diff options
| -rw-r--r-- | arch/powerpc/include/asm/exception-64s.h | 5 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/mce.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 2 | ||||
| -rw-r--r-- | arch/powerpc/kernel/mce.c | 6 | ||||
| -rw-r--r-- | arch/powerpc/kernel/mce_power.c | 87 |
5 files changed, 94 insertions, 8 deletions
diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index 9a318973af05..b27205297e1d 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -55,6 +55,11 @@ #endif /* + * maximum recursive depth of MCE exceptions + */ +#define MAX_MCE_DEPTH 4 + +/* * EX_LR is only used in EXSLB and where it does not overlap with EX_DAR * EX_CCR similarly with DSISR, but being 4 byte registers there is a hole * in the save area so it's not necessary to overlap them. Could be used diff --git a/arch/powerpc/include/asm/mce.h b/arch/powerpc/include/asm/mce.h index 75292c7eee48..3a1226e9b465 100644 --- a/arch/powerpc/include/asm/mce.h +++ b/arch/powerpc/include/asm/mce.h @@ -204,7 +204,7 @@ struct mce_error_info { extern void save_mce_event(struct pt_regs *regs, long handled, struct mce_error_info *mce_err, uint64_t nip, - uint64_t addr); + uint64_t addr, uint64_t phys_addr); extern int get_mce_event(struct machine_check_event *mce, bool release); extern void release_mce_event(void); extern void machine_check_queue_event(void); diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 8c32dd4cac20..ce04b1c2ac8e 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -232,7 +232,7 @@ BEGIN_FTR_SECTION 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 + cmpwi r10,MAX_MCE_DEPTH 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 */ diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c index d1775bdade72..1af7c559edbc 100644 --- a/arch/powerpc/kernel/mce.c +++ b/arch/powerpc/kernel/mce.c @@ -82,7 +82,7 @@ static void mce_set_error_info(struct machine_check_event *mce, */ void save_mce_event(struct pt_regs *regs, long handled, struct mce_error_info *mce_err, - uint64_t nip, uint64_t addr) + uint64_t nip, uint64_t addr, uint64_t phys_addr) { int index = __this_cpu_inc_return(mce_nest_count) - 1; struct machine_check_event *mce = this_cpu_ptr(&mce_event[index]); @@ -140,6 +140,10 @@ void save_mce_event(struct pt_regs *regs, long handled, } else if (mce->error_type == MCE_ERROR_TYPE_UE) { mce->u.ue_error.effective_address_provided = true; mce->u.ue_error.effective_address = addr; + if (phys_addr != ULONG_MAX) { + mce->u.ue_error.physical_address_provided = true; + mce->u.ue_error.physical_address = phys_addr; + } } return; } diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c index d37e612050b5..e61b80e37e1f 100644 --- a/arch/powerpc/kernel/mce_power.c +++ b/arch/powerpc/kernel/mce_power.c @@ -27,6 +27,36 @@ #include <asm/mmu.h> #include <asm/mce.h> #include <asm/machdep.h> +#include <asm/pgtable.h> +#include <asm/pte-walk.h> +#include <asm/sstep.h> +#include <asm/exception-64s.h> + +/* + * Convert an address related to an mm to a PFN. NOTE: we are in real + * mode, we could potentially race with page table updates. + */ +static unsigned long addr_to_pfn(struct pt_regs *regs, unsigned long addr) +{ + pte_t *ptep; + unsigned long flags; + struct mm_struct *mm; + + if (user_mode(regs)) + mm = current->mm; + else + mm = &init_mm; + + local_irq_save(flags); + if (mm == current->mm) + ptep = find_current_mm_pte(mm->pgd, addr, NULL, NULL); + else + ptep = find_init_mm_pte(addr, NULL); + local_irq_restore(flags); + if (!ptep || pte_special(*ptep)) + return ULONG_MAX; + return pte_pfn(*ptep); +} static void flush_tlb_206(unsigned int num_sets, unsigned int action) { @@ -421,6 +451,41 @@ static const struct mce_derror_table mce_p9_derror_table[] = { MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, }, { 0, false, 0, 0, 0, 0 } }; +static int mce_find_instr_ea_and_pfn(struct pt_regs *regs, uint64_t *addr, + uint64_t *phys_addr) +{ + /* + * Carefully look at the NIP to determine + * the instruction to analyse. Reading the NIP + * in real-mode is tricky and can lead to recursive + * faults + */ + int instr; + unsigned long pfn, instr_addr; + struct instruction_op op; + struct pt_regs tmp = *regs; + + pfn = addr_to_pfn(regs, regs->nip); + if (pfn != ULONG_MAX) { + instr_addr = (pfn << PAGE_SHIFT) + (regs->nip & ~PAGE_MASK); + instr = *(unsigned int *)(instr_addr); + if (!analyse_instr(&op, &tmp, instr)) { + pfn = addr_to_pfn(regs, op.ea); + *addr = op.ea; + *phys_addr = (pfn << PAGE_SHIFT); + return 0; + } + /* + * analyse_instr() might fail if the instruction + * is not a load/store, although this is unexpected + * for load/store errors or if we got the NIP + * wrong + */ + } + *addr = 0; + return -1; +} + static int mce_handle_ierror(struct pt_regs *regs, const struct mce_ierror_table table[], struct mce_error_info *mce_err, uint64_t *addr) @@ -489,7 +554,8 @@ static int mce_handle_ierror(struct pt_regs *regs, static int mce_handle_derror(struct pt_regs *regs, const struct mce_derror_table table[], - struct mce_error_info *mce_err, uint64_t *addr) + struct mce_error_info *mce_err, uint64_t *addr, + uint64_t *phys_addr) { uint64_t dsisr = regs->dsisr; int handled = 0; @@ -555,7 +621,17 @@ static int mce_handle_derror(struct pt_regs *regs, mce_err->initiator = table[i].initiator; if (table[i].dar_valid) *addr = regs->dar; - + else if (mce_err->severity == MCE_SEV_ERROR_SYNC && + table[i].error_type == MCE_ERROR_TYPE_UE) { + /* + * We do a maximum of 4 nested MCE calls, see + * kernel/exception-64s.h + */ + if (get_paca()->in_mce < MAX_MCE_DEPTH) + if (!mce_find_instr_ea_and_pfn(regs, addr, + phys_addr)) + handled = 1; + } found = 1; } @@ -592,19 +668,20 @@ static long mce_handle_error(struct pt_regs *regs, const struct mce_ierror_table itable[]) { struct mce_error_info mce_err = { 0 }; - uint64_t addr; + uint64_t addr, phys_addr; uint64_t srr1 = regs->msr; long handled; if (SRR1_MC_LOADSTORE(srr1)) - handled = mce_handle_derror(regs, dtable, &mce_err, &addr); + handled = mce_handle_derror(regs, dtable, &mce_err, &addr, + &phys_addr); else handled = mce_handle_ierror(regs, itable, &mce_err, &addr); if (!handled && mce_err.error_type == MCE_ERROR_TYPE_UE) handled = mce_handle_ue_error(regs); - save_mce_event(regs, handled, &mce_err, regs->nip, addr); + save_mce_event(regs, handled, &mce_err, regs->nip, addr, phys_addr); return handled; } |