blob: 6b800eec31f2fe16bda42e896e30eb3a2e31e6dd [file] [log] [blame]
/*
* Machine check exception handling CPU-side for power7 and power8
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright 2013 IBM Corporation
* Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
*/
#undef DEBUG
#define pr_fmt(fmt) "mce_power: " fmt
#include <linux/types.h>
#include <linux/ptrace.h>
#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);
}
/* flush SLBs and reload */
#ifdef CONFIG_PPC_BOOK3S_64
void flush_and_reload_slb(void)
{
/* Invalidate all SLBs */
slb_flush_all_realmode();
#ifdef CONFIG_KVM_BOOK3S_HANDLER
/*
* If machine check is hit when in guest or in transition, we will
* only flush the SLBs and continue.
*/
if (get_paca()->kvm_hstate.in_guest)
return;
#endif
if (early_radix_enabled())
return;
/*
* This probably shouldn't happen, but it may be possible it's
* called in early boot before SLB shadows are allocated.
*/
if (!get_slb_shadow())
return;
slb_restore_bolted_realmode();
}
#endif
static void flush_erat(void)
{
#ifdef CONFIG_PPC_BOOK3S_64
if (!early_cpu_has_feature(CPU_FTR_ARCH_300)) {
flush_and_reload_slb();
return;
}
#endif
/* PPC_INVALIDATE_ERAT can only be used on ISA v3 and newer */
asm volatile(PPC_INVALIDATE_ERAT : : :"memory");
}
#define MCE_FLUSH_SLB 1
#define MCE_FLUSH_TLB 2
#define MCE_FLUSH_ERAT 3
static int mce_flush(int what)
{
#ifdef CONFIG_PPC_BOOK3S_64
if (what == MCE_FLUSH_SLB) {
flush_and_reload_slb();
return 1;
}
#endif
if (what == MCE_FLUSH_ERAT) {
flush_erat();
return 1;
}
if (what == MCE_FLUSH_TLB) {
tlbiel_all();
return 1;
}
return 0;
}
#define SRR1_MC_LOADSTORE(srr1) ((srr1) & PPC_BIT(42))
struct mce_ierror_table {
unsigned long srr1_mask;
unsigned long srr1_value;
bool nip_valid; /* nip is a valid indicator of faulting address */
unsigned int error_type;
unsigned int error_subtype;
unsigned int initiator;
unsigned int severity;
};
static const struct mce_ierror_table mce_p7_ierror_table[] = {
{ 0x00000000001c0000, 0x0000000000040000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000080000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x00000000000c0000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000100000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000140000, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x0000000000180000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000001c0000, 0x00000000001c0000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0, 0, 0, 0, 0, 0 } };
static const struct mce_ierror_table mce_p8_ierror_table[] = {
{ 0x00000000081c0000, 0x0000000000040000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000080000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000000c0000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000100000, true,
MCE_ERROR_TYPE_ERAT,MCE_ERAT_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000140000, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000180000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000001c0000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008000000, true,
MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_IFETCH_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008040000, true,
MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_PAGE_TABLE_WALK_IFETCH_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0, 0, 0, 0, 0, 0 } };
static const struct mce_ierror_table mce_p9_ierror_table[] = {
{ 0x00000000081c0000, 0x0000000000040000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000080000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000000c0000, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000100000, true,
MCE_ERROR_TYPE_ERAT,MCE_ERAT_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000140000, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000000180000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000001c0000, true,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_IFETCH_FOREIGN,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008000000, true,
MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_IFETCH_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008040000, true,
MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_PAGE_TABLE_WALK_IFETCH_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x00000000080c0000, true,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008100000, true,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000000081c0000, 0x0000000008140000, false,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_STORE,
MCE_INITIATOR_CPU, MCE_SEV_FATAL, }, /* ASYNC is fatal */
{ 0x00000000081c0000, 0x0000000008180000, false,
MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_STORE_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_FATAL, }, /* ASYNC is fatal */
{ 0x00000000081c0000, 0x00000000081c0000, true,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH_FOREIGN,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0, 0, 0, 0, 0, 0 } };
struct mce_derror_table {
unsigned long dsisr_value;
bool dar_valid; /* dar is a valid indicator of faulting address */
unsigned int error_type;
unsigned int error_subtype;
unsigned int initiator;
unsigned int severity;
};
static const struct mce_derror_table mce_p7_derror_table[] = {
{ 0x00008000, false,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00004000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000800, true,
MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000400, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, /* Before PARITY */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000040, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0, false, 0, 0, 0, 0 } };
static const struct mce_derror_table mce_p8_derror_table[] = {
{ 0x00008000, false,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00004000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00002000, true,
MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00001000, true,
MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000800, true,
MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000400, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000200, true,
MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, /* SECONDARY ERAT */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, /* Before PARITY */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0, false, 0, 0, 0, 0 } };
static const struct mce_derror_table mce_p9_derror_table[] = {
{ 0x00008000, false,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00004000, true,
MCE_ERROR_TYPE_UE, MCE_UE_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00002000, true,
MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_LOAD_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00001000, true,
MCE_ERROR_TYPE_LINK, MCE_LINK_ERROR_PAGE_TABLE_WALK_LOAD_STORE_TIMEOUT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000800, true,
MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000400, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000200, false,
MCE_ERROR_TYPE_USER, MCE_USER_ERROR_TLBIE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, /* Before PARITY */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000040, true,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_LOAD,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000020, false,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000010, false,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000008, false,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_LOAD_STORE_FOREIGN,
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,
uint64_t *phys_addr)
{
uint64_t srr1 = regs->msr;
int handled = 0;
int i;
*addr = 0;
for (i = 0; table[i].srr1_mask; i++) {
if ((srr1 & table[i].srr1_mask) != table[i].srr1_value)
continue;
/* attempt to correct the error */
switch (table[i].error_type) {
case MCE_ERROR_TYPE_SLB:
handled = mce_flush(MCE_FLUSH_SLB);
break;
case MCE_ERROR_TYPE_ERAT:
handled = mce_flush(MCE_FLUSH_ERAT);
break;
case MCE_ERROR_TYPE_TLB:
handled = mce_flush(MCE_FLUSH_TLB);
break;
}
/* now fill in mce_error_info */
mce_err->error_type = table[i].error_type;
switch (table[i].error_type) {
case MCE_ERROR_TYPE_UE:
mce_err->u.ue_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_SLB:
mce_err->u.slb_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_ERAT:
mce_err->u.erat_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_TLB:
mce_err->u.tlb_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_USER:
mce_err->u.user_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_RA:
mce_err->u.ra_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_LINK:
mce_err->u.link_error_type = table[i].error_subtype;
break;
}
mce_err->severity = table[i].severity;
mce_err->initiator = table[i].initiator;
if (table[i].nip_valid) {
*addr = regs->nip;
if (mce_err->severity == MCE_SEV_ERROR_SYNC &&
table[i].error_type == MCE_ERROR_TYPE_UE) {
unsigned long pfn;
if (get_paca()->in_mce < MAX_MCE_DEPTH) {
pfn = addr_to_pfn(regs, regs->nip);
if (pfn != ULONG_MAX) {
*phys_addr =
(pfn << PAGE_SHIFT);
}
}
}
}
return handled;
}
mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
mce_err->severity = MCE_SEV_ERROR_SYNC;
mce_err->initiator = MCE_INITIATOR_CPU;
return 0;
}
static int mce_handle_derror(struct pt_regs *regs,
const struct mce_derror_table table[],
struct mce_error_info *mce_err, uint64_t *addr,
uint64_t *phys_addr)
{
uint64_t dsisr = regs->dsisr;
int handled = 0;
int found = 0;
int i;
*addr = 0;
for (i = 0; table[i].dsisr_value; i++) {
if (!(dsisr & table[i].dsisr_value))
continue;
/* attempt to correct the error */
switch (table[i].error_type) {
case MCE_ERROR_TYPE_SLB:
if (mce_flush(MCE_FLUSH_SLB))
handled = 1;
break;
case MCE_ERROR_TYPE_ERAT:
if (mce_flush(MCE_FLUSH_ERAT))
handled = 1;
break;
case MCE_ERROR_TYPE_TLB:
if (mce_flush(MCE_FLUSH_TLB))
handled = 1;
break;
}
/*
* Attempt to handle multiple conditions, but only return
* one. Ensure uncorrectable errors are first in the table
* to match.
*/
if (found)
continue;
/* now fill in mce_error_info */
mce_err->error_type = table[i].error_type;
switch (table[i].error_type) {
case MCE_ERROR_TYPE_UE:
mce_err->u.ue_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_SLB:
mce_err->u.slb_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_ERAT:
mce_err->u.erat_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_TLB:
mce_err->u.tlb_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_USER:
mce_err->u.user_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_RA:
mce_err->u.ra_error_type = table[i].error_subtype;
break;
case MCE_ERROR_TYPE_LINK:
mce_err->u.link_error_type = table[i].error_subtype;
break;
}
mce_err->severity = table[i].severity;
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)
mce_find_instr_ea_and_pfn(regs, addr, phys_addr);
}
found = 1;
}
if (found)
return handled;
mce_err->error_type = MCE_ERROR_TYPE_UNKNOWN;
mce_err->severity = MCE_SEV_ERROR_SYNC;
mce_err->initiator = MCE_INITIATOR_CPU;
return 0;
}
static long mce_handle_ue_error(struct pt_regs *regs)
{
long handled = 0;
/*
* On specific SCOM read via MMIO we may get a machine check
* exception with SRR0 pointing inside opal. If that is the
* case OPAL may have recovery address to re-read SCOM data in
* different way and hence we can recover from this MC.
*/
if (ppc_md.mce_check_early_recovery) {
if (ppc_md.mce_check_early_recovery(regs))
handled = 1;
}
return handled;
}
static long mce_handle_error(struct pt_regs *regs,
const struct mce_derror_table dtable[],
const struct mce_ierror_table itable[])
{
struct mce_error_info mce_err = { 0 };
uint64_t addr, phys_addr = ULONG_MAX;
uint64_t srr1 = regs->msr;
long handled;
if (SRR1_MC_LOADSTORE(srr1))
handled = mce_handle_derror(regs, dtable, &mce_err, &addr,
&phys_addr);
else
handled = mce_handle_ierror(regs, itable, &mce_err, &addr,
&phys_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, phys_addr);
return handled;
}
long __machine_check_early_realmode_p7(struct pt_regs *regs)
{
/* P7 DD1 leaves top bits of DSISR undefined */
regs->dsisr &= 0x0000ffff;
return mce_handle_error(regs, mce_p7_derror_table, mce_p7_ierror_table);
}
long __machine_check_early_realmode_p8(struct pt_regs *regs)
{
return mce_handle_error(regs, mce_p8_derror_table, mce_p8_ierror_table);
}
long __machine_check_early_realmode_p9(struct pt_regs *regs)
{
/*
* On POWER9 DD2.1 and below, it's possible to get a machine check
* caused by a paste instruction where only DSISR bit 25 is set. This
* will result in the MCE handler seeing an unknown event and the kernel
* crashing. An MCE that occurs like this is spurious, so we don't need
* to do anything in terms of servicing it. If there is something that
* needs to be serviced, the CPU will raise the MCE again with the
* correct DSISR so that it can be serviced properly. So detect this
* case and mark it as handled.
*/
if (SRR1_MC_LOADSTORE(regs->msr) && regs->dsisr == 0x02000000)
return 1;
return mce_handle_error(regs, mce_p9_derror_table, mce_p9_ierror_table);
}