linux/arch/powerpc/kernel/exceptions-64s.S
Cyril Bur 265e60a170 powerpc/64s: Use emergency stack for kernel TM Bad Thing program checks
When using transactional memory (TM), the CPU can be in one of six
states as far as TM is concerned, encoded in the Machine State
Register (MSR). Certain state transitions are illegal and if attempted
trigger a "TM Bad Thing" type program check exception.

If we ever hit one of these exceptions it's treated as a bug, ie. we
oops, and kill the process and/or panic, depending on configuration.

One case where we can trigger a TM Bad Thing, is when returning to
userspace after a system call or interrupt, using RFID. When this
happens the CPU first restores the user register state, in particular
r1 (the stack pointer) and then attempts to update the MSR. However
the MSR update is not allowed and so we take the program check with
the user register state, but the kernel MSR.

This tricks the exception entry code into thinking we have a bad
kernel stack pointer, because the MSR says we're coming from the
kernel, but r1 is pointing to userspace.

To avoid this we instead always switch to the emergency stack if we
take a TM Bad Thing from the kernel. That way none of the user
register values are used, other than for printing in the oops message.

This is the fix for CVE-2017-1000255.

Fixes: 5d176f751e ("powerpc: tm: Enable transactional memory (TM) lazily for userspace")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Rewrite change log & comments, tweak asm slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-06 22:12:16 +11:00

1717 lines
49 KiB
ArmAsm

/*
* This file contains the 64-bit "server" PowerPC variant
* of the low level exception handling including exception
* vectors, exception return, part of the slb and stab
* handling and other fixed offset specific things.
*
* This file is meant to be #included from head_64.S due to
* position dependent assembly.
*
* Most of this originates from head_64.S and thus has the same
* copyright history.
*
*/
#include <asm/hw_irq.h>
#include <asm/exception-64s.h>
#include <asm/ptrace.h>
#include <asm/cpuidle.h>
#include <asm/head-64.h>
/*
* There are a few constraints to be concerned with.
* - Real mode exceptions code/data must be located at their physical location.
* - Virtual mode exceptions must be mapped at their 0xc000... location.
* - Fixed location code must not call directly beyond the __end_interrupts
* area when built with CONFIG_RELOCATABLE. LOAD_HANDLER / bctr sequence
* must be used.
* - LOAD_HANDLER targets must be within first 64K of physical 0 /
* virtual 0xc00...
* - Conditional branch targets must be within +/-32K of caller.
*
* "Virtual exceptions" run with relocation on (MSR_IR=1, MSR_DR=1), and
* therefore don't have to run in physically located code or rfid to
* virtual mode kernel code. However on relocatable kernels they do have
* to branch to KERNELBASE offset because the rest of the kernel (outside
* the exception vectors) may be located elsewhere.
*
* Virtual exceptions correspond with physical, except their entry points
* are offset by 0xc000000000000000 and also tend to get an added 0x4000
* offset applied. Virtual exceptions are enabled with the Alternate
* Interrupt Location (AIL) bit set in the LPCR. However this does not
* guarantee they will be delivered virtually. Some conditions (see the ISA)
* cause exceptions to be delivered in real mode.
*
* It's impossible to receive interrupts below 0x300 via AIL.
*
* KVM: None of the virtual exceptions are from the guest. Anything that
* escalated to HV=1 from HV=0 is delivered via real mode handlers.
*
*
* We layout physical memory as follows:
* 0x0000 - 0x00ff : Secondary processor spin code
* 0x0100 - 0x18ff : Real mode pSeries interrupt vectors
* 0x1900 - 0x3fff : Real mode trampolines
* 0x4000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
* 0x5900 - 0x6fff : Relon mode trampolines
* 0x7000 - 0x7fff : FWNMI data area
* 0x8000 - .... : Common interrupt handlers, remaining early
* setup code, rest of kernel.
*
* We could reclaim 0x4000-0x42ff for real mode trampolines if the space
* is necessary. Until then it's more consistent to explicitly put VIRT_NONE
* vectors there.
*/
OPEN_FIXED_SECTION(real_vectors, 0x0100, 0x1900)
OPEN_FIXED_SECTION(real_trampolines, 0x1900, 0x4000)
OPEN_FIXED_SECTION(virt_vectors, 0x4000, 0x5900)
OPEN_FIXED_SECTION(virt_trampolines, 0x5900, 0x7000)
#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
/*
* Data area reserved for FWNMI option.
* This address (0x7000) is fixed by the RPA.
* pseries and powernv need to keep the whole page from
* 0x7000 to 0x8000 free for use by the firmware
*/
ZERO_FIXED_SECTION(fwnmi_page, 0x7000, 0x8000)
OPEN_TEXT_SECTION(0x8000)
#else
OPEN_TEXT_SECTION(0x7000)
#endif
USE_FIXED_SECTION(real_vectors)
/*
* This is the start of the interrupt handlers for pSeries
* This code runs with relocation off.
* Code from here to __end_interrupts gets copied down to real
* address 0x100 when we are running a relocatable kernel.
* Therefore any relative branches in this section must only
* branch to labels in this section.
*/
.globl __start_interrupts
__start_interrupts:
/* No virt vectors corresponding with 0x0..0x100 */
EXC_VIRT_NONE(0x4000, 0x100)
#ifdef CONFIG_PPC_P7_NAP
/*
* If running native on arch 2.06 or later, check if we are waking up
* from nap/sleep/winkle, and branch to idle handler. This tests SRR1
* bits 46:47. A non-0 value indicates that we are coming from a power
* saving state. The idle wakeup handler initially runs in real mode,
* but we branch to the 0xc000... address so we can turn on relocation
* with mtmsr.
*/
#define IDLETEST(n) \
BEGIN_FTR_SECTION ; \
mfspr r10,SPRN_SRR1 ; \
rlwinm. r10,r10,47-31,30,31 ; \
beq- 1f ; \
cmpwi cr3,r10,2 ; \
BRANCH_TO_C000(r10, system_reset_idle_common) ; \
1: \
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#else
#define IDLETEST NOTEST
#endif
EXC_REAL_BEGIN(system_reset, 0x100, 0x100)
SET_SCRATCH0(r13)
/*
* MSR_RI is not enabled, because PACA_EXNMI and nmi stack is
* being used, so a nested NMI exception would corrupt it.
*/
EXCEPTION_PROLOG_PSERIES_NORI(PACA_EXNMI, system_reset_common, EXC_STD,
IDLETEST, 0x100)
EXC_REAL_END(system_reset, 0x100, 0x100)
EXC_VIRT_NONE(0x4100, 0x100)
#ifdef CONFIG_PPC_P7_NAP
EXC_COMMON_BEGIN(system_reset_idle_common)
mfspr r12,SPRN_SRR1
b pnv_powersave_wakeup
#endif
EXC_COMMON_BEGIN(system_reset_common)
/*
* Increment paca->in_nmi then enable MSR_RI. SLB or MCE will be able
* to recover, but nested NMI will notice in_nmi and not recover
* because of the use of the NMI stack. in_nmi reentrancy is tested in
* system_reset_exception.
*/
lhz r10,PACA_IN_NMI(r13)
addi r10,r10,1
sth r10,PACA_IN_NMI(r13)
li r10,MSR_RI
mtmsrd r10,1
mr r10,r1
ld r1,PACA_NMI_EMERG_SP(r13)
subi r1,r1,INT_FRAME_SIZE
EXCEPTION_COMMON_NORET_STACK(PACA_EXNMI, 0x100,
system_reset, system_reset_exception,
ADD_NVGPRS;ADD_RECONCILE)
/*
* The stack is no longer in use, decrement in_nmi.
*/
lhz r10,PACA_IN_NMI(r13)
subi r10,r10,1
sth r10,PACA_IN_NMI(r13)
b ret_from_except
#ifdef CONFIG_PPC_PSERIES
/*
* Vectors for the FWNMI option. Share common code.
*/
TRAMP_REAL_BEGIN(system_reset_fwnmi)
SET_SCRATCH0(r13) /* save r13 */
/* See comment at system_reset exception */
EXCEPTION_PROLOG_PSERIES_NORI(PACA_EXNMI, system_reset_common,
EXC_STD, NOTEST, 0x100)
#endif /* CONFIG_PPC_PSERIES */
EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
/* This is moved out of line as it can be patched by FW, but
* some code path might still want to branch into the original
* vector
*/
SET_SCRATCH0(r13) /* save r13 */
EXCEPTION_PROLOG_0(PACA_EXMC)
BEGIN_FTR_SECTION
b machine_check_powernv_early
FTR_SECTION_ELSE
b machine_check_pSeries_0
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
EXC_REAL_END(machine_check, 0x200, 0x100)
EXC_VIRT_NONE(0x4200, 0x100)
TRAMP_REAL_BEGIN(machine_check_powernv_early)
BEGIN_FTR_SECTION
EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
/*
* Register contents:
* R13 = PACA
* R9 = CR
* Original R9 to R13 is saved on PACA_EXMC
*
* Switch to mc_emergency stack and handle re-entrancy (we limit
* the nested MCE upto level 4 to avoid stack overflow).
* Save MCE registers srr1, srr0, dar and dsisr and then set ME=1
*
* We use paca->in_mce to check whether this is the first entry or
* nested machine check. We increment paca->in_mce to track nested
* machine checks.
*
* If this is the first entry then set stack pointer to
* paca->mc_emergency_sp, otherwise r1 is already pointing to
* stack frame on mc_emergency stack.
*
* NOTE: We are here with MSR_ME=0 (off), which means we risk a
* checkstop if we get another machine check exception before we do
* rfid with MSR_ME=1.
*
* This interrupt can wake directly from idle. If that is the case,
* the machine check is handled then the idle wakeup code is called
* to restore state. In that case, the POWER9 DD1 idle PACA workaround
* is not applied in the early machine check code, which will cause
* bugs.
*/
mr r11,r1 /* Save r1 */
lhz r10,PACA_IN_MCE(r13)
cmpwi r10,0 /* Are we in nested machine check */
bne 0f /* Yes, we are. */
/* First machine check entry */
ld r1,PACAMCEMERGSP(r13) /* Use MC emergency stack */
0: subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
addi r10,r10,1 /* increment paca->in_mce */
sth r10,PACA_IN_MCE(r13)
/* Limit nested MCE to level 4 to avoid stack overflow */
cmpwi r10,4
bgt 2f /* Check if we hit limit of 4 */
std r11,GPR1(r1) /* Save r1 on the stack. */
std r11,0(r1) /* make stack chain pointer */
mfspr r11,SPRN_SRR0 /* Save SRR0 */
std r11,_NIP(r1)
mfspr r11,SPRN_SRR1 /* Save SRR1 */
std r11,_MSR(r1)
mfspr r11,SPRN_DAR /* Save DAR */
std r11,_DAR(r1)
mfspr r11,SPRN_DSISR /* Save DSISR */
std r11,_DSISR(r1)
std r9,_CCR(r1) /* Save CR in stackframe */
/* Save r9 through r13 from EXMC save area to stack frame. */
EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
mfmsr r11 /* get MSR value */
ori r11,r11,MSR_ME /* turn on ME bit */
ori r11,r11,MSR_RI /* turn on RI bit */
LOAD_HANDLER(r12, machine_check_handle_early)
1: mtspr SPRN_SRR0,r12
mtspr SPRN_SRR1,r11
rfid
b . /* prevent speculative execution */
2:
/* Stack overflow. Stay on emergency stack and panic.
* Keep the ME bit off while panic-ing, so that if we hit
* another machine check we checkstop.
*/
addi r1,r1,INT_FRAME_SIZE /* go back to previous stack frame */
ld r11,PACAKMSR(r13)
LOAD_HANDLER(r12, unrecover_mce)
li r10,MSR_ME
andc r11,r11,r10 /* Turn off MSR_ME */
b 1b
b . /* prevent speculative execution */
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
TRAMP_REAL_BEGIN(machine_check_pSeries)
.globl machine_check_fwnmi
machine_check_fwnmi:
SET_SCRATCH0(r13) /* save r13 */
EXCEPTION_PROLOG_0(PACA_EXMC)
machine_check_pSeries_0:
EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST_PR, 0x200)
/*
* MSR_RI is not enabled, because PACA_EXMC is being used, so a
* nested machine check corrupts it. machine_check_common enables
* MSR_RI.
*/
EXCEPTION_PROLOG_PSERIES_1_NORI(machine_check_common, EXC_STD)
TRAMP_KVM_SKIP(PACA_EXMC, 0x200)
EXC_COMMON_BEGIN(machine_check_common)
/*
* Machine check is different because we use a different
* save area: PACA_EXMC instead of PACA_EXGEN.
*/
mfspr r10,SPRN_DAR
std r10,PACA_EXMC+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXMC+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
FINISH_NAP
RECONCILE_IRQ_STATE(r10, r11)
ld r3,PACA_EXMC+EX_DAR(r13)
lwz r4,PACA_EXMC+EX_DSISR(r13)
/* Enable MSR_RI when finished with PACA_EXMC */
li r10,MSR_RI
mtmsrd r10,1
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_exception
b ret_from_except
#define MACHINE_CHECK_HANDLER_WINDUP \
/* Clear MSR_RI before setting SRR0 and SRR1. */\
li r0,MSR_RI; \
mfmsr r9; /* get MSR value */ \
andc r9,r9,r0; \
mtmsrd r9,1; /* Clear MSR_RI */ \
/* Move original SRR0 and SRR1 into the respective regs */ \
ld r9,_MSR(r1); \
mtspr SPRN_SRR1,r9; \
ld r3,_NIP(r1); \
mtspr SPRN_SRR0,r3; \
ld r9,_CTR(r1); \
mtctr r9; \
ld r9,_XER(r1); \
mtxer r9; \
ld r9,_LINK(r1); \
mtlr r9; \
REST_GPR(0, r1); \
REST_8GPRS(2, r1); \
REST_GPR(10, r1); \
ld r11,_CCR(r1); \
mtcr r11; \
/* Decrement paca->in_mce. */ \
lhz r12,PACA_IN_MCE(r13); \
subi r12,r12,1; \
sth r12,PACA_IN_MCE(r13); \
REST_GPR(11, r1); \
REST_2GPRS(12, r1); \
/* restore original r1. */ \
ld r1,GPR1(r1)
#ifdef CONFIG_PPC_P7_NAP
/*
* This is an idle wakeup. Low level machine check has already been
* done. Queue the event then call the idle code to do the wake up.
*/
EXC_COMMON_BEGIN(machine_check_idle_common)
bl machine_check_queue_event
/*
* We have not used any non-volatile GPRs here, and as a rule
* most exception code including machine check does not.
* Therefore PACA_NAPSTATELOST does not need to be set. Idle
* wakeup will restore volatile registers.
*
* Load the original SRR1 into r3 for pnv_powersave_wakeup_mce.
*
* Then decrement MCE nesting after finishing with the stack.
*/
ld r3,_MSR(r1)
lhz r11,PACA_IN_MCE(r13)
subi r11,r11,1
sth r11,PACA_IN_MCE(r13)
/* Turn off the RI bit because SRR1 is used by idle wakeup code. */
/* Recoverability could be improved by reducing the use of SRR1. */
li r11,0
mtmsrd r11,1
b pnv_powersave_wakeup_mce
#endif
/*
* Handle machine check early in real mode. We come here with
* ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
*/
EXC_COMMON_BEGIN(machine_check_handle_early)
std r0,GPR0(r1) /* Save r0 */
EXCEPTION_PROLOG_COMMON_3(0x200)
bl save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_early
std r3,RESULT(r1) /* Save result */
ld r12,_MSR(r1)
#ifdef CONFIG_PPC_P7_NAP
/*
* Check if thread was in power saving mode. We come here when any
* of the following is true:
* a. thread wasn't in power saving mode
* b. thread was in power saving mode with no state loss,
* supervisor state loss or hypervisor state loss.
*
* Go back to nap/sleep/winkle mode again if (b) is true.
*/
BEGIN_FTR_SECTION
rlwinm. r11,r12,47-31,30,31
bne machine_check_idle_common
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#endif
/*
* Check if we are coming from hypervisor userspace. If yes then we
* continue in host kernel in V mode to deliver the MC event.
*/
rldicl. r11,r12,4,63 /* See if MC hit while in HV mode. */
beq 5f
andi. r11,r12,MSR_PR /* See if coming from user. */
bne 9f /* continue in V mode if we are. */
5:
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
/*
* We are coming from kernel context. Check if we are coming from
* guest. if yes, then we can continue. We will fall through
* do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
*/
lbz r11,HSTATE_IN_GUEST(r13)
cmpwi r11,0 /* Check if coming from guest */
bne 9f /* continue if we are. */
#endif
/*
* At this point we are not sure about what context we come from.
* Queue up the MCE event and return from the interrupt.
* But before that, check if this is an un-recoverable exception.
* If yes, then stay on emergency stack and panic.
*/
andi. r11,r12,MSR_RI
bne 2f
1: mfspr r11,SPRN_SRR0
LOAD_HANDLER(r10,unrecover_mce)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
/*
* We are going down. But there are chances that we might get hit by
* another MCE during panic path and we may run into unstable state
* with no way out. Hence, turn ME bit off while going down, so that
* when another MCE is hit during panic path, system will checkstop
* and hypervisor will get restarted cleanly by SP.
*/
li r3,MSR_ME
andc r10,r10,r3 /* Turn off MSR_ME */
mtspr SPRN_SRR1,r10
rfid
b .
2:
/*
* Check if we have successfully handled/recovered from error, if not
* then stay on emergency stack and panic.
*/
ld r3,RESULT(r1) /* Load result */
cmpdi r3,0 /* see if we handled MCE successfully */
beq 1b /* if !handled then panic */
/*
* Return from MC interrupt.
* Queue up the MCE event so that we can log it later, while
* returning from kernel or opal call.
*/
bl machine_check_queue_event
MACHINE_CHECK_HANDLER_WINDUP
rfid
9:
/* Deliver the machine check to host kernel in V mode. */
MACHINE_CHECK_HANDLER_WINDUP
b machine_check_pSeries
EXC_COMMON_BEGIN(unrecover_mce)
/* Invoke machine_check_exception to print MCE event and panic. */
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_exception
/*
* We will not reach here. Even if we did, there is no way out. Call
* unrecoverable_exception and die.
*/
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl unrecoverable_exception
b 1b
EXC_REAL(data_access, 0x300, 0x80)
EXC_VIRT(data_access, 0x4300, 0x80, 0x300)
TRAMP_KVM_SKIP(PACA_EXGEN, 0x300)
EXC_COMMON_BEGIN(data_access_common)
/*
* Here r13 points to the paca, r9 contains the saved CR,
* SRR0 and SRR1 are saved in r11 and r12,
* r9 - r13 are saved in paca->exgen.
*/
mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
RECONCILE_IRQ_STATE(r10, r11)
ld r12,_MSR(r1)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
li r5,0x300
std r3,_DAR(r1)
std r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
b do_hash_page /* Try to handle as hpte fault */
MMU_FTR_SECTION_ELSE
b handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80)
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x380)
mr r12,r3 /* save r3 */
mfspr r3,SPRN_DAR
mfspr r11,SPRN_SRR1
crset 4*cr6+eq
BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_REAL_END(data_access_slb, 0x380, 0x80)
EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
mr r12,r3 /* save r3 */
mfspr r3,SPRN_DAR
mfspr r11,SPRN_SRR1
crset 4*cr6+eq
BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
TRAMP_KVM_SKIP(PACA_EXSLB, 0x380)
EXC_REAL(instruction_access, 0x400, 0x80)
EXC_VIRT(instruction_access, 0x4400, 0x80, 0x400)
TRAMP_KVM(PACA_EXGEN, 0x400)
EXC_COMMON_BEGIN(instruction_access_common)
EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
RECONCILE_IRQ_STATE(r10, r11)
ld r12,_MSR(r1)
ld r3,_NIP(r1)
andis. r4,r12,DSISR_BAD_FAULT_64S@h
li r5,0x400
std r3,_DAR(r1)
std r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
b do_hash_page /* Try to handle as hpte fault */
MMU_FTR_SECTION_ELSE
b handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80)
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
mr r12,r3 /* save r3 */
mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
mfspr r11,SPRN_SRR1
crclr 4*cr6+eq
BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_REAL_END(instruction_access_slb, 0x480, 0x80)
EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
mr r12,r3 /* save r3 */
mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
mfspr r11,SPRN_SRR1
crclr 4*cr6+eq
BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
TRAMP_KVM(PACA_EXSLB, 0x480)
/*
* This handler is used by the 0x380 and 0x480 SLB miss interrupts, as well as
* the virtual mode 0x4380 and 0x4480 interrupts if AIL is enabled.
*/
EXC_COMMON_BEGIN(slb_miss_common)
/*
* r13 points to the PACA, r9 contains the saved CR,
* r12 contains the saved r3,
* r11 contain the saved SRR1, SRR0 is still ready for return
* r3 has the faulting address
* r9 - r13 are saved in paca->exslb.
* cr6.eq is set for a D-SLB miss, clear for a I-SLB miss
* We assume we aren't going to take any exceptions during this
* procedure.
*/
mflr r10
stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
/*
* Test MSR_RI before calling slb_allocate_realmode, because the
* MSR in r11 gets clobbered. However we still want to allocate
* SLB in case MSR_RI=0, to minimise the risk of getting stuck in
* recursive SLB faults. So use cr5 for this, which is preserved.
*/
andi. r11,r11,MSR_RI /* check for unrecoverable exception */
cmpdi cr5,r11,MSR_RI
crset 4*cr0+eq
#ifdef CONFIG_PPC_STD_MMU_64
BEGIN_MMU_FTR_SECTION
bl slb_allocate
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
#endif
ld r10,PACA_EXSLB+EX_LR(r13)
lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
mtlr r10
beq- 8f /* if bad address, make full stack frame */
bne- cr5,2f /* if unrecoverable exception, oops */
/* All done -- return from exception. */
.machine push
.machine "power4"
mtcrf 0x80,r9
mtcrf 0x04,r9 /* MSR[RI] indication is in cr5 */
mtcrf 0x02,r9 /* I/D indication is in cr6 */
mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */
.machine pop
RESTORE_CTR(r9, PACA_EXSLB)
RESTORE_PPR_PACA(PACA_EXSLB, r9)
mr r3,r12
ld r9,PACA_EXSLB+EX_R9(r13)
ld r10,PACA_EXSLB+EX_R10(r13)
ld r11,PACA_EXSLB+EX_R11(r13)
ld r12,PACA_EXSLB+EX_R12(r13)
ld r13,PACA_EXSLB+EX_R13(r13)
rfid
b . /* prevent speculative execution */
2: std r3,PACA_EXSLB+EX_DAR(r13)
mr r3,r12
mfspr r11,SPRN_SRR0
mfspr r12,SPRN_SRR1
LOAD_HANDLER(r10,unrecov_slb)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
mtspr SPRN_SRR1,r10
rfid
b .
8: std r3,PACA_EXSLB+EX_DAR(r13)
mr r3,r12
mfspr r11,SPRN_SRR0
mfspr r12,SPRN_SRR1
LOAD_HANDLER(r10,bad_addr_slb)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
mtspr SPRN_SRR1,r10
rfid
b .
EXC_COMMON_BEGIN(unrecov_slb)
EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
RECONCILE_IRQ_STATE(r10, r11)
bl save_nvgprs
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl unrecoverable_exception
b 1b
EXC_COMMON_BEGIN(bad_addr_slb)
EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
RECONCILE_IRQ_STATE(r10, r11)
ld r3, PACA_EXSLB+EX_DAR(r13)
std r3, _DAR(r1)
beq cr6, 2f
li r10, 0x480 /* fix trap number for I-SLB miss */
std r10, _TRAP(r1)
2: bl save_nvgprs
addi r3, r1, STACK_FRAME_OVERHEAD
bl slb_miss_bad_addr
b ret_from_except
EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
.globl hardware_interrupt_hv;
hardware_interrupt_hv:
BEGIN_FTR_SECTION
_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common,
EXC_HV, SOFTEN_TEST_HV)
FTR_SECTION_ELSE
_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common,
EXC_STD, SOFTEN_TEST_PR)
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
EXC_REAL_END(hardware_interrupt, 0x500, 0x100)
EXC_VIRT_BEGIN(hardware_interrupt, 0x4500, 0x100)
.globl hardware_interrupt_relon_hv;
hardware_interrupt_relon_hv:
BEGIN_FTR_SECTION
_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_HV, SOFTEN_TEST_HV)
FTR_SECTION_ELSE
_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_STD, SOFTEN_TEST_PR)
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
EXC_VIRT_END(hardware_interrupt, 0x4500, 0x100)
TRAMP_KVM(PACA_EXGEN, 0x500)
TRAMP_KVM_HV(PACA_EXGEN, 0x500)
EXC_COMMON_ASYNC(hardware_interrupt_common, 0x500, do_IRQ)
EXC_REAL(alignment, 0x600, 0x100)
EXC_VIRT(alignment, 0x4600, 0x100, 0x600)
TRAMP_KVM(PACA_EXGEN, 0x600)
EXC_COMMON_BEGIN(alignment_common)
mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl alignment_exception
b ret_from_except
EXC_REAL(program_check, 0x700, 0x100)
EXC_VIRT(program_check, 0x4700, 0x100, 0x700)
TRAMP_KVM(PACA_EXGEN, 0x700)
EXC_COMMON_BEGIN(program_check_common)
/*
* It's possible to receive a TM Bad Thing type program check with
* userspace register values (in particular r1), but with SRR1 reporting
* that we came from the kernel. Normally that would confuse the bad
* stack logic, and we would report a bad kernel stack pointer. Instead
* we switch to the emergency stack if we're taking a TM Bad Thing from
* the kernel.
*/
li r10,MSR_PR /* Build a mask of MSR_PR .. */
oris r10,r10,0x200000@h /* .. and SRR1_PROGTM */
and r10,r10,r12 /* Mask SRR1 with that. */
srdi r10,r10,8 /* Shift it so we can compare */
cmpldi r10,(0x200000 >> 8) /* .. with an immediate. */
bne 1f /* If != go to normal path. */
/* SRR1 had PR=0 and SRR1_PROGTM=1, so use the emergency stack */
andi. r10,r12,MSR_PR; /* Set CR0 correctly for label */
/* 3 in EXCEPTION_PROLOG_COMMON */
mr r10,r1 /* Save r1 */
ld r1,PACAEMERGSP(r13) /* Use emergency stack */
subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
b 3f /* Jump into the macro !! */
1: EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl program_check_exception
b ret_from_except
EXC_REAL(fp_unavailable, 0x800, 0x100)
EXC_VIRT(fp_unavailable, 0x4800, 0x100, 0x800)
TRAMP_KVM(PACA_EXGEN, 0x800)
EXC_COMMON_BEGIN(fp_unavailable_common)
EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
bne 1f /* if from user, just load it up */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl kernel_fp_unavailable_exception
BUG_OPCODE
1:
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION
/* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
* transaction), go do TM stuff
*/
rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
bne- 2f
END_FTR_SECTION_IFSET(CPU_FTR_TM)
#endif
bl load_up_fpu
b fast_exception_return
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2: /* User process was in a transaction */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl fp_unavailable_tm
b ret_from_except
#endif
EXC_REAL_MASKABLE(decrementer, 0x900, 0x80)
EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x80, 0x900)
TRAMP_KVM(PACA_EXGEN, 0x900)
EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt)
EXC_REAL_HV(hdecrementer, 0x980, 0x80)
EXC_VIRT_HV(hdecrementer, 0x4980, 0x80, 0x980)
TRAMP_KVM_HV(PACA_EXGEN, 0x980)
EXC_COMMON(hdecrementer_common, 0x980, hdec_interrupt)
EXC_REAL_MASKABLE(doorbell_super, 0xa00, 0x100)
EXC_VIRT_MASKABLE(doorbell_super, 0x4a00, 0x100, 0xa00)
TRAMP_KVM(PACA_EXGEN, 0xa00)
#ifdef CONFIG_PPC_DOORBELL
EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, doorbell_exception)
#else
EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, unknown_exception)
#endif
EXC_REAL(trap_0b, 0xb00, 0x100)
EXC_VIRT(trap_0b, 0x4b00, 0x100, 0xb00)
TRAMP_KVM(PACA_EXGEN, 0xb00)
EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)
/*
* system call / hypercall (0xc00, 0x4c00)
*
* The system call exception is invoked with "sc 0" and does not alter HV bit.
* There is support for kernel code to invoke system calls but there are no
* in-tree users.
*
* The hypercall is invoked with "sc 1" and sets HV=1.
*
* In HPT, sc 1 always goes to 0xc00 real mode. In RADIX, sc 1 can go to
* 0x4c00 virtual mode.
*
* Call convention:
*
* syscall register convention is in Documentation/powerpc/syscall64-abi.txt
*
* For hypercalls, the register convention is as follows:
* r0 volatile
* r1-2 nonvolatile
* r3 volatile parameter and return value for status
* r4-r10 volatile input and output value
* r11 volatile hypercall number and output value
* r12 volatile input and output value
* r13-r31 nonvolatile
* LR nonvolatile
* CTR volatile
* XER volatile
* CR0-1 CR5-7 volatile
* CR2-4 nonvolatile
* Other registers nonvolatile
*
* The intersection of volatile registers that don't contain possible
* inputs is: cr0, xer, ctr. We may use these as scratch regs upon entry
* without saving, though xer is not a good idea to use, as hardware may
* interpret some bits so it may be costly to change them.
*/
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
/*
* There is a little bit of juggling to get syscall and hcall
* working well. Save r13 in ctr to avoid using SPRG scratch
* register.
*
* Userspace syscalls have already saved the PPR, hcalls must save
* it before setting HMT_MEDIUM.
*/
#define SYSCALL_KVMTEST \
mtctr r13; \
GET_PACA(r13); \
std r10,PACA_EXGEN+EX_R10(r13); \
KVMTEST_PR(0xc00); /* uses r10, branch to do_kvm_0xc00_system_call */ \
HMT_MEDIUM; \
mfctr r9;
#else
#define SYSCALL_KVMTEST \
HMT_MEDIUM; \
mr r9,r13; \
GET_PACA(r13);
#endif
#define LOAD_SYSCALL_HANDLER(reg) \
__LOAD_HANDLER(reg, system_call_common)
#define SYSCALL_FASTENDIAN_TEST \
BEGIN_FTR_SECTION \
cmpdi r0,0x1ebe ; \
beq- 1f ; \
END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \
/*
* After SYSCALL_KVMTEST, we reach here with PACA in r13, r13 in r9,
* and HMT_MEDIUM.
*/
#define SYSCALL_REAL \
mfspr r11,SPRN_SRR0 ; \
mfspr r12,SPRN_SRR1 ; \
LOAD_SYSCALL_HANDLER(r10) ; \
mtspr SPRN_SRR0,r10 ; \
ld r10,PACAKMSR(r13) ; \
mtspr SPRN_SRR1,r10 ; \
rfid ; \
b . ; /* prevent speculative execution */
#define SYSCALL_FASTENDIAN \
/* Fast LE/BE switch system call */ \
1: mfspr r12,SPRN_SRR1 ; \
xori r12,r12,MSR_LE ; \
mtspr SPRN_SRR1,r12 ; \
mr r13,r9 ; \
rfid ; /* return to userspace */ \
b . ; /* prevent speculative execution */
#if defined(CONFIG_RELOCATABLE)
/*
* We can't branch directly so we do it via the CTR which
* is volatile across system calls.
*/
#define SYSCALL_VIRT \
LOAD_SYSCALL_HANDLER(r10) ; \
mtctr r10 ; \
mfspr r11,SPRN_SRR0 ; \
mfspr r12,SPRN_SRR1 ; \
li r10,MSR_RI ; \
mtmsrd r10,1 ; \
bctr ;
#else
/* We can branch directly */
#define SYSCALL_VIRT \
mfspr r11,SPRN_SRR0 ; \
mfspr r12,SPRN_SRR1 ; \
li r10,MSR_RI ; \
mtmsrd r10,1 ; /* Set RI (EE=0) */ \
b system_call_common ;
#endif
EXC_REAL_BEGIN(system_call, 0xc00, 0x100)
SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
SYSCALL_FASTENDIAN_TEST
SYSCALL_REAL
SYSCALL_FASTENDIAN
EXC_REAL_END(system_call, 0xc00, 0x100)
EXC_VIRT_BEGIN(system_call, 0x4c00, 0x100)
SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
SYSCALL_FASTENDIAN_TEST
SYSCALL_VIRT
SYSCALL_FASTENDIAN
EXC_VIRT_END(system_call, 0x4c00, 0x100)
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
/*
* This is a hcall, so register convention is as above, with these
* differences:
* r13 = PACA
* ctr = orig r13
* orig r10 saved in PACA
*/
TRAMP_KVM_BEGIN(do_kvm_0xc00)
/*
* Save the PPR (on systems that support it) before changing to
* HMT_MEDIUM. That allows the KVM code to save that value into the
* guest state (it is the guest's PPR value).
*/
OPT_GET_SPR(r10, SPRN_PPR, CPU_FTR_HAS_PPR)
HMT_MEDIUM
OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r10, CPU_FTR_HAS_PPR)
mfctr r10
SET_SCRATCH0(r10)
std r9,PACA_EXGEN+EX_R9(r13)
mfcr r9
KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)
#endif
EXC_REAL(single_step, 0xd00, 0x100)
EXC_VIRT(single_step, 0x4d00, 0x100, 0xd00)
TRAMP_KVM(PACA_EXGEN, 0xd00)
EXC_COMMON(single_step_common, 0xd00, single_step_exception)
EXC_REAL_OOL_HV(h_data_storage, 0xe00, 0x20)
EXC_VIRT_OOL_HV(h_data_storage, 0x4e00, 0x20, 0xe00)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0xe00)
EXC_COMMON_BEGIN(h_data_storage_common)
mfspr r10,SPRN_HDAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_HDSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0xe00, PACA_EXGEN)
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl unknown_exception
b ret_from_except
EXC_REAL_OOL_HV(h_instr_storage, 0xe20, 0x20)
EXC_VIRT_OOL_HV(h_instr_storage, 0x4e20, 0x20, 0xe20)
TRAMP_KVM_HV(PACA_EXGEN, 0xe20)
EXC_COMMON(h_instr_storage_common, 0xe20, unknown_exception)
EXC_REAL_OOL_HV(emulation_assist, 0xe40, 0x20)
EXC_VIRT_OOL_HV(emulation_assist, 0x4e40, 0x20, 0xe40)
TRAMP_KVM_HV(PACA_EXGEN, 0xe40)
EXC_COMMON(emulation_assist_common, 0xe40, emulation_assist_interrupt)
/*
* hmi_exception trampoline is a special case. It jumps to hmi_exception_early
* first, and then eventaully from there to the trampoline to get into virtual
* mode.
*/
__EXC_REAL_OOL_HV_DIRECT(hmi_exception, 0xe60, 0x20, hmi_exception_early)
__TRAMP_REAL_OOL_MASKABLE_HV(hmi_exception, 0xe60)
EXC_VIRT_NONE(0x4e60, 0x20)
TRAMP_KVM_HV(PACA_EXGEN, 0xe60)
TRAMP_REAL_BEGIN(hmi_exception_early)
EXCEPTION_PROLOG_1(PACA_EXGEN, KVMTEST_HV, 0xe60)
mr r10,r1 /* Save r1 */
ld r1,PACAEMERGSP(r13) /* Use emergency stack for realmode */
subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
mfspr r11,SPRN_HSRR0 /* Save HSRR0 */
mfspr r12,SPRN_HSRR1 /* Save HSRR1 */
EXCEPTION_PROLOG_COMMON_1()
EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
EXCEPTION_PROLOG_COMMON_3(0xe60)
addi r3,r1,STACK_FRAME_OVERHEAD
BRANCH_LINK_TO_FAR(hmi_exception_realmode) /* Function call ABI */
/* Windup the stack. */
/* Move original HSRR0 and HSRR1 into the respective regs */
ld r9,_MSR(r1)
mtspr SPRN_HSRR1,r9
ld r3,_NIP(r1)
mtspr SPRN_HSRR0,r3
ld r9,_CTR(r1)
mtctr r9
ld r9,_XER(r1)
mtxer r9
ld r9,_LINK(r1)
mtlr r9
REST_GPR(0, r1)
REST_8GPRS(2, r1)
REST_GPR(10, r1)
ld r11,_CCR(r1)
mtcr r11
REST_GPR(11, r1)
REST_2GPRS(12, r1)
/* restore original r1. */
ld r1,GPR1(r1)
/*
* Go to virtual mode and pull the HMI event information from
* firmware.
*/
.globl hmi_exception_after_realmode
hmi_exception_after_realmode:
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b tramp_real_hmi_exception
EXC_COMMON_ASYNC(hmi_exception_common, 0xe60, handle_hmi_exception)
EXC_REAL_OOL_MASKABLE_HV(h_doorbell, 0xe80, 0x20)
EXC_VIRT_OOL_MASKABLE_HV(h_doorbell, 0x4e80, 0x20, 0xe80)
TRAMP_KVM_HV(PACA_EXGEN, 0xe80)
#ifdef CONFIG_PPC_DOORBELL
EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, doorbell_exception)
#else
EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, unknown_exception)
#endif
EXC_REAL_OOL_MASKABLE_HV(h_virt_irq, 0xea0, 0x20)
EXC_VIRT_OOL_MASKABLE_HV(h_virt_irq, 0x4ea0, 0x20, 0xea0)
TRAMP_KVM_HV(PACA_EXGEN, 0xea0)
EXC_COMMON_ASYNC(h_virt_irq_common, 0xea0, do_IRQ)
EXC_REAL_NONE(0xec0, 0x20)
EXC_VIRT_NONE(0x4ec0, 0x20)
EXC_REAL_NONE(0xee0, 0x20)
EXC_VIRT_NONE(0x4ee0, 0x20)
EXC_REAL_OOL(performance_monitor, 0xf00, 0x20)
EXC_VIRT_OOL(performance_monitor, 0x4f00, 0x20, 0xf00)
TRAMP_KVM(PACA_EXGEN, 0xf00)
EXC_COMMON_ASYNC(performance_monitor_common, 0xf00, performance_monitor_exception)
EXC_REAL_OOL(altivec_unavailable, 0xf20, 0x20)
EXC_VIRT_OOL(altivec_unavailable, 0x4f20, 0x20, 0xf20)
TRAMP_KVM(PACA_EXGEN, 0xf20)
EXC_COMMON_BEGIN(altivec_unavailable_common)
EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
beq 1f
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION_NESTED(69)
/* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
* transaction), go do TM stuff
*/
rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
bne- 2f
END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
#endif
bl load_up_altivec
b fast_exception_return
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2: /* User process was in a transaction */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl altivec_unavailable_tm
b ret_from_except
#endif
1:
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl altivec_unavailable_exception
b ret_from_except
EXC_REAL_OOL(vsx_unavailable, 0xf40, 0x20)
EXC_VIRT_OOL(vsx_unavailable, 0x4f40, 0x20, 0xf40)
TRAMP_KVM(PACA_EXGEN, 0xf40)
EXC_COMMON_BEGIN(vsx_unavailable_common)
EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
beq 1f
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION_NESTED(69)
/* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
* transaction), go do TM stuff
*/
rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
bne- 2f
END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
#endif
b load_up_vsx
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2: /* User process was in a transaction */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl vsx_unavailable_tm
b ret_from_except
#endif
1:
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl vsx_unavailable_exception
b ret_from_except
EXC_REAL_OOL(facility_unavailable, 0xf60, 0x20)
EXC_VIRT_OOL(facility_unavailable, 0x4f60, 0x20, 0xf60)
TRAMP_KVM(PACA_EXGEN, 0xf60)
EXC_COMMON(facility_unavailable_common, 0xf60, facility_unavailable_exception)
EXC_REAL_OOL_HV(h_facility_unavailable, 0xf80, 0x20)
EXC_VIRT_OOL_HV(h_facility_unavailable, 0x4f80, 0x20, 0xf80)
TRAMP_KVM_HV(PACA_EXGEN, 0xf80)
EXC_COMMON(h_facility_unavailable_common, 0xf80, facility_unavailable_exception)
EXC_REAL_NONE(0xfa0, 0x20)
EXC_VIRT_NONE(0x4fa0, 0x20)
EXC_REAL_NONE(0xfc0, 0x20)
EXC_VIRT_NONE(0x4fc0, 0x20)
EXC_REAL_NONE(0xfe0, 0x20)
EXC_VIRT_NONE(0x4fe0, 0x20)
EXC_REAL_NONE(0x1000, 0x100)
EXC_VIRT_NONE(0x5000, 0x100)
EXC_REAL_NONE(0x1100, 0x100)
EXC_VIRT_NONE(0x5100, 0x100)
#ifdef CONFIG_CBE_RAS
EXC_REAL_HV(cbe_system_error, 0x1200, 0x100)
EXC_VIRT_NONE(0x5200, 0x100)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1200)
EXC_COMMON(cbe_system_error_common, 0x1200, cbe_system_error_exception)
#else /* CONFIG_CBE_RAS */
EXC_REAL_NONE(0x1200, 0x100)
EXC_VIRT_NONE(0x5200, 0x100)
#endif
EXC_REAL(instruction_breakpoint, 0x1300, 0x100)
EXC_VIRT(instruction_breakpoint, 0x5300, 0x100, 0x1300)
TRAMP_KVM_SKIP(PACA_EXGEN, 0x1300)
EXC_COMMON(instruction_breakpoint_common, 0x1300, instruction_breakpoint_exception)
EXC_REAL_NONE(0x1400, 0x100)
EXC_VIRT_NONE(0x5400, 0x100)
EXC_REAL_BEGIN(denorm_exception_hv, 0x1500, 0x100)
mtspr SPRN_SPRG_HSCRATCH0,r13
EXCEPTION_PROLOG_0(PACA_EXGEN)
EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0x1500)
#ifdef CONFIG_PPC_DENORMALISATION
mfspr r10,SPRN_HSRR1
mfspr r11,SPRN_HSRR0 /* save HSRR0 */
andis. r10,r10,(HSRR1_DENORM)@h /* denorm? */
addi r11,r11,-4 /* HSRR0 is next instruction */
bne+ denorm_assist
#endif
KVMTEST_PR(0x1500)
EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
EXC_REAL_END(denorm_exception_hv, 0x1500, 0x100)
#ifdef CONFIG_PPC_DENORMALISATION
EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100)
b exc_real_0x1500_denorm_exception_hv
EXC_VIRT_END(denorm_exception, 0x5500, 0x100)
#else
EXC_VIRT_NONE(0x5500, 0x100)
#endif
TRAMP_KVM_SKIP(PACA_EXGEN, 0x1500)
#ifdef CONFIG_PPC_DENORMALISATION
TRAMP_REAL_BEGIN(denorm_assist)
BEGIN_FTR_SECTION
/*
* To denormalise we need to move a copy of the register to itself.
* For POWER6 do that here for all FP regs.
*/
mfmsr r10
ori r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
xori r10,r10,(MSR_FE0|MSR_FE1)
mtmsrd r10
sync
#define FMR2(n) fmr (n), (n) ; fmr n+1, n+1
#define FMR4(n) FMR2(n) ; FMR2(n+2)
#define FMR8(n) FMR4(n) ; FMR4(n+4)
#define FMR16(n) FMR8(n) ; FMR8(n+8)
#define FMR32(n) FMR16(n) ; FMR16(n+16)
FMR32(0)
FTR_SECTION_ELSE
/*
* To denormalise we need to move a copy of the register to itself.
* For POWER7 do that here for the first 32 VSX registers only.
*/
mfmsr r10
oris r10,r10,MSR_VSX@h
mtmsrd r10
sync
#define XVCPSGNDP2(n) XVCPSGNDP(n,n,n) ; XVCPSGNDP(n+1,n+1,n+1)
#define XVCPSGNDP4(n) XVCPSGNDP2(n) ; XVCPSGNDP2(n+2)
#define XVCPSGNDP8(n) XVCPSGNDP4(n) ; XVCPSGNDP4(n+4)
#define XVCPSGNDP16(n) XVCPSGNDP8(n) ; XVCPSGNDP8(n+8)
#define XVCPSGNDP32(n) XVCPSGNDP16(n) ; XVCPSGNDP16(n+16)
XVCPSGNDP32(0)
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
BEGIN_FTR_SECTION
b denorm_done
END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
/*
* To denormalise we need to move a copy of the register to itself.
* For POWER8 we need to do that for all 64 VSX registers
*/
XVCPSGNDP32(32)
denorm_done:
mtspr SPRN_HSRR0,r11
mtcrf 0x80,r9
ld r9,PACA_EXGEN+EX_R9(r13)
RESTORE_PPR_PACA(PACA_EXGEN, r10)
BEGIN_FTR_SECTION
ld r10,PACA_EXGEN+EX_CFAR(r13)
mtspr SPRN_CFAR,r10
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
ld r10,PACA_EXGEN+EX_R10(r13)
ld r11,PACA_EXGEN+EX_R11(r13)
ld r12,PACA_EXGEN+EX_R12(r13)
ld r13,PACA_EXGEN+EX_R13(r13)
HRFID
b .
#endif
EXC_COMMON_HV(denorm_common, 0x1500, unknown_exception)
#ifdef CONFIG_CBE_RAS
EXC_REAL_HV(cbe_maintenance, 0x1600, 0x100)
EXC_VIRT_NONE(0x5600, 0x100)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1600)
EXC_COMMON(cbe_maintenance_common, 0x1600, cbe_maintenance_exception)
#else /* CONFIG_CBE_RAS */
EXC_REAL_NONE(0x1600, 0x100)
EXC_VIRT_NONE(0x5600, 0x100)
#endif
EXC_REAL(altivec_assist, 0x1700, 0x100)
EXC_VIRT(altivec_assist, 0x5700, 0x100, 0x1700)
TRAMP_KVM(PACA_EXGEN, 0x1700)
#ifdef CONFIG_ALTIVEC
EXC_COMMON(altivec_assist_common, 0x1700, altivec_assist_exception)
#else
EXC_COMMON(altivec_assist_common, 0x1700, unknown_exception)
#endif
#ifdef CONFIG_CBE_RAS
EXC_REAL_HV(cbe_thermal, 0x1800, 0x100)
EXC_VIRT_NONE(0x5800, 0x100)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1800)
EXC_COMMON(cbe_thermal_common, 0x1800, cbe_thermal_exception)
#else /* CONFIG_CBE_RAS */
EXC_REAL_NONE(0x1800, 0x100)
EXC_VIRT_NONE(0x5800, 0x100)
#endif
#ifdef CONFIG_PPC_WATCHDOG
#define MASKED_DEC_HANDLER_LABEL 3f
#define MASKED_DEC_HANDLER(_H) \
3: /* soft-nmi */ \
std r12,PACA_EXGEN+EX_R12(r13); \
GET_SCRATCH0(r10); \
std r10,PACA_EXGEN+EX_R13(r13); \
EXCEPTION_PROLOG_PSERIES_1(soft_nmi_common, _H)
/*
* Branch to soft_nmi_interrupt using the emergency stack. The emergency
* stack is one that is usable by maskable interrupts so long as MSR_EE
* remains off. It is used for recovery when something has corrupted the
* normal kernel stack, for example. The "soft NMI" must not use the process
* stack because we want irq disabled sections to avoid touching the stack
* at all (other than PMU interrupts), so use the emergency stack for this,
* and run it entirely with interrupts hard disabled.
*/
EXC_COMMON_BEGIN(soft_nmi_common)
mr r10,r1
ld r1,PACAEMERGSP(r13)
subi r1,r1,INT_FRAME_SIZE
EXCEPTION_COMMON_NORET_STACK(PACA_EXGEN, 0x900,
system_reset, soft_nmi_interrupt,
ADD_NVGPRS;ADD_RECONCILE)
b ret_from_except
#else /* CONFIG_PPC_WATCHDOG */
#define MASKED_DEC_HANDLER_LABEL 2f /* normal return */
#define MASKED_DEC_HANDLER(_H)
#endif /* CONFIG_PPC_WATCHDOG */
/*
* An interrupt came in while soft-disabled. We set paca->irq_happened, then:
* - If it was a decrementer interrupt, we bump the dec to max and and return.
* - If it was a doorbell we return immediately since doorbells are edge
* triggered and won't automatically refire.
* - If it was a HMI we return immediately since we handled it in realmode
* and it won't refire.
* - else we hard disable and return.
* This is called with r10 containing the value to OR to the paca field.
*/
#define MASKED_INTERRUPT(_H) \
masked_##_H##interrupt: \
std r11,PACA_EXGEN+EX_R11(r13); \
lbz r11,PACAIRQHAPPENED(r13); \
or r11,r11,r10; \
stb r11,PACAIRQHAPPENED(r13); \
cmpwi r10,PACA_IRQ_DEC; \
bne 1f; \
lis r10,0x7fff; \
ori r10,r10,0xffff; \
mtspr SPRN_DEC,r10; \
b MASKED_DEC_HANDLER_LABEL; \
1: andi. r10,r10,(PACA_IRQ_DBELL|PACA_IRQ_HMI); \
bne 2f; \
mfspr r10,SPRN_##_H##SRR1; \
xori r10,r10,MSR_EE; /* clear MSR_EE */ \
mtspr SPRN_##_H##SRR1,r10; \
2: mtcrf 0x80,r9; \
ld r9,PACA_EXGEN+EX_R9(r13); \
ld r10,PACA_EXGEN+EX_R10(r13); \
ld r11,PACA_EXGEN+EX_R11(r13); \
/* returns to kernel where r13 must be set up, so don't restore it */ \
##_H##rfid; \
b .; \
MASKED_DEC_HANDLER(_H)
/*
* Real mode exceptions actually use this too, but alternate
* instruction code patches (which end up in the common .text area)
* cannot reach these if they are put there.
*/
USE_FIXED_SECTION(virt_trampolines)
MASKED_INTERRUPT()
MASKED_INTERRUPT(H)
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
TRAMP_REAL_BEGIN(kvmppc_skip_interrupt)
/*
* Here all GPRs are unchanged from when the interrupt happened
* except for r13, which is saved in SPRG_SCRATCH0.
*/
mfspr r13, SPRN_SRR0
addi r13, r13, 4
mtspr SPRN_SRR0, r13
GET_SCRATCH0(r13)
rfid
b .
TRAMP_REAL_BEGIN(kvmppc_skip_Hinterrupt)
/*
* Here all GPRs are unchanged from when the interrupt happened
* except for r13, which is saved in SPRG_SCRATCH0.
*/
mfspr r13, SPRN_HSRR0
addi r13, r13, 4
mtspr SPRN_HSRR0, r13
GET_SCRATCH0(r13)
hrfid
b .
#endif
/*
* Ensure that any handlers that get invoked from the exception prologs
* above are below the first 64KB (0x10000) of the kernel image because
* the prologs assemble the addresses of these handlers using the
* LOAD_HANDLER macro, which uses an ori instruction.
*/
/*** Common interrupt handlers ***/
/*
* Relocation-on interrupts: A subset of the interrupts can be delivered
* with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
* it. Addresses are the same as the original interrupt addresses, but
* offset by 0xc000000000004000.
* It's impossible to receive interrupts below 0x300 via this mechanism.
* KVM: None of these traps are from the guest ; anything that escalated
* to HV=1 from HV=0 is delivered via real mode handlers.
*/
/*
* This uses the standard macro, since the original 0x300 vector
* only has extra guff for STAB-based processors -- which never
* come here.
*/
EXC_COMMON_BEGIN(ppc64_runlatch_on_trampoline)
b __ppc64_runlatch_on
USE_FIXED_SECTION(virt_trampolines)
/*
* The __end_interrupts marker must be past the out-of-line (OOL)
* handlers, so that they are copied to real address 0x100 when running
* a relocatable kernel. This ensures they can be reached from the short
* trampoline handlers (like 0x4f00, 0x4f20, etc.) which branch
* directly, without using LOAD_HANDLER().
*/
.align 7
.globl __end_interrupts
__end_interrupts:
DEFINE_FIXED_SYMBOL(__end_interrupts)
#ifdef CONFIG_PPC_970_NAP
EXC_COMMON_BEGIN(power4_fixup_nap)
andc r9,r9,r10
std r9,TI_LOCAL_FLAGS(r11)
ld r10,_LINK(r1) /* make idle task do the */
std r10,_NIP(r1) /* equivalent of a blr */
blr
#endif
CLOSE_FIXED_SECTION(real_vectors);
CLOSE_FIXED_SECTION(real_trampolines);
CLOSE_FIXED_SECTION(virt_vectors);
CLOSE_FIXED_SECTION(virt_trampolines);
USE_TEXT_SECTION()
/*
* Hash table stuff
*/
.balign IFETCH_ALIGN_BYTES
do_hash_page:
#ifdef CONFIG_PPC_STD_MMU_64
lis r0,DSISR_BAD_FAULT_64S@h
ori r0,r0,DSISR_BAD_FAULT_64S@l
and. r0,r4,r0 /* weird error? */
bne- handle_page_fault /* if not, try to insert a HPTE */
CURRENT_THREAD_INFO(r11, r1)
lwz r0,TI_PREEMPT(r11) /* If we're in an "NMI" */
andis. r0,r0,NMI_MASK@h /* (i.e. an irq when soft-disabled) */
bne 77f /* then don't call hash_page now */
/*
* r3 contains the faulting address
* r4 msr
* r5 contains the trap number
* r6 contains dsisr
*
* at return r3 = 0 for success, 1 for page fault, negative for error
*/
mr r4,r12
ld r6,_DSISR(r1)
bl __hash_page /* build HPTE if possible */
cmpdi r3,0 /* see if __hash_page succeeded */
/* Success */
beq fast_exc_return_irq /* Return from exception on success */
/* Error */
blt- 13f
/* Reload DSISR into r4 for the DABR check below */
ld r4,_DSISR(r1)
#endif /* CONFIG_PPC_STD_MMU_64 */
/* Here we have a page fault that hash_page can't handle. */
handle_page_fault:
11: andis. r0,r4,DSISR_DABRMATCH@h
bne- handle_dabr_fault
ld r4,_DAR(r1)
ld r5,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_page_fault
cmpdi r3,0
beq+ 12f
bl save_nvgprs
mr r5,r3
addi r3,r1,STACK_FRAME_OVERHEAD
lwz r4,_DAR(r1)
bl bad_page_fault
b ret_from_except
/* We have a data breakpoint exception - handle it */
handle_dabr_fault:
bl save_nvgprs
ld r4,_DAR(r1)
ld r5,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_break
12: b ret_from_except_lite
#ifdef CONFIG_PPC_STD_MMU_64
/* We have a page fault that hash_page could handle but HV refused
* the PTE insertion
*/
13: bl save_nvgprs
mr r5,r3
addi r3,r1,STACK_FRAME_OVERHEAD
ld r4,_DAR(r1)
bl low_hash_fault
b ret_from_except
#endif
/*
* We come here as a result of a DSI at a point where we don't want
* to call hash_page, such as when we are accessing memory (possibly
* user memory) inside a PMU interrupt that occurred while interrupts
* were soft-disabled. We want to invoke the exception handler for
* the access, or panic if there isn't a handler.
*/
77: bl save_nvgprs
mr r4,r3
addi r3,r1,STACK_FRAME_OVERHEAD
li r5,SIGSEGV
bl bad_page_fault
b ret_from_except
/*
* Here we have detected that the kernel stack pointer is bad.
* R9 contains the saved CR, r13 points to the paca,
* r10 contains the (bad) kernel stack pointer,
* r11 and r12 contain the saved SRR0 and SRR1.
* We switch to using an emergency stack, save the registers there,
* and call kernel_bad_stack(), which panics.
*/
bad_stack:
ld r1,PACAEMERGSP(r13)
subi r1,r1,64+INT_FRAME_SIZE
std r9,_CCR(r1)
std r10,GPR1(r1)
std r11,_NIP(r1)
std r12,_MSR(r1)
mfspr r11,SPRN_DAR
mfspr r12,SPRN_DSISR
std r11,_DAR(r1)
std r12,_DSISR(r1)
mflr r10
mfctr r11
mfxer r12
std r10,_LINK(r1)
std r11,_CTR(r1)
std r12,_XER(r1)
SAVE_GPR(0,r1)
SAVE_GPR(2,r1)
ld r10,EX_R3(r3)
std r10,GPR3(r1)
SAVE_GPR(4,r1)
SAVE_4GPRS(5,r1)
ld r9,EX_R9(r3)
ld r10,EX_R10(r3)
SAVE_2GPRS(9,r1)
ld r9,EX_R11(r3)
ld r10,EX_R12(r3)
ld r11,EX_R13(r3)
std r9,GPR11(r1)
std r10,GPR12(r1)
std r11,GPR13(r1)
BEGIN_FTR_SECTION
ld r10,EX_CFAR(r3)
std r10,ORIG_GPR3(r1)
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
SAVE_8GPRS(14,r1)
SAVE_10GPRS(22,r1)
lhz r12,PACA_TRAP_SAVE(r13)
std r12,_TRAP(r1)
addi r11,r1,INT_FRAME_SIZE
std r11,0(r1)
li r12,0
std r12,0(r11)
ld r2,PACATOC(r13)
ld r11,exception_marker@toc(r2)
std r12,RESULT(r1)
std r11,STACK_FRAME_OVERHEAD-16(r1)
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl kernel_bad_stack
b 1b
_ASM_NOKPROBE_SYMBOL(bad_stack);
/*
* When doorbell is triggered from system reset wakeup, the message is
* not cleared, so it would fire again when EE is enabled.
*
* When coming from local_irq_enable, there may be the same problem if
* we were hard disabled.
*
* Execute msgclr to clear pending exceptions before handling it.
*/
h_doorbell_common_msgclr:
LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
PPC_MSGCLR(3)
b h_doorbell_common
doorbell_super_common_msgclr:
LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
PPC_MSGCLRP(3)
b doorbell_super_common
/*
* Called from arch_local_irq_enable when an interrupt needs
* to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
* which kind of interrupt. MSR:EE is already off. We generate a
* stackframe like if a real interrupt had happened.
*
* Note: While MSR:EE is off, we need to make sure that _MSR
* in the generated frame has EE set to 1 or the exception
* handler will not properly re-enable them.
*
* Note that we don't specify LR as the NIP (return address) for
* the interrupt because that would unbalance the return branch
* predictor.
*/
_GLOBAL(__replay_interrupt)
/* We are going to jump to the exception common code which
* will retrieve various register values from the PACA which
* we don't give a damn about, so we don't bother storing them.
*/
mfmsr r12
LOAD_REG_ADDR(r11, replay_interrupt_return)
mfcr r9
ori r12,r12,MSR_EE
cmpwi r3,0x900
beq decrementer_common
cmpwi r3,0x500
BEGIN_FTR_SECTION
beq h_virt_irq_common
FTR_SECTION_ELSE
beq hardware_interrupt_common
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_300)
BEGIN_FTR_SECTION
cmpwi r3,0xa00
beq h_doorbell_common_msgclr
cmpwi r3,0xe60
beq hmi_exception_common
FTR_SECTION_ELSE
cmpwi r3,0xa00
beq doorbell_super_common_msgclr
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
replay_interrupt_return:
blr
_ASM_NOKPROBE_SYMBOL(__replay_interrupt)