linux/arch/arm64/include/asm
Dave Martin b3eb56b629 KVM: arm64/sve: Fix SVE trap restoration for non-current tasks
Commit e6b673b ("KVM: arm64: Optimise FPSIMD handling to reduce
guest/host thrashing") attempts to restore the configuration of
userspace SVE trapping via a call to fpsimd_bind_task_to_cpu(), but
the logic for determining when to do this is not correct.

The patch makes the errnoenous assumption that the only task that
may try to enter userspace with the currently loaded FPSIMD/SVE
register content is current.  This may not be the case however:  if
some other user task T is scheduled on the CPU during the execution
of the KVM run loop, and the vcpu does not try to use the registers
in the meantime, then T's state may be left there intact.  If T
happens to be the next task to enter userspace on this CPU then the
hooks for reloading the register state and configuring traps will
be skipped.

(Also, current never has SVE state at this point anyway and should
always have the trap enabled, as a side-effect of the ioctl()
syscall needed to reach the KVM run loop in the first place.)

This patch instead restores the state of the EL0 trap from the
state observed at the most recent vcpu_load(), ensuring that the
trap is set correctly for the loaded context (if any).

Fixes: e6b673b741 ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing")
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-06-21 09:14:44 +01:00
..
xen License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
acenv.h
acpi.h arm64/acpi: Create arch specific cpu to acpi id helper 2018-05-17 17:28:09 +01:00
alternative.h arm64: alternatives: Add dynamic patching feature 2018-03-19 13:03:17 +00:00
arch_gicv3.h irqchip/gic-v3: Probe for SCR_EL3 being clear before resetting AP0Rn 2018-03-22 13:46:18 +00:00
arch_timer.h First batch of KVM changes for 4.15 2017-11-16 13:00:24 -08:00
arm_dsu_pmu.h perf: ARM DynamIQ Shared Unit PMU support 2018-01-02 16:43:12 +00:00
arm-cci.h
asm-bug.h arm64: asm-bug: Renumber macro local labels to avoid clashes 2017-10-25 15:57:15 +01:00
asm-offsets.h
asm-uaccess.h arm64: mm: Add additional parameter to uaccess_ttbr0_disable 2018-01-17 13:57:49 +01:00
assembler.h arm64: assembler: add macros to conditionally yield the NEON under PREEMPT 2018-04-11 18:50:34 +01:00
atomic_ll_sc.h arm64: Remove redundant mov from LL/SC cmpxchg 2017-05-15 18:30:10 +01:00
atomic_lse.h arm64: lse: Add early clobbers to some input/output asm operands 2018-05-21 19:00:36 +01:00
atomic.h locking/atomic: Remove linux/atomic.h:atomic_fetch_or() 2016-06-16 10:48:32 +02:00
barrier.h arm64: Implement array_index_mask_nospec() 2018-02-06 22:53:30 +00:00
bitops.h
bitrev.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
boot.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
brk-imm.h arm64: move brk immediate argument definitions to separate header 2016-02-23 17:43:25 +00:00
bug.h arm64: Add ASM_BUG() 2017-08-08 16:28:13 +01:00
cache.h arm64: Increase ARCH_DMA_MINALIGN to 128 2018-05-15 13:29:55 +01:00
cacheflush.h docs: Fix some broken references 2018-06-15 18:10:01 -03:00
checksum.h arm64: add missing conversion to __wsum in ip_fast_csum() 2017-06-29 16:32:43 +01:00
clocksource.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cmpxchg.h arm64: cmpwait: Clear event register before arming exclusive monitor 2018-05-16 12:21:19 +01:00
compat.h y2038: arm64: Extend sysvipc compat data structures 2018-04-20 16:20:01 +02:00
compiler.h
cpu_ops.h
cpu.h arm64/sve: Probe SVE capabilities and usable vector lengths 2017-11-03 15:24:17 +00:00
cpucaps.h arm64: Add ARCH_WORKAROUND_2 probing 2018-05-31 17:34:38 +01:00
cpufeature.h Small update for KVM. 2018-06-12 11:34:04 -07:00
cpuidle.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cputype.h arm64: Add MIDR encoding for NVIDIA CPUs 2018-05-09 14:28:20 +01:00
current.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
daifflags.h arm64: Move the async/fiq helpers to explicitly set process context flags 2017-11-02 15:55:41 +00:00
dcc.h arm64: dcc: simplify accessors 2016-09-09 11:41:13 +01:00
debug-monitors.h arm64: Add uprobe support 2016-11-07 18:15:21 +00:00
device.h xen/arm,arm64: fix xen_dma_ops after 815dd18 "Consolidate get_dma_ops..." 2017-05-02 11:14:42 +02:00
dma-mapping.h dma-mapping: move dma_mark_clean to dma-direct.h 2018-01-10 16:41:12 +01:00
dmi.h
efi.h efi/arm64: Check whether x18 is preserved by runtime services calls 2018-03-09 08:58:22 +01:00
elf.h arm64: signal: Report signal frame size to userspace via auxv 2018-06-01 15:53:10 +01:00
esr.h arm64: fpsimd: Fix bad si_code for undiagnosed SIGFPE 2018-03-20 10:03:11 +00:00
exception.h arm64: kernel: Prepare for a DISR user 2018-01-16 15:07:12 +00:00
exec.h arm64: suspend: Reconfigure PSTATE after resume from idle 2016-10-20 09:50:54 +01:00
extable.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fb.h
fixmap.h arm64: kaslr: Put kernel vectors address in separate data page 2017-12-11 13:41:20 +00:00
fpsimd.h arm64/sve: Move sve_pffr() to fpsimd.h and make inline 2018-05-25 12:28:29 +01:00
fpsimdmacros.h arm64/sve: Write ZCR_EL1 on context switch only if changed 2018-05-17 18:19:53 +01:00
ftrace.h arm64: Fix misspellings in comments. 2016-03-04 18:19:17 +00:00
futex.h arm64: futex: Mask __user pointers prior to dereference 2018-02-06 22:53:42 +00:00
hardirq.h arm64: kdump: implement machine_crash_shutdown() 2017-04-05 18:29:15 +01:00
hugetlb.h arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables 2018-02-16 18:13:57 +00:00
hw_breakpoint.h arm64: cpufeature: Make ID reg accessor naming less counterintuitive 2017-04-04 16:55:41 +01:00
hwcap.h arm64/HWCAP: Use system wide safe values 2015-10-21 15:35:58 +01:00
hypervisor.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
insn.h arm64; insn: Add encoder for the EXTR instruction 2018-03-19 13:05:10 +00:00
io.h ARM64: Implement pci_remap_cfgspace() interface 2017-04-24 13:53:13 -05:00
irq_work.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irqflags.h arm64: Move the async/fiq helpers to explicitly set process context flags 2017-11-02 15:55:41 +00:00
jump_label.h
kasan.h kasan: clean up KASAN_SHADOW_SCALE_SHIFT usage 2018-02-06 18:32:43 -08:00
Kbuild arch: Remove clkdev.h asm-generic from Kbuild 2018-01-03 09:02:11 -08:00
kernel-pgtable.h arm64: kpti: Make use of nG dependent on arm64_kernel_unmapped_at_el0() 2018-02-06 22:53:14 +00:00
kexec.h arm64: kdump: implement machine_crash_shutdown() 2017-04-05 18:29:15 +01:00
kgdb.h arm64: kgdb: Match pstate size with gdbserver protocol 2016-06-16 19:20:51 +01:00
kprobes.h kprobes: move kprobe declarations to asm-generic/kprobes.h 2017-02-27 18:43:45 -08:00
kvm_arm.h KVM: arm64: Move HCR_INT_OVERRIDE to default HCR_EL2 guest flag 2018-03-19 10:53:10 +00:00
kvm_asm.h Small update for KVM. 2018-06-12 11:34:04 -07:00
kvm_coproc.h
kvm_emulate.h KVM: arm64: Fix order of vcpu_write_sys_reg() arguments 2018-05-04 16:44:54 +01:00
kvm_host.h KVM: arm64/sve: Fix SVE trap restoration for non-current tasks 2018-06-21 09:14:44 +01:00
kvm_hyp.h KVM: arm/arm64: Avoid VGICv3 save/restore on VHE with no IRQs 2018-03-19 10:53:21 +00:00
kvm_mmio.h KVM: arm/arm64: Export mmio_read/write_bus 2016-05-20 15:39:42 +02:00
kvm_mmu.h arm64 updates for 4.18: 2018-06-08 11:10:58 -07:00
linkage.h arm64: relax assembly code alignment from 16 byte to 4 byte 2017-09-18 11:20:19 +01:00
lse.h arm64: lse: Include compiler_types.h and export.h for out-of-line LL/SC 2018-03-27 13:14:49 +01:00
memblock.h
memory.h linux/const.h: move UL() macro to include/linux/const.h 2018-04-11 10:28:38 -07:00
mmu_context.h arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables 2018-02-16 18:13:57 +00:00
mmu.h arm64: KVM: Allow mapping of vectors outside of the RAM region 2018-03-19 13:06:46 +00:00
mmzone.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
module.h arm64/kernel: rename module_emit_adrp_veneer->module_emit_veneer_for_adrp 2018-04-24 19:07:35 +01:00
neon.h arm64: neon: Temporarily add a kernel_mode_begin_partial() definition 2017-08-04 15:10:12 +01:00
numa.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page-def.h arm64: factor out PAGE_* and CONT_* definitions 2017-08-15 18:35:00 +01:00
page.h arm64: factor out PAGE_* and CONT_* definitions 2017-08-15 18:35:00 +01:00
paravirt.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci.h PCI: remove PCI_DMA_BUS_IS_PHYS 2018-05-07 07:15:41 +02:00
percpu.h arm64: move percpu cmpxchg implementation from cmpxchg.h to percpu.h 2018-03-27 13:15:29 +01:00
perf_event.h arm64/bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:41 +01:00
pgalloc.h arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables 2018-02-16 18:13:57 +00:00
pgtable-hwdef.h arm64: kaslr: Set TCR_EL1.NFD1 when CONFIG_RANDOMIZE_BASE=y 2018-03-06 18:52:34 +00:00
pgtable-prot.h KVM changes for 4.16 2018-02-10 13:16:35 -08:00
pgtable-types.h arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
pgtable.h mm: introduce ARCH_HAS_PTE_SPECIAL 2018-06-07 17:34:35 -07:00
probes.h arm64: Remove reference to asm/opcodes.h 2016-12-05 10:42:34 +00:00
proc-fns.h arm64: mm: Move ASID from TTBR0 to TTBR1 2017-12-11 13:40:25 +00:00
processor.h Small update for KVM. 2018-06-12 11:34:04 -07:00
ptdump.h arm64: dump: Add checking for writable and exectuable pages 2016-11-07 18:15:04 +00:00
ptrace.h Merge branch 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core 2017-08-09 15:37:49 +01:00
sdei.h arm64: sdei: Add trampoline code for remapping the kernel 2018-01-14 18:49:50 +00:00
seccomp.h
sections.h arm64: mmu: add the entry trampolines start/end section markers into sections.h 2018-01-14 18:49:50 +00:00
shmparam.h arm64: fix COMPAT_SHMLBA definition for large pages 2015-12-02 14:00:10 +00:00
signal32.h arm64: compat: Remove leftover variable declaration 2017-08-10 18:17:32 +01:00
simd.h arm64: neon: Forbid when irqs are disabled 2017-08-09 15:05:59 +01:00
smp_plat.h
smp.h arm64: kexec: have own crash_smp_send_stop() for crash dump for nonpanic cores 2017-08-21 18:01:04 +01:00
sparsemem.h arm64: add kconfig symbol to configure physical address size 2017-12-22 17:30:33 +00:00
spinlock_types.h locking/qrwlock, arm64: Move rwlock implementation over to qrwlocks 2017-10-25 10:57:25 +02:00
spinlock.h locking/spinlocks/arm64: Remove smp_mb() from arch_spin_is_locked() 2018-05-15 08:11:15 +02:00
stack_pointer.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
stackprotector.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
stacktrace.h arm64: fix unwind_frame() for filtered out fn for function graph tracing 2018-02-23 13:46:38 +00:00
stage2_pgtable-nopmd.h kvm: arm64: Get rid of fake page table levels 2016-04-21 14:58:21 +02:00
stage2_pgtable-nopud.h kvm: arm64: Get rid of fake page table levels 2016-04-21 14:58:21 +02:00
stage2_pgtable.h kvm: arm64: Get rid of fake page table levels 2016-04-21 14:58:21 +02:00
stat.h compat: Move compat_timespec/ timeval to compat_time.h 2018-04-19 13:29:54 +02:00
string.h arm64: uaccess: Implement *_flushcache variants 2017-08-09 12:16:26 +01:00
suspend.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sync_bitops.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
syscall.h
sysreg.h arm64: Introduce sysreg_clear_set() 2018-06-21 09:14:54 +01:00
system_misc.h arm64: Move show_unhandled_signals_ratelimited into traps.c 2018-03-06 18:52:31 +00:00
thread_info.h Small update for KVM. 2018-06-12 11:34:04 -07:00
timex.h arm64: Use physical counter for in-kernel reads when booted in EL2 2017-11-06 16:23:09 +01:00
tlb.h
tlbflush.h arm64: tlbflush: avoid writing RES0 bits 2018-03-28 15:20:17 +01:00
topology.h arm64: topology: divorce MC scheduling domain from core_siblings 2018-05-17 17:28:09 +01:00
traps.h arm64: Introduce arm64_force_sig_info and hook up in arm64_notify_die 2018-03-06 18:52:23 +00:00
uaccess.h arm64: uaccess: Formalise types for access_ok() 2018-02-19 13:59:58 +00:00
unistd32.h Remove compat_sys_getdents64() 2017-04-17 12:52:22 -04:00
unistd.h Remove compat_sys_getdents64() 2017-04-17 12:52:22 -04:00
uprobes.h arm64: Add uprobe support 2016-11-07 18:15:21 +00:00
vdso_datapage.h arm64: Add support for CLOCK_MONOTONIC_RAW in clock_gettime() vDSO 2016-07-12 16:06:32 +01:00
vdso.h
virt.h arm64: capabilities: Change scope of VHE to Boot CPU feature 2018-03-26 18:01:41 +01:00
vmap_stack.h arm64: Add vmap_stack header file 2018-01-13 10:45:03 +00:00
word-at-a-time.h Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00