that we don't have to pull all the threads out of the guest when an idle thread gets a decrementer interrupt and wants to start running. In fact the idle threads will all start with the H_CEDE hcall returning; being idle they will just do another H_CEDE immediately and go to nap mode. This required some changes to kvmppc_run_core() and kvmppc_run_vcpu(). These functions have been restructured to make them simpler and clearer. We introduce a level of indirection in the wait queue that gets woken when external and decrementer interrupts get generated for a vcpu, so that we can have the 4 vcpus in a vcore using the same wait queue. We need this because the 4 vcpus are being handled by one thread. Secondly, when we need to exit from the guest to the kernel, we now have to generate an IPI for any napping threads, because an HDEC interrupt doesn't wake up a napping thread. Thirdly, we now need to be able to handle virtual external interrupts and decrementer interrupts becoming pending while a thread is napping, and deliver those interrupts to the guest when the thread wakes. This is done in kvmppc_cede_reentry, just before fast_guest_return. Finally, since we are not using the generic kvm_vcpu_block for book3s_hv, and hence not calling kvm_arch_vcpu_runnable, we can remove the #ifdef from kvm_arch_vcpu_runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-23 07:42:46 +00:00
#include <asm/xics.h>
#endif
#ifdef CONFIG_PPC_POWERNV
#include <asm/opal.h>
#endif
#if defined(CONFIG_KVM) || defined(CONFIG_KVM_GUEST)
#include <linux/kvm_host.h>
#endif
#if defined(CONFIG_KVM) && defined(CONFIG_PPC_BOOK3S)
#include <asm/kvm_book3s.h>
#include <asm/kvm_ppc.h>
#endif
#ifdef CONFIG_PPC32
#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
#include "head_booke.h"
#endif
#endif
#if defined(CONFIG_PPC_FSL_BOOK3E)
#include "../mm/mmu_decl.h"
#endif
#ifdef CONFIG_PPC_8xx
#include <asm/fixmap.h>
#endif
#ifdef CONFIG_XMON
#include "../xmon/xmon_bpts.h"
#endif
#define STACK_PT_REGS_OFFSET(sym, val) \
DEFINE(sym, STACK_FRAME_OVERHEAD + offsetof(struct pt_regs, val))
int main(void)
{
OFFSET(THREAD, task_struct, thread);
OFFSET(MM, task_struct, mm);
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 07:05:53 +00:00
#ifdef CONFIG_STACKPROTECTOR
OFFSET(TASK_CANARY, task_struct, stack_canary);
#ifdef CONFIG_PPC64
OFFSET(PACA_CANARY, paca_struct, canary);
#endif
powerpc/32: add stack protector support This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-27 07:05:53 +00:00
#endif
#ifdef CONFIG_PPC32
#ifdef CONFIG_PPC_RTAS
OFFSET(RTAS_SP, thread_struct, rtas_sp);
#endif
#endif /* CONFIG_PPC64 */
OFFSET(TASK_STACK, task_struct, stack);
#ifdef CONFIG_SMP
OFFSET(TASK_CPU, task_struct, thread_info.cpu);
#endif
powerpc/livepatch: Add live patching support on ppc64le Add the kconfig logic & assembly support for handling live patched functions. This depends on DYNAMIC_FTRACE_WITH_REGS, which in turn depends on the new -mprofile-kernel ftrace ABI, which is only supported currently on ppc64le. Live patching is handled by a special ftrace handler. This means it runs from ftrace_caller(). The live patch handler modifies the NIP so as to redirect the return from ftrace_caller() to the new patched function. However there is one particularly tricky case we need to handle. If a function A calls another function B, and it is known at link time that they share the same TOC, then A will not save or restore its TOC, and will call the local entry point of B. When we live patch B, we replace it with a new function C, which may not have the same TOC as A. At live patch time it's too late to modify A to do the TOC save/restore, so the live patching code must interpose itself between A and C, and do the TOC save/restore that A omitted. An additionaly complication is that the livepatch code can not create a stack frame in order to save the TOC. That is because if C takes > 8 arguments, or is varargs, A will have written the arguments for C in A's stack frame. To solve this, we introduce a "livepatch stack" which grows upward from the base of the regular stack, and is used to store the TOC & LR when calling a live patched function. When the patched function returns, we retrieve the real LR & TOC from the livepatch stack, restore them, and pop the livepatch "stack frame". Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Torsten Duwe <duwe@suse.de> Reviewed-by: Balbir Singh <bsingharora@gmail.com>
2016-03-24 11:04:05 +00:00
#ifdef CONFIG_LIVEPATCH
OFFSET(TI_livepatch_sp, thread_info, livepatch_sp);
powerpc/livepatch: Add live patching support on ppc64le Add the kconfig logic & assembly support for handling live patched functions. This depends on DYNAMIC_FTRACE_WITH_REGS, which in turn depends on the new -mprofile-kernel ftrace ABI, which is only supported currently on ppc64le. Live patching is handled by a special ftrace handler. This means it runs from ftrace_caller(). The live patch handler modifies the NIP so as to redirect the return from ftrace_caller() to the new patched function. However there is one particularly tricky case we need to handle. If a function A calls another function B, and it is known at link time that they share the same TOC, then A will not save or restore its TOC, and will call the local entry point of B. When we live patch B, we replace it with a new function C, which may not have the same TOC as A. At live patch time it's too late to modify A to do the TOC save/restore, so the live patching code must interpose itself between A and C, and do the TOC save/restore that A omitted. An additionaly complication is that the livepatch code can not create a stack frame in order to save the TOC. That is because if C takes > 8 arguments, or is varargs, A will have written the arguments for C in A's stack frame. To solve this, we introduce a "livepatch stack" which grows upward from the base of the regular stack, and is used to store the TOC & LR when calling a live patched function. When the patched function returns, we retrieve the real LR & TOC from the livepatch stack, restore them, and pop the livepatch "stack frame". Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Torsten Duwe <duwe@suse.de> Reviewed-by: Balbir Singh <bsingharora@gmail.com>
2016-03-24 11:04:05 +00:00
#endif
OFFSET(KSP, thread_struct, ksp);
OFFSET(PT_REGS, thread_struct, regs);
#ifdef CONFIG_BOOKE
OFFSET(THREAD_NORMSAVES, thread_struct, normsave[0]);
#endif
#ifdef CONFIG_PPC_FPU
OFFSET(THREAD_FPEXC_MODE, thread_struct, fpexc_mode);
OFFSET(THREAD_FPSTATE, thread_struct, fp_state.fpr);
OFFSET(THREAD_FPSAVEAREA, thread_struct, fp_save_area);
#endif
OFFSET(FPSTATE_FPSCR, thread_fp_state, fpscr);
OFFSET(THREAD_LOAD_FP, thread_struct, load_fp);
#ifdef CONFIG_ALTIVEC
OFFSET(THREAD_VRSTATE, thread_struct, vr_state.vr);
OFFSET(THREAD_VRSAVEAREA, thread_struct, vr_save_area);
OFFSET(THREAD_USED_VR, thread_struct, used_vr);
OFFSET(VRSTATE_VSCR, thread_vr_state, vscr);
OFFSET(THREAD_LOAD_VEC, thread_struct, load_vec);
#endif /* CONFIG_ALTIVEC */
powerpc: Introduce VSX thread_struct and CONFIG_VSX The layout of the new VSR registers and how they overlap on top of the legacy FPR and VR registers is: VSR doubleword 0 VSR doubleword 1 ---------------------------------------------------------------- VSR[0] | FPR[0] | | ---------------------------------------------------------------- VSR[1] | FPR[1] | | ---------------------------------------------------------------- | ... | | | ... | | ---------------------------------------------------------------- VSR[30] | FPR[30] | | ---------------------------------------------------------------- VSR[31] | FPR[31] | | ---------------------------------------------------------------- VSR[32] | VR[0] | ---------------------------------------------------------------- VSR[33] | VR[1] | ---------------------------------------------------------------- | ... | | ... | ---------------------------------------------------------------- VSR[62] | VR[30] | ---------------------------------------------------------------- VSR[63] | VR[31] | ---------------------------------------------------------------- VSX has 64 128bit registers. The first 32 regs overlap with the FP registers and hence extend them with and additional 64 bits. The second 32 regs overlap with the VMX registers. This commit introduces the thread_struct changes required to reflect this register layout. Ptrace and signals code is updated so that the floating point registers are correctly accessed from the thread_struct when CONFIG_VSX is enabled. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-25 04:07:18 +00:00
#ifdef CONFIG_VSX
OFFSET(THREAD_USED_VSR, thread_struct, used_vsr);
powerpc: Introduce VSX thread_struct and CONFIG_VSX The layout of the new VSR registers and how they overlap on top of the legacy FPR and VR registers is: VSR doubleword 0 VSR doubleword 1 ---------------------------------------------------------------- VSR[0] | FPR[0] | | ---------------------------------------------------------------- VSR[1] | FPR[1] | | ---------------------------------------------------------------- | ... | | | ... | | ---------------------------------------------------------------- VSR[30] | FPR[30] | | ---------------------------------------------------------------- VSR[31] | FPR[31] | | ---------------------------------------------------------------- VSR[32] | VR[0] | ---------------------------------------------------------------- VSR[33] | VR[1] | ---------------------------------------------------------------- | ... | | ... | ---------------------------------------------------------------- VSR[62] | VR[30] | ---------------------------------------------------------------- VSR[63] | VR[31] | ---------------------------------------------------------------- VSX has 64 128bit registers. The first 32 regs overlap with the FP registers and hence extend them with and additional 64 bits. The second 32 regs overlap with the VMX registers. This commit introduces the thread_struct changes required to reflect this register layout. Ptrace and signals code is updated so that the floating point registers are correctly accessed from the thread_struct when CONFIG_VSX is enabled. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-25 04:07:18 +00:00
#endif /* CONFIG_VSX */
#ifdef CONFIG_PPC64
OFFSET(KSP_VSID, thread_struct, ksp_vsid);
#else /* CONFIG_PPC64 */
OFFSET(PGDIR, thread_struct, pgdir);
OFFSET(SRR0, thread_struct, srr0);
OFFSET(SRR1, thread_struct, srr1);
OFFSET(DAR, thread_struct, dar);
OFFSET(DSISR, thread_struct, dsisr);
powerpc/32s: Fix DSI and ISI exceptions for CONFIG_VMAP_STACK hash_page() needs to read page tables from kernel memory. When entire kernel memory is mapped by BATs, which is normally the case when CONFIG_STRICT_KERNEL_RWX is not set, it works even if the page hosting the page table is not referenced in the MMU hash table. However, if the page where the page table resides is not covered by a BAT, a DSI fault can be encountered from hash_page(), and it loops forever. This can happen when CONFIG_STRICT_KERNEL_RWX is selected and the alignment of the different regions is too small to allow covering the entire memory with BATs. This also happens when CONFIG_DEBUG_PAGEALLOC is selected or when booting with 'nobats' flag. Also, if the page containing the kernel stack is not present in the MMU hash table, registers cannot be saved and a recursive DSI fault is encountered. To allow hash_page() to properly do its job at all time and load the MMU hash table whenever needed, it must run with data MMU disabled. This means it must be called before re-enabling data MMU. To allow this, registers clobbered by hash_page() and create_hpte() have to be saved in the thread struct together with SRR0, SSR1, DAR and DSISR. It is also necessary to ensure that DSI prolog doesn't overwrite regs saved by prolog of the current running exception. That means: - DSI can only use SPRN_SPRG_SCRATCH0 - Exceptions must free SPRN_SPRG_SCRATCH0 before writing to the stack. This also fixes the Oops reported by Erhard when create_hpte() is called by add_hash_page(). Due to prolog size increase, a few more exceptions had to get split in two parts. Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK") Reported-by: Erhard F. <erhard_f@mailbox.org> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Tested-by: Erhard F. <erhard_f@mailbox.org> Tested-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206501 Link: https://lore.kernel.org/r/64a4aa44686e9fd4b01333401367029771d9b231.1581761633.git.christophe.leroy@c-s.fr
2020-02-15 10:14:25 +00:00
#ifdef CONFIG_PPC_BOOK3S_32
OFFSET(THR0, thread_struct, r0);
OFFSET(THR3, thread_struct, r3);
OFFSET(THR4, thread_struct, r4);
OFFSET(THR5, thread_struct, r5);
OFFSET(THR6, thread_struct, r6);
OFFSET(THR8, thread_struct, r8);
OFFSET(THR9, thread_struct, r9);
OFFSET(THR11, thread_struct, r11);
OFFSET(THLR, thread_struct, lr);
OFFSET(THCTR, thread_struct, ctr);
#endif
#ifdef CONFIG_SPE
OFFSET(THREAD_EVR0, thread_struct, evr[0]);
OFFSET(THREAD_ACC, thread_struct, acc);
OFFSET(THREAD_USED_SPE, thread_struct, used_spe);
#endif /* CONFIG_SPE */
#endif /* CONFIG_PPC64 */
#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
OFFSET(THREAD_KVM_SVCPU, thread_struct, kvm_shadow_vcpu);
#endif
#if defined(CONFIG_KVM) && defined(CONFIG_BOOKE)
OFFSET(THREAD_KVM_VCPU, thread_struct, kvm_vcpu);
#endif
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
OFFSET(PACATMSCRATCH, paca_struct, tm_scratch);
OFFSET(THREAD_TM_TFHAR, thread_struct, tm_tfhar);
OFFSET(THREAD_TM_TEXASR, thread_struct, tm_texasr);
OFFSET(THREAD_TM_TFIAR, thread_struct, tm_tfiar);
OFFSET(THREAD_TM_TAR, thread_struct, tm_tar);
OFFSET(THREAD_TM_PPR, thread_struct, tm_ppr);
OFFSET(THREAD_TM_DSCR, thread_struct, tm_dscr);
OFFSET(THREAD_TM_AMR, thread_struct, tm_amr);
OFFSET(PT_CKPT_REGS, thread_struct, ckpt_regs);
OFFSET(THREAD_CKVRSTATE, thread_struct, ckvr_state.vr);
OFFSET(THREAD_CKVRSAVE, thread_struct, ckvrsave);
OFFSET(THREAD_CKFPSTATE, thread_struct, ckfp_state.fpr);
/* Local pt_regs on stack for Transactional Memory funcs. */
DEFINE(TM_FRAME_SIZE, STACK_FRAME_OVERHEAD +
sizeof(struct pt_regs) + 16);
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
OFFSET(TI_LOCAL_FLAGS, thread_info, local_flags);
#ifdef CONFIG_PPC64
OFFSET(DCACHEL1BLOCKSIZE, ppc64_caches, l1d.block_size);
OFFSET(DCACHEL1LOGBLOCKSIZE, ppc64_caches, l1d.log_block_size);
/* paca */
OFFSET(PACAPACAINDEX, paca_struct, paca_index);
OFFSET(PACAPROCSTART, paca_struct, cpu_start);
OFFSET(PACAKSAVE, paca_struct, kstack);
OFFSET(PACACURRENT, paca_struct, __current);
DEFINE(PACA_THREAD_INFO, offsetof(struct paca_struct, __current) +
offsetof(struct task_struct, thread_info));
OFFSET(PACASAVEDMSR, paca_struct, saved_msr);
OFFSET(PACAR1, paca_struct, saved_r1);
OFFSET(PACATOC, paca_struct, kernel_toc);
OFFSET(PACAKBASE, paca_struct, kernelbase);
OFFSET(PACAKMSR, paca_struct, kernel_msr);
#ifdef CONFIG_PPC_BOOK3S_64
OFFSET(PACAHSRR_VALID, paca_struct, hsrr_valid);
OFFSET(PACASRR_VALID, paca_struct, srr_valid);
#endif
OFFSET(PACAIRQSOFTMASK, paca_struct, irq_soft_mask);
OFFSET(PACAIRQHAPPENED, paca_struct, irq_happened);
OFFSET(PACA_FTRACE_ENABLED, paca_struct, ftrace_enabled);
#ifdef CONFIG_PPC_BOOK3E
OFFSET(PACAPGD, paca_struct, pgd);
OFFSET(PACA_KERNELPGD, paca_struct, kernel_pgd);
OFFSET(PACA_EXGEN, paca_struct, exgen);
OFFSET(PACA_EXTLB, paca_struct, extlb);
OFFSET(PACA_EXMC, paca_struct, exmc);
OFFSET(PACA_EXCRIT, paca_struct, excrit);
OFFSET(PACA_EXDBG, paca_struct, exdbg);
OFFSET(PACA_MC_STACK, paca_struct, mc_kstack);
OFFSET(PACA_CRIT_STACK, paca_struct, crit_kstack);
OFFSET(PACA_DBG_STACK, paca_struct, dbg_kstack);
OFFSET(PACA_TCD_PTR, paca_struct, tcd_ptr);
OFFSET(TCD_ESEL_NEXT, tlb_core_data, esel_next);
OFFSET(TCD_ESEL_MAX, tlb_core_data, esel_max);
OFFSET(TCD_ESEL_FIRST, tlb_core_data, esel_first);
#endif /* CONFIG_PPC_BOOK3E */
#ifdef CONFIG_PPC_BOOK3S_64
OFFSET(PACA_EXGEN, paca_struct, exgen);
OFFSET(PACA_EXMC, paca_struct, exmc);
OFFSET(PACA_EXNMI, paca_struct, exnmi);
OFFSET(PACA_SLBSHADOWPTR, paca_struct, slb_shadow_ptr);
OFFSET(SLBSHADOW_STACKVSID, slb_shadow, save_area[SLB_NUM_BOLTED - 1].vsid);
OFFSET(SLBSHADOW_STACKESID, slb_shadow, save_area[SLB_NUM_BOLTED - 1].esid);
OFFSET(SLBSHADOW_SAVEAREA, slb_shadow, save_area);
OFFSET(LPPACA_PMCINUSE, lppaca, pmcregs_in_use);
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
OFFSET(PACA_PMCINUSE, paca_struct, pmcregs_in_use);
#endif
OFFSET(LPPACA_YIELDCOUNT, lppaca, yield_count);
#endif /* CONFIG_PPC_BOOK3S_64 */
OFFSET(PACAEMERGSP, paca_struct, emergency_sp);
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 14:34:08 +00:00
#ifdef CONFIG_PPC_BOOK3S_64
OFFSET(PACAMCEMERGSP, paca_struct, mc_emergency_sp);
OFFSET(PACA_NMI_EMERG_SP, paca_struct, nmi_emergency_sp);
OFFSET(PACA_IN_MCE, paca_struct, in_mce);
OFFSET(PACA_IN_NMI, paca_struct, in_nmi);
powerpc/64s: Add support for RFI flush of L1-D cache On some CPUs we can prevent the Meltdown vulnerability by flushing the L1-D cache on exit from kernel to user mode, and from hypervisor to guest. This is known to be the case on at least Power7, Power8 and Power9. At this time we do not know the status of the vulnerability on other CPUs such as the 970 (Apple G5), pasemi CPUs (AmigaOne X1000) or Freescale CPUs. As more information comes to light we can enable this, or other mechanisms on those CPUs. The vulnerability occurs when the load of an architecturally inaccessible memory region (eg. userspace load of kernel memory) is speculatively executed to the point where its result can influence the address of a subsequent speculatively executed load. In order for that to happen, the first load must hit in the L1, because before the load is sent to the L2 the permission check is performed. Therefore if no kernel addresses hit in the L1 the vulnerability can not occur. We can ensure that is the case by flushing the L1 whenever we return to userspace. Similarly for hypervisor vs guest. In order to flush the L1-D cache on exit, we add a section of nops at each (h)rfi location that returns to a lower privileged context, and patch that with some sequence. Newer firmwares are able to advertise to us that there is a special nop instruction that flushes the L1-D. If we do not see that advertised, we fall back to doing a displacement flush in software. For guest kernels we support migration between some CPU versions, and different CPUs may use different flush instructions. So that we are prepared to migrate to a machine with a different flush instruction activated, we may have to patch more than one flush instruction at boot if the hypervisor tells us to. In the end this patch is mostly the work of Nicholas Piggin and Michael Ellerman. However a cast of thousands contributed to analysis of the issue, earlier versions of the patch, back ports testing etc. Many thanks to all of them. Tested-by: Jon Masters <jcm@redhat.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-09 16:07:15 +00:00
OFFSET(PACA_RFI_FLUSH_FALLBACK_AREA, paca_struct, rfi_flush_fallback_area);
OFFSET(PACA_EXRFI, paca_struct, exrfi);
OFFSET(PACA_L1D_FLUSH_SIZE, paca_struct, l1d_flush_size);
powerpc/64s: Add support for RFI flush of L1-D cache On some CPUs we can prevent the Meltdown vulnerability by flushing the L1-D cache on exit from kernel to user mode, and from hypervisor to guest. This is known to be the case on at least Power7, Power8 and Power9. At this time we do not know the status of the vulnerability on other CPUs such as the 970 (Apple G5), pasemi CPUs (AmigaOne X1000) or Freescale CPUs. As more information comes to light we can enable this, or other mechanisms on those CPUs. The vulnerability occurs when the load of an architecturally inaccessible memory region (eg. userspace load of kernel memory) is speculatively executed to the point where its result can influence the address of a subsequent speculatively executed load. In order for that to happen, the first load must hit in the L1, because before the load is sent to the L2 the permission check is performed. Therefore if no kernel addresses hit in the L1 the vulnerability can not occur. We can ensure that is the case by flushing the L1 whenever we return to userspace. Similarly for hypervisor vs guest. In order to flush the L1-D cache on exit, we add a section of nops at each (h)rfi location that returns to a lower privileged context, and patch that with some sequence. Newer firmwares are able to advertise to us that there is a special nop instruction that flushes the L1-D. If we do not see that advertised, we fall back to doing a displacement flush in software. For guest kernels we support migration between some CPU versions, and different CPUs may use different flush instructions. So that we are prepared to migrate to a machine with a different flush instruction activated, we may have to patch more than one flush instruction at boot if the hypervisor tells us to. In the end this patch is mostly the work of Nicholas Piggin and Michael Ellerman. However a cast of thousands contributed to analysis of the issue, earlier versions of the patch, back ports testing etc. Many thanks to all of them. Tested-by: Jon Masters <jcm@redhat.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-09 16:07:15 +00:00
#endif
OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id);
OFFSET(PACAKEXECSTATE, paca_struct, kexec_state);
OFFSET(PACA_DSCR_DEFAULT, paca_struct, dscr_default);
#ifdef CONFIG_PPC64
OFFSET(PACA_EXIT_SAVE_R1, paca_struct, exit_save_r1);
#endif
powerpc/64s/exception: remove bad stack branch The bad stack test in interrupt handlers has a few problems. For performance it is taken in the common case, which is a fetch bubble and a waste of i-cache. For code development and maintainence, it requires yet another stack frame setup routine, and that constrains all exception handlers to follow the same register save pattern which inhibits future optimisation. Remove the test/branch and replace it with a trap. Teach the program check handler to use the emergency stack for this case. This does not result in quite so nice a message, however the SRR0 and SRR1 of the crashed interrupt can be seen in r11 and r12, as is the original r1 (adjusted by INT_FRAME_SIZE). These are the most important parts to debugging the issue. The original r9-12 and cr0 is lost, which is the main downside. kernel BUG at linux/arch/powerpc/kernel/exceptions-64s.S:847! Oops: Exception in kernel mode, sig: 5 [#1] BE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted NIP: c000000000009108 LR: c000000000cadbcc CTR: c0000000000090f0 REGS: c0000000fffcbd70 TRAP: 0700 Not tainted MSR: 9000000000021032 <SF,HV,ME,IR,DR,RI> CR: 28222448 XER: 20040000 CFAR: c000000000009100 IRQMASK: 0 GPR00: 000000000000003d fffffffffffffd00 c0000000018cfb00 c0000000f02b3166 GPR04: fffffffffffffffd 0000000000000007 fffffffffffffffb 0000000000000030 GPR08: 0000000000000037 0000000028222448 0000000000000000 c000000000ca8de0 GPR12: 9000000002009032 c000000001ae0000 c000000000010a00 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: c0000000f00322c0 c000000000f85200 0000000000000004 ffffffffffffffff GPR24: fffffffffffffffe 0000000000000000 0000000000000000 000000000000000a GPR28: 0000000000000000 0000000000000000 c0000000f02b391c c0000000f02b3167 NIP [c000000000009108] decrementer_common+0x18/0x160 LR [c000000000cadbcc] .vsnprintf+0x3ec/0x4f0 Call Trace: Instruction dump: 996d098a 994d098b 38610070 480246ed 48005518 60000000 38200000 718a4000 7c2a0b78 3821fd00 41c20008 e82d0970 <0981fd00> f92101a0 f9610170 f9810178 Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-28 06:33:18 +00:00
#ifdef CONFIG_PPC_BOOK3E
OFFSET(PACA_TRAP_SAVE, paca_struct, trap_save);
powerpc/64s/exception: remove bad stack branch The bad stack test in interrupt handlers has a few problems. For performance it is taken in the common case, which is a fetch bubble and a waste of i-cache. For code development and maintainence, it requires yet another stack frame setup routine, and that constrains all exception handlers to follow the same register save pattern which inhibits future optimisation. Remove the test/branch and replace it with a trap. Teach the program check handler to use the emergency stack for this case. This does not result in quite so nice a message, however the SRR0 and SRR1 of the crashed interrupt can be seen in r11 and r12, as is the original r1 (adjusted by INT_FRAME_SIZE). These are the most important parts to debugging the issue. The original r9-12 and cr0 is lost, which is the main downside. kernel BUG at linux/arch/powerpc/kernel/exceptions-64s.S:847! Oops: Exception in kernel mode, sig: 5 [#1] BE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted NIP: c000000000009108 LR: c000000000cadbcc CTR: c0000000000090f0 REGS: c0000000fffcbd70 TRAP: 0700 Not tainted MSR: 9000000000021032 <SF,HV,ME,IR,DR,RI> CR: 28222448 XER: 20040000 CFAR: c000000000009100 IRQMASK: 0 GPR00: 000000000000003d fffffffffffffd00 c0000000018cfb00 c0000000f02b3166 GPR04: fffffffffffffffd 0000000000000007 fffffffffffffffb 0000000000000030 GPR08: 0000000000000037 0000000028222448 0000000000000000 c000000000ca8de0 GPR12: 9000000002009032 c000000001ae0000 c000000000010a00 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: c0000000f00322c0 c000000000f85200 0000000000000004 ffffffffffffffff GPR24: fffffffffffffffe 0000000000000000 0000000000000000 000000000000000a GPR28: 0000000000000000 0000000000000000 c0000000f02b391c c0000000f02b3167 NIP [c000000000009108] decrementer_common+0x18/0x160 LR [c000000000cadbcc] .vsnprintf+0x3ec/0x4f0 Call Trace: Instruction dump: 996d098a 994d098b 38610070 480246ed 48005518 60000000 38200000 718a4000 7c2a0b78 3821fd00 41c20008 e82d0970 <0981fd00> f92101a0 f9610170 f9810178 Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-28 06:33:18 +00:00
#endif
OFFSET(PACA_SPRG_VDSO, paca_struct, sprg_vdso);
#else /* CONFIG_PPC64 */
#endif /* CONFIG_PPC64 */
/* RTAS */
OFFSET(RTASBASE, rtas_t, base);
OFFSET(RTASENTRY, rtas_t, entry);
/* Interrupt register frame */
DEFINE(INT_FRAME_SIZE, STACK_INT_FRAME_SIZE);
powerpc/64: Fix stack trace not displaying final frame In commit bf13718bc57a ("powerpc: show registers when unwinding interrupt frames") we changed our stack dumping logic to show the full registers whenever we find an interrupt frame on the stack. However we didn't notice that on 64-bit this doesn't show the final frame, ie. the interrupt that brought us in from userspace, whereas on 32-bit it does. That is due to confusion about the size of that last frame. The code in show_stack() calls validate_sp(), passing it STACK_INT_FRAME_SIZE to check the sp is at least that far below the top of the stack. However on 64-bit that size is too large for the final frame, because it includes the red zone, but we don't allocate a red zone for the first frame. So add a new define that encodes the correct size for 32-bit and 64-bit, and use it in show_stack(). This results in the full trace being shown on 64-bit, eg: sysrq: Trigger a crash Kernel panic - not syncing: sysrq triggered crash CPU: 0 PID: 83 Comm: sh Not tainted 5.11.0-rc2-gcc-8.2.0-00188-g571abcb96b10-dirty #649 Call Trace: [c00000000a1c3ac0] [c000000000897b70] dump_stack+0xc4/0x114 (unreliable) [c00000000a1c3b00] [c00000000014334c] panic+0x178/0x41c [c00000000a1c3ba0] [c00000000094e600] sysrq_handle_crash+0x40/0x50 [c00000000a1c3c00] [c00000000094ef98] __handle_sysrq+0xd8/0x210 [c00000000a1c3ca0] [c00000000094f820] write_sysrq_trigger+0x100/0x188 [c00000000a1c3ce0] [c0000000005559dc] proc_reg_write+0x10c/0x1b0 [c00000000a1c3d10] [c000000000479950] vfs_write+0xf0/0x360 [c00000000a1c3d60] [c000000000479d9c] ksys_write+0x7c/0x140 [c00000000a1c3db0] [c00000000002bf5c] system_call_exception+0x19c/0x2c0 [c00000000a1c3e10] [c00000000000d35c] system_call_common+0xec/0x278 --- interrupt: c00 at 0x7fff9fbab428 NIP: 00007fff9fbab428 LR: 000000001000b724 CTR: 0000000000000000 REGS: c00000000a1c3e80 TRAP: 0c00 Not tainted (5.11.0-rc2-gcc-8.2.0-00188-g571abcb96b10-dirty) MSR: 900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> CR: 22002884 XER: 00000000 IRQMASK: 0 GPR00: 0000000000000004 00007fffc3cb8960 00007fff9fc59900 0000000000000001 GPR04: 000000002a4b32d0 0000000000000002 0000000000000063 0000000000000063 GPR08: 000000002a4b32d0 0000000000000000 0000000000000000 0000000000000000 GPR12: 0000000000000000 00007fff9fcca9a0 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 00000000100b8fd0 GPR20: 000000002a4b3485 00000000100b8f90 0000000000000000 0000000000000000 GPR24: 000000002a4b0440 00000000100e77b8 0000000000000020 000000002a4b32d0 GPR28: 0000000000000001 0000000000000002 000000002a4b32d0 0000000000000001 NIP [00007fff9fbab428] 0x7fff9fbab428 LR [000000001000b724] 0x1000b724 --- interrupt: c00 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210209141627.2898485-1-mpe@ellerman.id.au
2021-02-09 13:59:20 +00:00
DEFINE(SWITCH_FRAME_SIZE, STACK_FRAME_WITH_PT_REGS);
STACK_PT_REGS_OFFSET(GPR0, gpr[0]);
STACK_PT_REGS_OFFSET(GPR1, gpr[1]);
STACK_PT_REGS_OFFSET(GPR2, gpr[2]);
STACK_PT_REGS_OFFSET(GPR3, gpr[3]);
STACK_PT_REGS_OFFSET(GPR4, gpr[4]);
STACK_PT_REGS_OFFSET(GPR5, gpr[5]);
STACK_PT_REGS_OFFSET(GPR6, gpr[6]);
STACK_PT_REGS_OFFSET(GPR7, gpr[7]);
STACK_PT_REGS_OFFSET(GPR8, gpr[8]);
STACK_PT_REGS_OFFSET(GPR9, gpr[9]);
STACK_PT_REGS_OFFSET(GPR10, gpr[10]);
STACK_PT_REGS_OFFSET(GPR11, gpr[11]);
STACK_PT_REGS_OFFSET(GPR12, gpr[12]);
STACK_PT_REGS_OFFSET(GPR13, gpr[13]);
/*
* Note: these symbols include _ because they overlap with special
* register names
*/
STACK_PT_REGS_OFFSET(_NIP, nip);
STACK_PT_REGS_OFFSET(_MSR, msr);
STACK_PT_REGS_OFFSET(_CTR, ctr);
STACK_PT_REGS_OFFSET(_LINK, link);
STACK_PT_REGS_OFFSET(_CCR, ccr);
STACK_PT_REGS_OFFSET(_XER, xer);
STACK_PT_REGS_OFFSET(_DAR, dar);
STACK_PT_REGS_OFFSET(_DEAR, dear);
STACK_PT_REGS_OFFSET(_DSISR, dsisr);
STACK_PT_REGS_OFFSET(_ESR, esr);
STACK_PT_REGS_OFFSET(ORIG_GPR3, orig_gpr3);
STACK_PT_REGS_OFFSET(RESULT, result);
STACK_PT_REGS_OFFSET(_TRAP, trap);
#ifdef CONFIG_PPC64
STACK_PT_REGS_OFFSET(SOFTE, softe);
STACK_PT_REGS_OFFSET(_PPR, ppr);
#endif
#ifdef CONFIG_PPC_PKEY
STACK_PT_REGS_OFFSET(STACK_REGS_AMR, amr);
STACK_PT_REGS_OFFSET(STACK_REGS_IAMR, iamr);
#endif
#if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
STACK_PT_REGS_OFFSET(MAS0, mas0);
/* we overload MMUCR for 44x on MAS0 since they are mutually exclusive */
STACK_PT_REGS_OFFSET(MMUCR, mas0);
STACK_PT_REGS_OFFSET(MAS1, mas1);
STACK_PT_REGS_OFFSET(MAS2, mas2);
STACK_PT_REGS_OFFSET(MAS3, mas3);
STACK_PT_REGS_OFFSET(MAS6, mas6);
STACK_PT_REGS_OFFSET(MAS7, mas7);
STACK_PT_REGS_OFFSET(_SRR0, srr0);
STACK_PT_REGS_OFFSET(_SRR1, srr1);
STACK_PT_REGS_OFFSET(_CSRR0, csrr0);
STACK_PT_REGS_OFFSET(_CSRR1, csrr1);
STACK_PT_REGS_OFFSET(_DSRR0, dsrr0);
STACK_PT_REGS_OFFSET(_DSRR1, dsrr1);
#endif
/* About the CPU features table */
OFFSET(CPU_SPEC_FEATURES, cpu_spec, cpu_features);
OFFSET(CPU_SPEC_SETUP, cpu_spec, cpu_setup);
OFFSET(CPU_SPEC_RESTORE, cpu_spec, cpu_restore);
OFFSET(pbe_address, pbe, address);
OFFSET(pbe_orig_address, pbe, orig_address);
OFFSET(pbe_next, pbe, next);
#ifndef CONFIG_PPC64
DEFINE(TASK_SIZE, TASK_SIZE);
DEFINE(NUM_USER_SEGMENTS, TASK_SIZE>>28);
#endif /* ! CONFIG_PPC64 */
/* datapage offsets for use by vdso */
powerpc/vdso: Switch VDSO to generic C implementation. With the C VDSO, the performance is slightly lower, but it is worth it as it will ease maintenance and evolution, and also brings clocks that are not supported with the ASM VDSO. On an 8xx at 132 MHz, vdsotest with the ASM VDSO: gettimeofday: vdso: 828 nsec/call clock-getres-realtime-coarse: vdso: 391 nsec/call clock-gettime-realtime-coarse: vdso: 614 nsec/call clock-getres-realtime: vdso: 460 nsec/call clock-gettime-realtime: vdso: 876 nsec/call clock-getres-monotonic-coarse: vdso: 399 nsec/call clock-gettime-monotonic-coarse: vdso: 691 nsec/call clock-getres-monotonic: vdso: 460 nsec/call clock-gettime-monotonic: vdso: 1026 nsec/call On an 8xx at 132 MHz, vdsotest with the C VDSO: gettimeofday: vdso: 955 nsec/call clock-getres-realtime-coarse: vdso: 545 nsec/call clock-gettime-realtime-coarse: vdso: 592 nsec/call clock-getres-realtime: vdso: 545 nsec/call clock-gettime-realtime: vdso: 941 nsec/call clock-getres-monotonic-coarse: vdso: 545 nsec/call clock-gettime-monotonic-coarse: vdso: 591 nsec/call clock-getres-monotonic: vdso: 545 nsec/call clock-gettime-monotonic: vdso: 940 nsec/call It is even better for gettime with monotonic clocks. Unsupported clocks with ASM VDSO: clock-gettime-boottime: vdso: 3851 nsec/call clock-gettime-tai: vdso: 3852 nsec/call clock-gettime-monotonic-raw: vdso: 3396 nsec/call Same clocks with C VDSO: clock-gettime-tai: vdso: 941 nsec/call clock-gettime-monotonic-raw: vdso: 1001 nsec/call clock-gettime-monotonic-coarse: vdso: 591 nsec/call On an 8321E at 333 MHz, vdsotest with the ASM VDSO: gettimeofday: vdso: 220 nsec/call clock-getres-realtime-coarse: vdso: 102 nsec/call clock-gettime-realtime-coarse: vdso: 178 nsec/call clock-getres-realtime: vdso: 129 nsec/call clock-gettime-realtime: vdso: 235 nsec/call clock-getres-monotonic-coarse: vdso: 105 nsec/call clock-gettime-monotonic-coarse: vdso: 208 nsec/call clock-getres-monotonic: vdso: 129 nsec/call clock-gettime-monotonic: vdso: 274 nsec/call On an 8321E at 333 MHz, vdsotest with the C VDSO: gettimeofday: vdso: 272 nsec/call clock-getres-realtime-coarse: vdso: 160 nsec/call clock-gettime-realtime-coarse: vdso: 184 nsec/call clock-getres-realtime: vdso: 166 nsec/call clock-gettime-realtime: vdso: 281 nsec/call clock-getres-monotonic-coarse: vdso: 160 nsec/call clock-gettime-monotonic-coarse: vdso: 184 nsec/call clock-getres-monotonic: vdso: 169 nsec/call clock-gettime-monotonic: vdso: 275 nsec/call On a Power9 Nimbus DD2.2 at 3.8GHz, with the ASM VDSO: clock-gettime-monotonic: vdso: 35 nsec/call clock-getres-monotonic: vdso: 16 nsec/call clock-gettime-monotonic-coarse: vdso: 18 nsec/call clock-getres-monotonic-coarse: vdso: 522 nsec/call clock-gettime-monotonic-raw: vdso: 598 nsec/call clock-getres-monotonic-raw: vdso: 520 nsec/call clock-gettime-realtime: vdso: 34 nsec/call clock-getres-realtime: vdso: 16 nsec/call clock-gettime-realtime-coarse: vdso: 18 nsec/call clock-getres-realtime-coarse: vdso: 517 nsec/call getcpu: vdso: 8 nsec/call gettimeofday: vdso: 25 nsec/call And with the C VDSO: clock-gettime-monotonic: vdso: 37 nsec/call clock-getres-monotonic: vdso: 20 nsec/call clock-gettime-monotonic-coarse: vdso: 21 nsec/call clock-getres-monotonic-coarse: vdso: 19 nsec/call clock-gettime-monotonic-raw: vdso: 38 nsec/call clock-getres-monotonic-raw: vdso: 20 nsec/call clock-gettime-realtime: vdso: 37 nsec/call clock-getres-realtime: vdso: 20 nsec/call clock-gettime-realtime-coarse: vdso: 20 nsec/call clock-getres-realtime-coarse: vdso: 19 nsec/call getcpu: vdso: 8 nsec/call gettimeofday: vdso: 28 nsec/call Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201126131006.2431205-8-mpe@ellerman.id.au
2020-11-26 13:10:05 +00:00
OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data);
OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec);
#ifdef CONFIG_PPC64
powerpc/vdso: Switch VDSO to generic C implementation. With the C VDSO, the performance is slightly lower, but it is worth it as it will ease maintenance and evolution, and also brings clocks that are not supported with the ASM VDSO. On an 8xx at 132 MHz, vdsotest with the ASM VDSO: gettimeofday: vdso: 828 nsec/call clock-getres-realtime-coarse: vdso: 391 nsec/call clock-gettime-realtime-coarse: vdso: 614 nsec/call clock-getres-realtime: vdso: 460 nsec/call clock-gettime-realtime: vdso: 876 nsec/call clock-getres-monotonic-coarse: vdso: 399 nsec/call clock-gettime-monotonic-coarse: vdso: 691 nsec/call clock-getres-monotonic: vdso: 460 nsec/call clock-gettime-monotonic: vdso: 1026 nsec/call On an 8xx at 132 MHz, vdsotest with the C VDSO: gettimeofday: vdso: 955 nsec/call clock-getres-realtime-coarse: vdso: 545 nsec/call clock-gettime-realtime-coarse: vdso: 592 nsec/call clock-getres-realtime: vdso: 545 nsec/call clock-gettime-realtime: vdso: 941 nsec/call clock-getres-monotonic-coarse: vdso: 545 nsec/call clock-gettime-monotonic-coarse: vdso: 591 nsec/call clock-getres-monotonic: vdso: 545 nsec/call clock-gettime-monotonic: vdso: 940 nsec/call It is even better for gettime with monotonic clocks. Unsupported clocks with ASM VDSO: clock-gettime-boottime: vdso: 3851 nsec/call clock-gettime-tai: vdso: 3852 nsec/call clock-gettime-monotonic-raw: vdso: 3396 nsec/call Same clocks with C VDSO: clock-gettime-tai: vdso: 941 nsec/call clock-gettime-monotonic-raw: vdso: 1001 nsec/call clock-gettime-monotonic-coarse: vdso: 591 nsec/call On an 8321E at 333 MHz, vdsotest with the ASM VDSO: gettimeofday: vdso: 220 nsec/call clock-getres-realtime-coarse: vdso: 102 nsec/call clock-gettime-realtime-coarse: vdso: 178 nsec/call clock-getres-realtime: vdso: 129 nsec/call clock-gettime-realtime: vdso: 235 nsec/call clock-getres-monotonic-coarse: vdso: 105 nsec/call clock-gettime-monotonic-coarse: vdso: 208 nsec/call clock-getres-monotonic: vdso: 129 nsec/call clock-gettime-monotonic: vdso: 274 nsec/call On an 8321E at 333 MHz, vdsotest with the C VDSO: gettimeofday: vdso: 272 nsec/call clock-getres-realtime-coarse: vdso: 160 nsec/call clock-gettime-realtime-coarse: vdso: 184 nsec/call clock-getres-realtime: vdso: 166 nsec/call clock-gettime-realtime: vdso: 281 nsec/call clock-getres-monotonic-coarse: vdso: 160 nsec/call clock-gettime-monotonic-coarse: vdso: 184 nsec/call clock-getres-monotonic: vdso: 169 nsec/call clock-gettime-monotonic: vdso: 275 nsec/call On a Power9 Nimbus DD2.2 at 3.8GHz, with the ASM VDSO: clock-gettime-monotonic: vdso: 35 nsec/call clock-getres-monotonic: vdso: 16 nsec/call clock-gettime-monotonic-coarse: vdso: 18 nsec/call clock-getres-monotonic-coarse: vdso: 522 nsec/call clock-gettime-monotonic-raw: vdso: 598 nsec/call clock-getres-monotonic-raw: vdso: 520 nsec/call clock-gettime-realtime: vdso: 34 nsec/call clock-getres-realtime: vdso: 16 nsec/call clock-gettime-realtime-coarse: vdso: 18 nsec/call clock-getres-realtime-coarse: vdso: 517 nsec/call getcpu: vdso: 8 nsec/call gettimeofday: vdso: 25 nsec/call And with the C VDSO: clock-gettime-monotonic: vdso: 37 nsec/call clock-getres-monotonic: vdso: 20 nsec/call clock-gettime-monotonic-coarse: vdso: 21 nsec/call clock-getres-monotonic-coarse: vdso: 19 nsec/call clock-gettime-monotonic-raw: vdso: 38 nsec/call clock-getres-monotonic-raw: vdso: 20 nsec/call clock-gettime-realtime: vdso: 37 nsec/call clock-getres-realtime: vdso: 20 nsec/call clock-gettime-realtime-coarse: vdso: 20 nsec/call clock-getres-realtime-coarse: vdso: 19 nsec/call getcpu: vdso: 8 nsec/call gettimeofday: vdso: 28 nsec/call Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201126131006.2431205-8-mpe@ellerman.id.au
2020-11-26 13:10:05 +00:00
OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size);
OFFSET(CFG_DCACHE_BLOCKSZ, vdso_arch_data, dcache_block_size);
OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_arch_data, icache_log_block_size);
OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_arch_data, dcache_log_block_size);
OFFSET(CFG_SYSCALL_MAP64, vdso_arch_data, syscall_map);
OFFSET(CFG_SYSCALL_MAP32, vdso_arch_data, compat_syscall_map);
#else
OFFSET(CFG_SYSCALL_MAP32, vdso_arch_data, syscall_map);
powerpc/vdso: Switch VDSO to generic C implementation. With the C VDSO, the performance is slightly lower, but it is worth it as it will ease maintenance and evolution, and also brings clocks that are not supported with the ASM VDSO. On an 8xx at 132 MHz, vdsotest with the ASM VDSO: gettimeofday: vdso: 828 nsec/call clock-getres-realtime-coarse: vdso: 391 nsec/call clock-gettime-realtime-coarse: vdso: 614 nsec/call clock-getres-realtime: vdso: 460 nsec/call clock-gettime-realtime: vdso: 876 nsec/call clock-getres-monotonic-coarse: vdso: 399 nsec/call clock-gettime-monotonic-coarse: vdso: 691 nsec/call clock-getres-monotonic: vdso: 460 nsec/call clock-gettime-monotonic: vdso: 1026 nsec/call On an 8xx at 132 MHz, vdsotest with the C VDSO: gettimeofday: vdso: 955 nsec/call clock-getres-realtime-coarse: vdso: 545 nsec/call clock-gettime-realtime-coarse: vdso: 592 nsec/call clock-getres-realtime: vdso: 545 nsec/call clock-gettime-realtime: vdso: 941 nsec/call clock-getres-monotonic-coarse: vdso: 545 nsec/call clock-gettime-monotonic-coarse: vdso: 591 nsec/call clock-getres-monotonic: vdso: 545 nsec/call clock-gettime-monotonic: vdso: 940 nsec/call It is even better for gettime with monotonic clocks. Unsupported clocks with ASM VDSO: clock-gettime-boottime: vdso: 3851 nsec/call clock-gettime-tai: vdso: 3852 nsec/call clock-gettime-monotonic-raw: vdso: 3396 nsec/call Same clocks with C VDSO: clock-gettime-tai: vdso: 941 nsec/call clock-gettime-monotonic-raw: vdso: 1001 nsec/call clock-gettime-monotonic-coarse: vdso: 591 nsec/call On an 8321E at 333 MHz, vdsotest with the ASM VDSO: gettimeofday: vdso: 220 nsec/call clock-getres-realtime-coarse: vdso: 102 nsec/call clock-gettime-realtime-coarse: vdso: 178 nsec/call clock-getres-realtime: vdso: 129 nsec/call clock-gettime-realtime: vdso: 235 nsec/call clock-getres-monotonic-coarse: vdso: 105 nsec/call clock-gettime-monotonic-coarse: vdso: 208 nsec/call clock-getres-monotonic: vdso: 129 nsec/call clock-gettime-monotonic: vdso: 274 nsec/call On an 8321E at 333 MHz, vdsotest with the C VDSO: gettimeofday: vdso: 272 nsec/call clock-getres-realtime-coarse: vdso: 160 nsec/call clock-gettime-realtime-coarse: vdso: 184 nsec/call clock-getres-realtime: vdso: 166 nsec/call clock-gettime-realtime: vdso: 281 nsec/call clock-getres-monotonic-coarse: vdso: 160 nsec/call clock-gettime-monotonic-coarse: vdso: 184 nsec/call clock-getres-monotonic: vdso: 169 nsec/call clock-gettime-monotonic: vdso: 275 nsec/call On a Power9 Nimbus DD2.2 at 3.8GHz, with the ASM VDSO: clock-gettime-monotonic: vdso: 35 nsec/call clock-getres-monotonic: vdso: 16 nsec/call clock-gettime-monotonic-coarse: vdso: 18 nsec/call clock-getres-monotonic-coarse: vdso: 522 nsec/call clock-gettime-monotonic-raw: vdso: 598 nsec/call clock-getres-monotonic-raw: vdso: 520 nsec/call clock-gettime-realtime: vdso: 34 nsec/call clock-getres-realtime: vdso: 16 nsec/call clock-gettime-realtime-coarse: vdso: 18 nsec/call clock-getres-realtime-coarse: vdso: 517 nsec/call getcpu: vdso: 8 nsec/call gettimeofday: vdso: 25 nsec/call And with the C VDSO: clock-gettime-monotonic: vdso: 37 nsec/call clock-getres-monotonic: vdso: 20 nsec/call clock-gettime-monotonic-coarse: vdso: 21 nsec/call clock-getres-monotonic-coarse: vdso: 19 nsec/call clock-gettime-monotonic-raw: vdso: 38 nsec/call clock-getres-monotonic-raw: vdso: 20 nsec/call clock-gettime-realtime: vdso: 37 nsec/call clock-getres-realtime: vdso: 20 nsec/call clock-gettime-realtime-coarse: vdso: 20 nsec/call clock-getres-realtime-coarse: vdso: 19 nsec/call getcpu: vdso: 8 nsec/call gettimeofday: vdso: 28 nsec/call Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201126131006.2431205-8-mpe@ellerman.id.au
2020-11-26 13:10:05 +00:00
#endif
#ifdef CONFIG_BUG
DEFINE(BUG_ENTRY_SIZE, sizeof(struct bug_entry));
#endif
#ifdef CONFIG_KVM
OFFSET(VCPU_HOST_STACK, kvm_vcpu, arch.host_stack);
OFFSET(VCPU_HOST_PID, kvm_vcpu, arch.host_pid);
OFFSET(VCPU_GUEST_PID, kvm_vcpu, arch.pid);
OFFSET(VCPU_GPRS, kvm_vcpu, arch.regs.gpr);
OFFSET(VCPU_VRSAVE, kvm_vcpu, arch.vrsave);
OFFSET(VCPU_FPRS, kvm_vcpu, arch.fp.fpr);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
#ifdef CONFIG_ALTIVEC
OFFSET(VCPU_VRS, kvm_vcpu, arch.vr.vr);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
#endif
OFFSET(VCPU_XER, kvm_vcpu, arch.regs.xer);
OFFSET(VCPU_CTR, kvm_vcpu, arch.regs.ctr);
OFFSET(VCPU_LR, kvm_vcpu, arch.regs.link);
#ifdef CONFIG_PPC_BOOK3S
OFFSET(VCPU_TAR, kvm_vcpu, arch.tar);
#endif
OFFSET(VCPU_CR, kvm_vcpu, arch.regs.ccr);
OFFSET(VCPU_PC, kvm_vcpu, arch.regs.nip);
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
OFFSET(VCPU_MSR, kvm_vcpu, arch.shregs.msr);
OFFSET(VCPU_SRR0, kvm_vcpu, arch.shregs.srr0);
OFFSET(VCPU_SRR1, kvm_vcpu, arch.shregs.srr1);
OFFSET(VCPU_SPRG0, kvm_vcpu, arch.shregs.sprg0);
OFFSET(VCPU_SPRG1, kvm_vcpu, arch.shregs.sprg1);
OFFSET(VCPU_SPRG2, kvm_vcpu, arch.shregs.sprg2);
OFFSET(VCPU_SPRG3, kvm_vcpu, arch.shregs.sprg3);
KVM: PPC: Book3S HV: Accumulate timing information for real-mode code This reads the timebase at various points in the real-mode guest entry/exit code and uses that to accumulate total, minimum and maximum time spent in those parts of the code. Currently these times are accumulated per vcpu in 5 parts of the code: * rm_entry - time taken from the start of kvmppc_hv_entry() until just before entering the guest. * rm_intr - time from when we take a hypervisor interrupt in the guest until we either re-enter the guest or decide to exit to the host. This includes time spent handling hcalls in real mode. * rm_exit - time from when we decide to exit the guest until the return from kvmppc_hv_entry(). * guest - time spend in the guest * cede - time spent napping in real mode due to an H_CEDE hcall while other threads in the same vcore are active. These times are exposed in debugfs in a directory per vcpu that contains a file called "timings". This file contains one line for each of the 5 timings above, with the name followed by a colon and 4 numbers, which are the count (number of times the code has been executed), the total time, the minimum time, and the maximum time, all in nanoseconds. The overhead of the extra code amounts to about 30ns for an hcall that is handled in real mode (e.g. H_SET_DABR), which is about 25%. Since production environments may not wish to incur this overhead, the new code is conditional on a new config symbol, CONFIG_KVM_BOOK3S_HV_EXIT_TIMING. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-28 03:21:02 +00:00
#endif
#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
OFFSET(VCPU_TB_RMENTRY, kvm_vcpu, arch.rm_entry);
OFFSET(VCPU_TB_RMINTR, kvm_vcpu, arch.rm_intr);
OFFSET(VCPU_TB_RMEXIT, kvm_vcpu, arch.rm_exit);
OFFSET(VCPU_TB_GUEST, kvm_vcpu, arch.guest_time);
OFFSET(VCPU_TB_CEDE, kvm_vcpu, arch.cede_time);
OFFSET(VCPU_CUR_ACTIVITY, kvm_vcpu, arch.cur_activity);
OFFSET(VCPU_ACTIVITY_START, kvm_vcpu, arch.cur_tb_start);
OFFSET(TAS_SEQCOUNT, kvmhv_tb_accumulator, seqcount);
OFFSET(TAS_TOTAL, kvmhv_tb_accumulator, tb_total);
OFFSET(TAS_MIN, kvmhv_tb_accumulator, tb_min);
OFFSET(TAS_MAX, kvmhv_tb_accumulator, tb_max);
#endif
OFFSET(VCPU_SHARED_SPRG3, kvm_vcpu_arch_shared, sprg3);
OFFSET(VCPU_SHARED_SPRG4, kvm_vcpu_arch_shared, sprg4);
OFFSET(VCPU_SHARED_SPRG5, kvm_vcpu_arch_shared, sprg5);
OFFSET(VCPU_SHARED_SPRG6, kvm_vcpu_arch_shared, sprg6);
OFFSET(VCPU_SHARED_SPRG7, kvm_vcpu_arch_shared, sprg7);
OFFSET(VCPU_SHADOW_PID, kvm_vcpu, arch.shadow_pid);
OFFSET(VCPU_SHADOW_PID1, kvm_vcpu, arch.shadow_pid1);
OFFSET(VCPU_SHARED, kvm_vcpu, arch.shared);
OFFSET(VCPU_SHARED_MSR, kvm_vcpu_arch_shared, msr);
OFFSET(VCPU_SHADOW_MSR, kvm_vcpu, arch.shadow_msr);
#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)
OFFSET(VCPU_SHAREDBE, kvm_vcpu, arch.shared_big_endian);
#endif
OFFSET(VCPU_SHARED_MAS0, kvm_vcpu_arch_shared, mas0);
OFFSET(VCPU_SHARED_MAS1, kvm_vcpu_arch_shared, mas1);
OFFSET(VCPU_SHARED_MAS2, kvm_vcpu_arch_shared, mas2);
OFFSET(VCPU_SHARED_MAS7_3, kvm_vcpu_arch_shared, mas7_3);
OFFSET(VCPU_SHARED_MAS4, kvm_vcpu_arch_shared, mas4);
OFFSET(VCPU_SHARED_MAS6, kvm_vcpu_arch_shared, mas6);
OFFSET(VCPU_KVM, kvm_vcpu, kvm);
OFFSET(KVM_LPID, kvm, arch.lpid);
/* book3s */
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
OFFSET(KVM_TLB_SETS, kvm, arch.tlb_sets);
OFFSET(KVM_SDR1, kvm, arch.sdr1);
OFFSET(KVM_HOST_LPID, kvm, arch.host_lpid);
OFFSET(KVM_HOST_LPCR, kvm, arch.host_lpcr);
OFFSET(KVM_HOST_SDR1, kvm, arch.host_sdr1);
OFFSET(KVM_ENABLED_HCALLS, kvm, arch.enabled_hcalls);
OFFSET(KVM_VRMA_SLB_V, kvm, arch.vrma_slb_v);
OFFSET(KVM_RADIX, kvm, arch.radix);
OFFSET(KVM_SECURE_GUEST, kvm, arch.secure_guest);
OFFSET(VCPU_DSISR, kvm_vcpu, arch.shregs.dsisr);
OFFSET(VCPU_DAR, kvm_vcpu, arch.shregs.dar);
OFFSET(VCPU_VPA, kvm_vcpu, arch.vpa.pinned_addr);
OFFSET(VCPU_VPA_DIRTY, kvm_vcpu, arch.vpa.dirty);
OFFSET(VCPU_HEIR, kvm_vcpu, arch.emul_inst);
OFFSET(VCPU_NESTED, kvm_vcpu, arch.nested);
OFFSET(VCPU_CPU, kvm_vcpu, cpu);
OFFSET(VCPU_THREAD_CPU, kvm_vcpu, arch.thread_cpu);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
#endif
#ifdef CONFIG_PPC_BOOK3S
OFFSET(VCPU_PURR, kvm_vcpu, arch.purr);
OFFSET(VCPU_SPURR, kvm_vcpu, arch.spurr);
OFFSET(VCPU_IC, kvm_vcpu, arch.ic);
OFFSET(VCPU_DSCR, kvm_vcpu, arch.dscr);
OFFSET(VCPU_AMR, kvm_vcpu, arch.amr);
OFFSET(VCPU_UAMOR, kvm_vcpu, arch.uamor);
OFFSET(VCPU_IAMR, kvm_vcpu, arch.iamr);
OFFSET(VCPU_CTRL, kvm_vcpu, arch.ctrl);
OFFSET(VCPU_DABR, kvm_vcpu, arch.dabr);
OFFSET(VCPU_DABRX, kvm_vcpu, arch.dabrx);
OFFSET(VCPU_DAWR0, kvm_vcpu, arch.dawr0);
OFFSET(VCPU_DAWRX0, kvm_vcpu, arch.dawrx0);
OFFSET(VCPU_DAWR1, kvm_vcpu, arch.dawr1);
OFFSET(VCPU_DAWRX1, kvm_vcpu, arch.dawrx1);
OFFSET(VCPU_CIABR, kvm_vcpu, arch.ciabr);
OFFSET(VCPU_HFLAGS, kvm_vcpu, arch.hflags);
OFFSET(VCPU_DEC_EXPIRES, kvm_vcpu, arch.dec_expires);
OFFSET(VCPU_PENDING_EXC, kvm_vcpu, arch.pending_exceptions);
OFFSET(VCPU_CEDED, kvm_vcpu, arch.ceded);
OFFSET(VCPU_PRODDED, kvm_vcpu, arch.prodded);
OFFSET(VCPU_IRQ_PENDING, kvm_vcpu, arch.irq_pending);
KVM: PPC: Book3S HV: Virtualize doorbell facility on POWER9 On POWER9, we no longer have the restriction that we had on POWER8 where all threads in a core have to be in the same partition, so the CPU threads are now independent. However, we still want to be able to run guests with a virtual SMT topology, if only to allow migration of guests from POWER8 systems to POWER9. A guest that has a virtual SMT mode greater than 1 will expect to be able to use the doorbell facility; it will expect the msgsndp and msgclrp instructions to work appropriately and to be able to read sensible values from the TIR (thread identification register) and DPDES (directed privileged doorbell exception status) special-purpose registers. However, since each CPU thread is a separate sub-processor in POWER9, these instructions and registers can only be used within a single CPU thread. In order for these instructions to appear to act correctly according to the guest's virtual SMT mode, we have to trap and emulate them. We cause them to trap by clearing the HFSCR_MSGP bit in the HFSCR register. The emulation is triggered by the hypervisor facility unavailable interrupt that occurs when the guest uses them. To cause a doorbell interrupt to occur within the guest, we set the DPDES register to 1. If the guest has interrupts enabled, the CPU will generate a doorbell interrupt and clear the DPDES register in hardware. The DPDES hardware register for the guest is saved in the vcpu->arch.vcore->dpdes field. Since this gets written by the guest exit code, other VCPUs wishing to cause a doorbell interrupt don't write that field directly, but instead set a vcpu->arch.doorbell_request flag. This is consumed and set to 0 by the guest entry code, which then sets DPDES to 1. Emulating reads of the DPDES register is somewhat involved, because it requires reading the doorbell pending interrupt status of all of the VCPU threads in the virtual core, and if any of those VCPUs are running, their doorbell status is only up-to-date in the hardware DPDES registers of the CPUs where they are running. In order to get a reasonable approximation of the current doorbell status, we send those CPUs an IPI, causing an exit from the guest which will update the vcpu->arch.vcore->dpdes field. We then use that value in constructing the emulated DPDES register value. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-05-16 06:41:20 +00:00
OFFSET(VCPU_DBELL_REQ, kvm_vcpu, arch.doorbell_request);
OFFSET(VCPU_MMCR, kvm_vcpu, arch.mmcr);
OFFSET(VCPU_MMCRA, kvm_vcpu, arch.mmcra);
OFFSET(VCPU_MMCRS, kvm_vcpu, arch.mmcrs);
OFFSET(VCPU_PMC, kvm_vcpu, arch.pmc);
OFFSET(VCPU_SIAR, kvm_vcpu, arch.siar);
OFFSET(VCPU_SDAR, kvm_vcpu, arch.sdar);
OFFSET(VCPU_SIER, kvm_vcpu, arch.sier);
OFFSET(VCPU_SLB, kvm_vcpu, arch.slb);
OFFSET(VCPU_SLB_MAX, kvm_vcpu, arch.slb_max);
OFFSET(VCPU_SLB_NR, kvm_vcpu, arch.slb_nr);
OFFSET(VCPU_FAULT_DSISR, kvm_vcpu, arch.fault_dsisr);
OFFSET(VCPU_FAULT_DAR, kvm_vcpu, arch.fault_dar);
OFFSET(VCPU_INTR_MSR, kvm_vcpu, arch.intr_msr);
OFFSET(VCPU_LAST_INST, kvm_vcpu, arch.last_inst);
OFFSET(VCPU_TRAP, kvm_vcpu, arch.trap);
OFFSET(VCPU_CFAR, kvm_vcpu, arch.cfar);
OFFSET(VCPU_PPR, kvm_vcpu, arch.ppr);
OFFSET(VCPU_FSCR, kvm_vcpu, arch.fscr);
OFFSET(VCPU_PSPB, kvm_vcpu, arch.pspb);
OFFSET(VCPU_EBBHR, kvm_vcpu, arch.ebbhr);
OFFSET(VCPU_EBBRR, kvm_vcpu, arch.ebbrr);
OFFSET(VCPU_BESCR, kvm_vcpu, arch.bescr);
OFFSET(VCPU_CSIGR, kvm_vcpu, arch.csigr);
OFFSET(VCPU_TACR, kvm_vcpu, arch.tacr);
OFFSET(VCPU_TCSCR, kvm_vcpu, arch.tcscr);
OFFSET(VCPU_ACOP, kvm_vcpu, arch.acop);
OFFSET(VCPU_WORT, kvm_vcpu, arch.wort);
OFFSET(VCPU_TID, kvm_vcpu, arch.tid);
OFFSET(VCPU_PSSCR, kvm_vcpu, arch.psscr);
OFFSET(VCPU_HFSCR, kvm_vcpu, arch.hfscr);
OFFSET(VCORE_ENTRY_EXIT, kvmppc_vcore, entry_exit_map);
OFFSET(VCORE_IN_GUEST, kvmppc_vcore, in_guest);
OFFSET(VCORE_NAPPING_THREADS, kvmppc_vcore, napping_threads);
OFFSET(VCORE_KVM, kvmppc_vcore, kvm);
OFFSET(VCORE_TB_OFFSET, kvmppc_vcore, tb_offset);
KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry Currently, the HV KVM guest entry/exit code adds the timebase offset from the vcore struct to the timebase on guest entry, and subtracts it on guest exit. Which is fine, except that it is possible for userspace to change the offset using the SET_ONE_REG interface while the vcore is running, as there is only one timebase offset per vcore but potentially multiple VCPUs in the vcore. If that were to happen, KVM would subtract a different offset on guest exit from that which it had added on guest entry, leading to the timebase being out of sync between cores in the host, which then leads to bad things happening such as hangs and spurious watchdog timeouts. To fix this, we add a new field 'tb_offset_applied' to the vcore struct which stores the offset that is currently applied to the timebase. This value is set from the vcore tb_offset field on guest entry, and is what is subtracted from the timebase on guest exit. Since it is zero when the timebase offset is not applied, we can simplify the logic in kvmhv_start_timing and kvmhv_accumulate_time. In addition, we had secondary threads reading the timebase while running concurrently with code on the primary thread which would eventually add or subtract the timebase offset from the timebase. This occurred while saving or restoring the DEC register value on the secondary threads. Although no specific incorrect behaviour has been observed, this is a race which should be fixed. To fix it, we move the DEC saving code to just before we call kvmhv_commence_exit, and the DEC restoring code to after the point where we have waited for the primary thread to switch the MMU context and add the timebase offset. That way we are sure that the timebase contains the guest timebase value in both cases. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-04-20 12:51:11 +00:00
OFFSET(VCORE_TB_OFFSET_APPL, kvmppc_vcore, tb_offset_applied);
OFFSET(VCORE_LPCR, kvmppc_vcore, lpcr);
OFFSET(VCORE_PCR, kvmppc_vcore, pcr);
OFFSET(VCORE_DPDES, kvmppc_vcore, dpdes);
OFFSET(VCORE_VTB, kvmppc_vcore, vtb);
OFFSET(VCPU_SLB_E, kvmppc_slb, orige);
OFFSET(VCPU_SLB_V, kvmppc_slb, origv);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
DEFINE(VCPU_SLB_SIZE, sizeof(struct kvmppc_slb));
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
OFFSET(VCPU_TFHAR, kvm_vcpu, arch.tfhar);
OFFSET(VCPU_TFIAR, kvm_vcpu, arch.tfiar);
OFFSET(VCPU_TEXASR, kvm_vcpu, arch.texasr);
KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9 POWER9 has hardware bugs relating to transactional memory and thread reconfiguration (changes to hardware SMT mode). Specifically, the core does not have enough storage to store a complete checkpoint of all the architected state for all four threads. The DD2.2 version of POWER9 includes hardware modifications designed to allow hypervisor software to implement workarounds for these problems. This patch implements those workarounds in KVM code so that KVM guests see a full, working transactional memory implementation. The problems center around the use of TM suspended state, where the CPU has a checkpointed state but execution is not transactional. The workaround is to implement a "fake suspend" state, which looks to the guest like suspended state but the CPU does not store a checkpoint. In this state, any instruction that would cause a transition to transactional state (rfid, rfebb, mtmsrd, tresume) or would use the checkpointed state (treclaim) causes a "soft patch" interrupt (vector 0x1500) to the hypervisor so that it can be emulated. The trechkpt instruction also causes a soft patch interrupt. On POWER9 DD2.2, we avoid returning to the guest in any state which would require a checkpoint to be present. The trechkpt in the guest entry path which would normally create that checkpoint is replaced by either a transition to fake suspend state, if the guest is in suspend state, or a rollback to the pre-transactional state if the guest is in transactional state. Fake suspend state is indicated by a flag in the PACA plus a new bit in the PSSCR. The new PSSCR bit is write-only and reads back as 0. On exit from the guest, if the guest is in fake suspend state, we still do the treclaim instruction as we would in real suspend state, in order to get into non-transactional state, but we do not save the resulting register state since there was no checkpoint. Emulation of the instructions that cause a softpatch interrupt is handled in two paths. If the guest is in real suspend mode, we call kvmhv_p9_tm_emulation_early() to handle the cases where the guest is transitioning to transactional state. This is called before we do the treclaim in the guest exit path; because we haven't done treclaim, we can get back to the guest with the transaction still active. If the instruction is a case that kvmhv_p9_tm_emulation_early() doesn't handle, or if the guest is in fake suspend state, then we proceed to do the complete guest exit path and subsequently call kvmhv_p9_tm_emulation() in host context with the MMU on. This handles all the cases including the cases that generate program interrupts (illegal instruction or TM Bad Thing) and facility unavailable interrupts. The emulation is reasonably straightforward and is mostly concerned with checking for exception conditions and updating the state of registers such as MSR and CR0. The treclaim emulation takes care to ensure that the TEXASR register gets updated as if it were the guest treclaim instruction that had done failure recording, not the treclaim done in hypervisor state in the guest exit path. With this, the KVM_CAP_PPC_HTM capability returns true (1) even if transactional memory is not available to host userspace. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-21 10:32:01 +00:00
OFFSET(VCPU_ORIG_TEXASR, kvm_vcpu, arch.orig_texasr);
OFFSET(VCPU_GPR_TM, kvm_vcpu, arch.gpr_tm);
OFFSET(VCPU_FPRS_TM, kvm_vcpu, arch.fp_tm.fpr);
OFFSET(VCPU_VRS_TM, kvm_vcpu, arch.vr_tm.vr);
OFFSET(VCPU_VRSAVE_TM, kvm_vcpu, arch.vrsave_tm);
OFFSET(VCPU_CR_TM, kvm_vcpu, arch.cr_tm);
OFFSET(VCPU_XER_TM, kvm_vcpu, arch.xer_tm);
OFFSET(VCPU_LR_TM, kvm_vcpu, arch.lr_tm);
OFFSET(VCPU_CTR_TM, kvm_vcpu, arch.ctr_tm);
OFFSET(VCPU_AMR_TM, kvm_vcpu, arch.amr_tm);
OFFSET(VCPU_PPR_TM, kvm_vcpu, arch.ppr_tm);
OFFSET(VCPU_DSCR_TM, kvm_vcpu, arch.dscr_tm);
OFFSET(VCPU_TAR_TM, kvm_vcpu, arch.tar_tm);
#endif
#ifdef CONFIG_PPC_BOOK3S_64
#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
OFFSET(PACA_SVCPU, paca_struct, shadow_vcpu);
# define SVCPU_FIELD(x, f) DEFINE(x, offsetof(struct paca_struct, shadow_vcpu.f))
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
#else
# define SVCPU_FIELD(x, f)
#endif
# define HSTATE_FIELD(x, f) DEFINE(x, offsetof(struct paca_struct, kvm_hstate.f))
#else /* 32-bit */
# define SVCPU_FIELD(x, f) DEFINE(x, offsetof(struct kvmppc_book3s_shadow_vcpu, f))
# define HSTATE_FIELD(x, f) DEFINE(x, offsetof(struct kvmppc_book3s_shadow_vcpu, hstate.f))
#endif
SVCPU_FIELD(SVCPU_CR, cr);
SVCPU_FIELD(SVCPU_XER, xer);
SVCPU_FIELD(SVCPU_CTR, ctr);
SVCPU_FIELD(SVCPU_LR, lr);
SVCPU_FIELD(SVCPU_PC, pc);
SVCPU_FIELD(SVCPU_R0, gpr[0]);
SVCPU_FIELD(SVCPU_R1, gpr[1]);
SVCPU_FIELD(SVCPU_R2, gpr[2]);
SVCPU_FIELD(SVCPU_R3, gpr[3]);
SVCPU_FIELD(SVCPU_R4, gpr[4]);
SVCPU_FIELD(SVCPU_R5, gpr[5]);
SVCPU_FIELD(SVCPU_R6, gpr[6]);
SVCPU_FIELD(SVCPU_R7, gpr[7]);
SVCPU_FIELD(SVCPU_R8, gpr[8]);
SVCPU_FIELD(SVCPU_R9, gpr[9]);
SVCPU_FIELD(SVCPU_R10, gpr[10]);
SVCPU_FIELD(SVCPU_R11, gpr[11]);
SVCPU_FIELD(SVCPU_R12, gpr[12]);
SVCPU_FIELD(SVCPU_R13, gpr[13]);
SVCPU_FIELD(SVCPU_FAULT_DSISR, fault_dsisr);
SVCPU_FIELD(SVCPU_FAULT_DAR, fault_dar);
SVCPU_FIELD(SVCPU_LAST_INST, last_inst);
SVCPU_FIELD(SVCPU_SHADOW_SRR1, shadow_srr1);
#ifdef CONFIG_PPC_BOOK3S_32
SVCPU_FIELD(SVCPU_SR, sr);
#endif
#ifdef CONFIG_PPC64
SVCPU_FIELD(SVCPU_SLB, slb);
SVCPU_FIELD(SVCPU_SLB_MAX, slb_max);
SVCPU_FIELD(SVCPU_SHADOW_FSCR, shadow_fscr);
#endif
HSTATE_FIELD(HSTATE_HOST_R1, host_r1);
HSTATE_FIELD(HSTATE_HOST_R2, host_r2);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
HSTATE_FIELD(HSTATE_HOST_MSR, host_msr);
HSTATE_FIELD(HSTATE_VMHANDLER, vmhandler);
HSTATE_FIELD(HSTATE_SCRATCH0, scratch0);
HSTATE_FIELD(HSTATE_SCRATCH1, scratch1);
HSTATE_FIELD(HSTATE_SCRATCH2, scratch2);
HSTATE_FIELD(HSTATE_IN_GUEST, in_guest);
KVM: PPC: book3s_pr: Simplify transitions between virtual and real mode This simplifies the way that the book3s_pr makes the transition to real mode when entering the guest. We now call kvmppc_entry_trampoline (renamed from kvmppc_rmcall) in the base kernel using a normal function call instead of doing an indirect call through a pointer in the vcpu. If kvm is a module, the module loader takes care of generating a trampoline as it does for other calls to functions outside the module. kvmppc_entry_trampoline then disables interrupts and jumps to kvmppc_handler_trampoline_enter in real mode using an rfi[d]. That then uses the link register as the address to return to (potentially in module space) when the guest exits. This also simplifies the way that we call the Linux interrupt handler when we exit the guest due to an external, decrementer or performance monitor interrupt. Instead of turning on the MMU, then deciding that we need to call the Linux handler and turning the MMU back off again, we now go straight to the handler at the point where we would turn the MMU on. The handler will then return to the virtual-mode code (potentially in the module). Along the way, this moves the setting and clearing of the HID5 DCBZ32 bit into real-mode interrupts-off code, and also makes sure that we clear the MSR[RI] bit before loading values into SRR0/1. The net result is that we no longer need any code addresses to be stored in vcpu->arch. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-23 07:41:44 +00:00
HSTATE_FIELD(HSTATE_RESTORE_HID5, restore_hid5);
KVM: PPC: Implement H_CEDE hcall for book3s_hv in real-mode code With a KVM guest operating in SMT4 mode (i.e. 4 hardware threads per core), whenever a CPU goes idle, we have to pull all the other hardware threads in the core out of the guest, because the H_CEDE hcall is handled in the kernel. This is inefficient. This adds code to book3s_hv_rmhandlers.S to handle the H_CEDE hcall in real mode. When a guest vcpu does an H_CEDE hcall, we now only exit to the kernel if all the other vcpus in the same core are also idle. Otherwise we mark this vcpu as napping, save state that could be lost in nap mode (mainly GPRs and FPRs), and execute the nap instruction. When the thread wakes up, because of a decrementer or external interrupt, we come back in at kvm_start_guest (from the system reset interrupt vector), find the `napping' flag set in the paca, and go to the resume path. This has some other ramifications. First, when starting a core, we now start all the threads, both those that are immediately runnable and those that are idle. This is so that we don't have to pull all the threads out of the guest when an idle thread gets a decrementer interrupt and wants to start running. In fact the idle threads will all start with the H_CEDE hcall returning; being idle they will just do another H_CEDE immediately and go to nap mode. This required some changes to kvmppc_run_core() and kvmppc_run_vcpu(). These functions have been restructured to make them simpler and clearer. We introduce a level of indirection in the wait queue that gets woken when external and decrementer interrupts get generated for a vcpu, so that we can have the 4 vcpus in a vcore using the same wait queue. We need this because the 4 vcpus are being handled by one thread. Secondly, when we need to exit from the guest to the kernel, we now have to generate an IPI for any napping threads, because an HDEC interrupt doesn't wake up a napping thread. Thirdly, we now need to be able to handle virtual external interrupts and decrementer interrupts becoming pending while a thread is napping, and deliver those interrupts to the guest when the thread wakes. This is done in kvmppc_cede_reentry, just before fast_guest_return. Finally, since we are not using the generic kvm_vcpu_block for book3s_hv, and hence not calling kvm_arch_vcpu_runnable, we can remove the #ifdef from kvm_arch_vcpu_runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-23 07:42:46 +00:00
HSTATE_FIELD(HSTATE_NAPPING, napping);
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
HSTATE_FIELD(HSTATE_HWTHREAD_REQ, hwthread_req);
HSTATE_FIELD(HSTATE_HWTHREAD_STATE, hwthread_state);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
HSTATE_FIELD(HSTATE_KVM_VCPU, kvm_vcpu);
KVM: PPC: Allow book3s_hv guests to use SMT processor modes This lifts the restriction that book3s_hv guests can only run one hardware thread per core, and allows them to use up to 4 threads per core on POWER7. The host still has to run single-threaded. This capability is advertised to qemu through a new KVM_CAP_PPC_SMT capability. The return value of the ioctl querying this capability is the number of vcpus per virtual CPU core (vcore), currently 4. To use this, the host kernel should be booted with all threads active, and then all the secondary threads should be offlined. This will put the secondary threads into nap mode. KVM will then wake them from nap mode and use them for running guest code (while they are still offline). To wake the secondary threads, we send them an IPI using a new xics_wake_cpu() function, implemented in arch/powerpc/sysdev/xics/icp-native.c. In other words, at this stage we assume that the platform has a XICS interrupt controller and we are using icp-native.c to drive it. Since the woken thread will need to acknowledge and clear the IPI, we also export the base physical address of the XICS registers using kvmppc_set_xics_phys() for use in the low-level KVM book3s code. When a vcpu is created, it is assigned to a virtual CPU core. The vcore number is obtained by dividing the vcpu number by the number of threads per core in the host. This number is exported to userspace via the KVM_CAP_PPC_SMT capability. If qemu wishes to run the guest in single-threaded mode, it should make all vcpu numbers be multiples of the number of threads per core. We distinguish three states of a vcpu: runnable (i.e., ready to execute the guest), blocked (that is, idle), and busy in host. We currently implement a policy that the vcore can run only when all its threads are runnable or blocked. This way, if a vcpu needs to execute elsewhere in the kernel or in qemu, it can do so without being starved of CPU by the other vcpus. When a vcore starts to run, it executes in the context of one of the vcpu threads. The other vcpu threads all go to sleep and stay asleep until something happens requiring the vcpu thread to return to qemu, or to wake up to run the vcore (this can happen when another vcpu thread goes from busy in host state to blocked). It can happen that a vcpu goes from blocked to runnable state (e.g. because of an interrupt), and the vcore it belongs to is already running. In that case it can start to run immediately as long as the none of the vcpus in the vcore have started to exit the guest. We send the next free thread in the vcore an IPI to get it to start to execute the guest. It synchronizes with the other threads via the vcore->entry_exit_count field to make sure that it doesn't go into the guest if the other vcpus are exiting by the time that it is ready to actually enter the guest. Note that there is no fixed relationship between the hardware thread number and the vcpu number. Hardware threads are assigned to vcpus as they become runnable, so we will always use the lower-numbered hardware threads in preference to higher-numbered threads if not all the vcpus in the vcore are runnable, regardless of which vcpus are runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:23:08 +00:00
HSTATE_FIELD(HSTATE_KVM_VCORE, kvm_vcore);
HSTATE_FIELD(HSTATE_XIVE_TIMA_PHYS, xive_tima_phys);
HSTATE_FIELD(HSTATE_XIVE_TIMA_VIRT, xive_tima_virt);
HSTATE_FIELD(HSTATE_HOST_IPI, host_ipi);
KVM: PPC: Book3S HV: Align physical and virtual CPU thread numbers On a threaded processor such as POWER7, we group VCPUs into virtual cores and arrange that the VCPUs in a virtual core run on the same physical core. Currently we don't enforce any correspondence between virtual thread numbers within a virtual core and physical thread numbers. Physical threads are allocated starting at 0 on a first-come first-served basis to runnable virtual threads (VCPUs). POWER8 implements a new "msgsndp" instruction which guest kernels can use to interrupt other threads in the same core or sub-core. Since the instruction takes the destination physical thread ID as a parameter, it becomes necessary to align the physical thread IDs with the virtual thread IDs, that is, to make sure virtual thread N within a virtual core always runs on physical thread N. This means that it's possible that thread 0, which is where we call __kvmppc_vcore_entry, may end up running some other vcpu than the one whose task called kvmppc_run_core(), or it may end up running no vcpu at all, if for example thread 0 of the virtual core is currently executing in userspace. However, we do need thread 0 to be responsible for switching the MMU -- a previous version of this patch that had other threads switching the MMU was found to be responsible for occasional memory corruption and machine check interrupts in the guest on POWER7 machines. To accommodate this, we no longer pass the vcpu pointer to __kvmppc_vcore_entry, but instead let the assembly code load it from the PACA. Since the assembly code will need to know the kvm pointer and the thread ID for threads which don't have a vcpu, we move the thread ID into the PACA and we add a kvm pointer to the virtual core structure. In the case where thread 0 has no vcpu to run, it still calls into kvmppc_hv_entry in order to do the MMU switch, and then naps until either its vcpu is ready to run in the guest, or some other thread needs to exit the guest. In the latter case, thread 0 jumps to the code that switches the MMU back to the host. This control flow means that now we switch the MMU before loading any guest vcpu state. Similarly, on guest exit we now save all the guest vcpu state before switching the MMU back to the host. This has required substantial code movement, making the diff rather large. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-01-08 10:25:20 +00:00
HSTATE_FIELD(HSTATE_PTID, ptid);
KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9 POWER9 has hardware bugs relating to transactional memory and thread reconfiguration (changes to hardware SMT mode). Specifically, the core does not have enough storage to store a complete checkpoint of all the architected state for all four threads. The DD2.2 version of POWER9 includes hardware modifications designed to allow hypervisor software to implement workarounds for these problems. This patch implements those workarounds in KVM code so that KVM guests see a full, working transactional memory implementation. The problems center around the use of TM suspended state, where the CPU has a checkpointed state but execution is not transactional. The workaround is to implement a "fake suspend" state, which looks to the guest like suspended state but the CPU does not store a checkpoint. In this state, any instruction that would cause a transition to transactional state (rfid, rfebb, mtmsrd, tresume) or would use the checkpointed state (treclaim) causes a "soft patch" interrupt (vector 0x1500) to the hypervisor so that it can be emulated. The trechkpt instruction also causes a soft patch interrupt. On POWER9 DD2.2, we avoid returning to the guest in any state which would require a checkpoint to be present. The trechkpt in the guest entry path which would normally create that checkpoint is replaced by either a transition to fake suspend state, if the guest is in suspend state, or a rollback to the pre-transactional state if the guest is in transactional state. Fake suspend state is indicated by a flag in the PACA plus a new bit in the PSSCR. The new PSSCR bit is write-only and reads back as 0. On exit from the guest, if the guest is in fake suspend state, we still do the treclaim instruction as we would in real suspend state, in order to get into non-transactional state, but we do not save the resulting register state since there was no checkpoint. Emulation of the instructions that cause a softpatch interrupt is handled in two paths. If the guest is in real suspend mode, we call kvmhv_p9_tm_emulation_early() to handle the cases where the guest is transitioning to transactional state. This is called before we do the treclaim in the guest exit path; because we haven't done treclaim, we can get back to the guest with the transaction still active. If the instruction is a case that kvmhv_p9_tm_emulation_early() doesn't handle, or if the guest is in fake suspend state, then we proceed to do the complete guest exit path and subsequently call kvmhv_p9_tm_emulation() in host context with the MMU on. This handles all the cases including the cases that generate program interrupts (illegal instruction or TM Bad Thing) and facility unavailable interrupts. The emulation is reasonably straightforward and is mostly concerned with checking for exception conditions and updating the state of registers such as MSR and CR0. The treclaim emulation takes care to ensure that the TEXASR register gets updated as if it were the guest treclaim instruction that had done failure recording, not the treclaim done in hypervisor state in the guest exit path. With this, the KVM_CAP_PPC_HTM capability returns true (1) even if transactional memory is not available to host userspace. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-21 10:32:01 +00:00
HSTATE_FIELD(HSTATE_FAKE_SUSPEND, fake_suspend);
HSTATE_FIELD(HSTATE_MMCR0, host_mmcr[0]);
HSTATE_FIELD(HSTATE_MMCR1, host_mmcr[1]);
HSTATE_FIELD(HSTATE_MMCRA, host_mmcr[2]);
HSTATE_FIELD(HSTATE_SIAR, host_mmcr[3]);
HSTATE_FIELD(HSTATE_SDAR, host_mmcr[4]);
HSTATE_FIELD(HSTATE_MMCR2, host_mmcr[5]);
HSTATE_FIELD(HSTATE_SIER, host_mmcr[6]);
HSTATE_FIELD(HSTATE_MMCR3, host_mmcr[7]);
HSTATE_FIELD(HSTATE_SIER2, host_mmcr[8]);
HSTATE_FIELD(HSTATE_SIER3, host_mmcr[9]);
HSTATE_FIELD(HSTATE_PMC1, host_pmc[0]);
HSTATE_FIELD(HSTATE_PMC2, host_pmc[1]);
HSTATE_FIELD(HSTATE_PMC3, host_pmc[2]);
HSTATE_FIELD(HSTATE_PMC4, host_pmc[3]);
HSTATE_FIELD(HSTATE_PMC5, host_pmc[4]);
HSTATE_FIELD(HSTATE_PMC6, host_pmc[5]);
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
HSTATE_FIELD(HSTATE_PURR, host_purr);
HSTATE_FIELD(HSTATE_SPURR, host_spurr);
HSTATE_FIELD(HSTATE_DSCR, host_dscr);
HSTATE_FIELD(HSTATE_DABR, dabr);
HSTATE_FIELD(HSTATE_DECEXP, dec_expires);
KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8 This builds on the ability to run more than one vcore on a physical core by using the micro-threading (split-core) modes of the POWER8 chip. Previously, only vcores from the same VM could be run together, and (on POWER8) only if they had just one thread per core. With the ability to split the core on guest entry and unsplit it on guest exit, we can run up to 8 vcpu threads from up to 4 different VMs, and we can run multiple vcores with 2 or 4 vcpus per vcore. Dynamic micro-threading is only available if the static configuration of the cores is whole-core mode (unsplit), and only on POWER8. To manage this, we introduce a new kvm_split_mode struct which is shared across all of the subcores in the core, with a pointer in the paca on each thread. In addition we extend the core_info struct to have information on each subcore. When deciding whether to add a vcore to the set already on the core, we now have two possibilities: (a) piggyback the vcore onto an existing subcore, or (b) start a new subcore. Currently, when any vcpu needs to exit the guest and switch to host virtual mode, we interrupt all the threads in all subcores and switch the core back to whole-core mode. It may be possible in future to allow some of the subcores to keep executing in the guest while subcore 0 switches to the host, but that is not implemented in this patch. This adds a module parameter called dynamic_mt_modes which controls which micro-threading (split-core) modes the code will consider, as a bitmap. In other words, if it is 0, no micro-threading mode is considered; if it is 2, only 2-way micro-threading is considered; if it is 4, only 4-way, and if it is 6, both 2-way and 4-way micro-threading mode will be considered. The default is 6. With this, we now have secondary threads which are the primary thread for their subcore and therefore need to do the MMU switch. These threads will need to be started even if they have no vcpu to run, so we use the vcore pointer in the PACA rather than the vcpu pointer to trigger them. It is now possible for thread 0 to find that an exit has been requested before it gets to switch the subcore state to the guest. In that case we haven't added the guest's timebase offset to the timebase, so we need to be careful not to subtract the offset in the guest exit path. In fact we just skip the whole path that switches back to host context, since we haven't switched to the guest context. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-07-02 10:38:16 +00:00
HSTATE_FIELD(HSTATE_SPLIT_MODE, kvm_split_mode);
KVM: PPC: Implement H_CEDE hcall for book3s_hv in real-mode code With a KVM guest operating in SMT4 mode (i.e. 4 hardware threads per core), whenever a CPU goes idle, we have to pull all the other hardware threads in the core out of the guest, because the H_CEDE hcall is handled in the kernel. This is inefficient. This adds code to book3s_hv_rmhandlers.S to handle the H_CEDE hcall in real mode. When a guest vcpu does an H_CEDE hcall, we now only exit to the kernel if all the other vcpus in the same core are also idle. Otherwise we mark this vcpu as napping, save state that could be lost in nap mode (mainly GPRs and FPRs), and execute the nap instruction. When the thread wakes up, because of a decrementer or external interrupt, we come back in at kvm_start_guest (from the system reset interrupt vector), find the `napping' flag set in the paca, and go to the resume path. This has some other ramifications. First, when starting a core, we now start all the threads, both those that are immediately runnable and those that are idle. This is so that we don't have to pull all the threads out of the guest when an idle thread gets a decrementer interrupt and wants to start running. In fact the idle threads will all start with the H_CEDE hcall returning; being idle they will just do another H_CEDE immediately and go to nap mode. This required some changes to kvmppc_run_core() and kvmppc_run_vcpu(). These functions have been restructured to make them simpler and clearer. We introduce a level of indirection in the wait queue that gets woken when external and decrementer interrupts get generated for a vcpu, so that we can have the 4 vcpus in a vcore using the same wait queue. We need this because the 4 vcpus are being handled by one thread. Secondly, when we need to exit from the guest to the kernel, we now have to generate an IPI for any napping threads, because an HDEC interrupt doesn't wake up a napping thread. Thirdly, we now need to be able to handle virtual external interrupts and decrementer interrupts becoming pending while a thread is napping, and deliver those interrupts to the guest when the thread wakes. This is done in kvmppc_cede_reentry, just before fast_guest_return. Finally, since we are not using the generic kvm_vcpu_block for book3s_hv, and hence not calling kvm_arch_vcpu_runnable, we can remove the #ifdef from kvm_arch_vcpu_runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-23 07:42:46 +00:00
DEFINE(IPI_PRIORITY, IPI_PRIORITY);
OFFSET(KVM_SPLIT_RPR, kvm_split_mode, rpr);
OFFSET(KVM_SPLIT_PMMAR, kvm_split_mode, pmmar);
OFFSET(KVM_SPLIT_LDBAR, kvm_split_mode, ldbar);
OFFSET(KVM_SPLIT_DO_NAP, kvm_split_mode, do_nap);
OFFSET(KVM_SPLIT_NAPPED, kvm_split_mode, napped);
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 00:21:34 +00:00
#ifdef CONFIG_PPC_BOOK3S_64
HSTATE_FIELD(HSTATE_CFAR, cfar);
HSTATE_FIELD(HSTATE_PPR, ppr);
HSTATE_FIELD(HSTATE_HOST_FSCR, host_fscr);
#endif /* CONFIG_PPC_BOOK3S_64 */
#else /* CONFIG_PPC_BOOK3S */
OFFSET(VCPU_CR, kvm_vcpu, arch.regs.ccr);
OFFSET(VCPU_XER, kvm_vcpu, arch.regs.xer);
OFFSET(VCPU_LR, kvm_vcpu, arch.regs.link);
OFFSET(VCPU_CTR, kvm_vcpu, arch.regs.ctr);
OFFSET(VCPU_PC, kvm_vcpu, arch.regs.nip);
OFFSET(VCPU_SPRG9, kvm_vcpu, arch.sprg9);
OFFSET(VCPU_LAST_INST, kvm_vcpu, arch.last_inst);
OFFSET(VCPU_FAULT_DEAR, kvm_vcpu, arch.fault_dear);
OFFSET(VCPU_FAULT_ESR, kvm_vcpu, arch.fault_esr);
OFFSET(VCPU_CRIT_SAVE, kvm_vcpu, arch.crit_save);
#endif /* CONFIG_PPC_BOOK3S */
#endif /* CONFIG_KVM */
#ifdef CONFIG_KVM_GUEST
OFFSET(KVM_MAGIC_SCRATCH1, kvm_vcpu_arch_shared, scratch1);
OFFSET(KVM_MAGIC_SCRATCH2, kvm_vcpu_arch_shared, scratch2);
OFFSET(KVM_MAGIC_SCRATCH3, kvm_vcpu_arch_shared, scratch3);
OFFSET(KVM_MAGIC_INT, kvm_vcpu_arch_shared, int_pending);
OFFSET(KVM_MAGIC_MSR, kvm_vcpu_arch_shared, msr);
OFFSET(KVM_MAGIC_CRITICAL, kvm_vcpu_arch_shared, critical);
OFFSET(KVM_MAGIC_SR, kvm_vcpu_arch_shared, sr);
#endif
#ifdef CONFIG_44x
DEFINE(PGD_T_LOG2, PGD_T_LOG2);
DEFINE(PTE_T_LOG2, PTE_T_LOG2);
#endif
#ifdef CONFIG_PPC_FSL_BOOK3E
DEFINE(TLBCAM_SIZE, sizeof(struct tlbcam));
OFFSET(TLBCAM_MAS0, tlbcam, MAS0);
OFFSET(TLBCAM_MAS1, tlbcam, MAS1);
OFFSET(TLBCAM_MAS2, tlbcam, MAS2);
OFFSET(TLBCAM_MAS3, tlbcam, MAS3);
OFFSET(TLBCAM_MAS7, tlbcam, MAS7);
#endif
#if defined(CONFIG_KVM) && defined(CONFIG_SPE)
OFFSET(VCPU_EVR, kvm_vcpu, arch.evr[0]);
OFFSET(VCPU_ACC, kvm_vcpu, arch.acc);
OFFSET(VCPU_SPEFSCR, kvm_vcpu, arch.spefscr);
OFFSET(VCPU_HOST_SPEFSCR, kvm_vcpu, arch.host_spefscr);
#endif
#ifdef CONFIG_KVM_BOOKE_HV
OFFSET(VCPU_HOST_MAS4, kvm_vcpu, arch.host_mas4);
OFFSET(VCPU_HOST_MAS6, kvm_vcpu, arch.host_mas6);
#endif
#ifdef CONFIG_KVM_XICS
DEFINE(VCPU_XIVE_SAVED_STATE, offsetof(struct kvm_vcpu,
arch.xive_saved_state));
DEFINE(VCPU_XIVE_CAM_WORD, offsetof(struct kvm_vcpu,
arch.xive_cam_word));
DEFINE(VCPU_XIVE_PUSHED, offsetof(struct kvm_vcpu, arch.xive_pushed));
DEFINE(VCPU_XIVE_ESC_ON, offsetof(struct kvm_vcpu, arch.xive_esc_on));
DEFINE(VCPU_XIVE_ESC_RADDR, offsetof(struct kvm_vcpu, arch.xive_esc_raddr));
DEFINE(VCPU_XIVE_ESC_VADDR, offsetof(struct kvm_vcpu, arch.xive_esc_vaddr));
#endif
#ifdef CONFIG_KVM_EXIT_TIMING
OFFSET(VCPU_TIMING_EXIT_TBU, kvm_vcpu, arch.timing_exit.tv32.tbu);
OFFSET(VCPU_TIMING_EXIT_TBL, kvm_vcpu, arch.timing_exit.tv32.tbl);
OFFSET(VCPU_TIMING_LAST_ENTER_TBU, kvm_vcpu, arch.timing_last_enter.tv32.tbu);
OFFSET(VCPU_TIMING_LAST_ENTER_TBL, kvm_vcpu, arch.timing_last_enter.tv32.tbl);
#endif
DEFINE(PPC_DBELL_SERVER, PPC_DBELL_SERVER);
#ifdef CONFIG_PPC_8xx
DEFINE(VIRT_IMMR_BASE, (u64)__fix_to_virt(FIX_IMMR_BASE));
#endif
#ifdef CONFIG_XMON
DEFINE(BPT_SIZE, BPT_SIZE);
#endif
return 0;
}