diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mce/severity.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mce/severity.c | 195 |
1 files changed, 98 insertions, 97 deletions
diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c index 17e631443116..2235a7477436 100644 --- a/arch/x86/kernel/cpu/mce/severity.c +++ b/arch/x86/kernel/cpu/mce/severity.c @@ -12,7 +12,7 @@ #include <linux/uaccess.h> #include <asm/mce.h> -#include <asm/intel-family.h> +#include <asm/cpu_device_id.h> #include <asm/traps.h> #include <asm/insn.h> #include <asm/insn-eval.h> @@ -39,20 +39,20 @@ static struct severity { u64 mask; u64 result; unsigned char sev; - unsigned char mcgmask; - unsigned char mcgres; + unsigned short mcgmask; + unsigned short mcgres; unsigned char ser; unsigned char context; unsigned char excp; unsigned char covered; - unsigned char cpu_model; + unsigned int cpu_vfm; unsigned char cpu_minstepping; unsigned char bank_lo, bank_hi; char *msg; } severities[] = { #define MCESEV(s, m, c...) { .sev = MCE_ ## s ## _SEVERITY, .msg = m, ## c } #define BANK_RANGE(l, h) .bank_lo = l, .bank_hi = h -#define MODEL_STEPPING(m, s) .cpu_model = m, .cpu_minstepping = s +#define VFM_STEPPING(m, s) .cpu_vfm = m, .cpu_minstepping = s #define KERNEL .context = IN_KERNEL #define USER .context = IN_USER #define KERNEL_RECOV .context = IN_KERNEL_RECOV @@ -128,7 +128,7 @@ static struct severity { MCESEV( AO, "Uncorrected Patrol Scrub Error", SER, MASK(MCI_STATUS_UC|MCI_ADDR|0xffffeff0, MCI_ADDR|0x001000c0), - MODEL_STEPPING(INTEL_FAM6_SKYLAKE_X, 4), BANK_RANGE(13, 18) + VFM_STEPPING(INTEL_SKYLAKE_X, 4), BANK_RANGE(13, 18) ), /* ignore OVER for UCNA */ @@ -174,6 +174,18 @@ static struct severity { USER ), MCESEV( + AR, "Data load error in SEAM non-root mode", + SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA), + MCGMASK(MCG_STATUS_SEAM_NR, MCG_STATUS_SEAM_NR), + KERNEL + ), + MCESEV( + AR, "Instruction fetch error in SEAM non-root mode", + SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_INSTR), + MCGMASK(MCG_STATUS_SEAM_NR, MCG_STATUS_SEAM_NR), + KERNEL + ), + MCESEV( PANIC, "Data load in unrecoverable area of kernel", SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA), KERNEL @@ -203,6 +215,11 @@ static struct severity { BITSET(MCI_STATUS_OVER|MCI_STATUS_UC) ), MCESEV( + PANIC, "Uncorrected in kernel", + BITSET(MCI_STATUS_UC), + KERNEL + ), + MCESEV( UC, "Uncorrected", BITSET(MCI_STATUS_UC) ), @@ -222,6 +239,9 @@ static bool is_copy_from_user(struct pt_regs *regs) struct insn insn; int ret; + if (!regs) + return false; + if (copy_from_kernel_nofault(insn_buf, (void *)regs->ip, MAX_INSN_SIZE)) return false; @@ -263,115 +283,101 @@ static bool is_copy_from_user(struct pt_regs *regs) * distinguish an exception taken in user from from one * taken in the kernel. */ -static int error_context(struct mce *m, struct pt_regs *regs) +static noinstr int error_context(struct mce *m, struct pt_regs *regs) { - enum handler_type t; + int fixup_type; + bool copy_user; if ((m->cs & 3) == 3) return IN_USER; + if (!mc_recoverable(m->mcgstatus)) return IN_KERNEL; - t = ex_get_fault_handler_type(m->ip); - if (t == EX_HANDLER_FAULT) { - m->kflags |= MCE_IN_KERNEL_RECOV; + /* Allow instrumentation around external facilities usage. */ + instrumentation_begin(); + fixup_type = ex_get_fixup_type(m->ip); + copy_user = is_copy_from_user(regs); + instrumentation_end(); + + if (copy_user) { + m->kflags |= MCE_IN_KERNEL_COPYIN | MCE_IN_KERNEL_RECOV; return IN_KERNEL_RECOV; } - if (t == EX_HANDLER_UACCESS && regs && is_copy_from_user(regs)) { + + switch (fixup_type) { + case EX_TYPE_FAULT_MCE_SAFE: + case EX_TYPE_DEFAULT_MCE_SAFE: m->kflags |= MCE_IN_KERNEL_RECOV; - m->kflags |= MCE_IN_KERNEL_COPYIN; return IN_KERNEL_RECOV; - } - return IN_KERNEL; + default: + return IN_KERNEL; + } } -static int mce_severity_amd_smca(struct mce *m, enum context err_ctx) +/* See AMD PPR(s) section Machine Check Error Handling. */ +static noinstr int mce_severity_amd(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp) { - u32 addr = MSR_AMD64_SMCA_MCx_CONFIG(m->bank); - u32 low, high; + char *panic_msg = NULL; + int ret; /* - * We need to look at the following bits: - * - "succor" bit (data poisoning support), and - * - TCC bit (Task Context Corrupt) - * in MCi_STATUS to determine error severity. + * Default return value: Action required, the error must be handled + * immediately. */ - if (!mce_flags.succor) - return MCE_PANIC_SEVERITY; - - if (rdmsr_safe(addr, &low, &high)) - return MCE_PANIC_SEVERITY; - - /* TCC (Task context corrupt). If set and if IN_KERNEL, panic. */ - if ((low & MCI_CONFIG_MCAX) && - (m->status & MCI_STATUS_TCC) && - (err_ctx == IN_KERNEL)) - return MCE_PANIC_SEVERITY; - - /* ...otherwise invoke hwpoison handler. */ - return MCE_AR_SEVERITY; -} - -/* - * See AMD Error Scope Hierarchy table in a newer BKDG. For example - * 49125_15h_Models_30h-3Fh_BKDG.pdf, section "RAS Features" - */ -static int mce_severity_amd(struct mce *m, struct pt_regs *regs, int tolerant, - char **msg, bool is_excp) -{ - enum context ctx = error_context(m, regs); + ret = MCE_AR_SEVERITY; /* Processor Context Corrupt, no need to fumble too much, die! */ - if (m->status & MCI_STATUS_PCC) - return MCE_PANIC_SEVERITY; - - if (m->status & MCI_STATUS_UC) { - - if (ctx == IN_KERNEL) - return MCE_PANIC_SEVERITY; - - /* - * On older systems where overflow_recov flag is not present, we - * should simply panic if an error overflow occurs. If - * overflow_recov flag is present and set, then software can try - * to at least kill process to prolong system operation. - */ - if (mce_flags.overflow_recov) { - if (mce_flags.smca) - return mce_severity_amd_smca(m, ctx); - - /* kill current process */ - return MCE_AR_SEVERITY; - } else { - /* at least one error was not logged */ - if (m->status & MCI_STATUS_OVER) - return MCE_PANIC_SEVERITY; - } - - /* - * For any other case, return MCE_UC_SEVERITY so that we log the - * error and exit #MC handler. - */ - return MCE_UC_SEVERITY; + if (m->status & MCI_STATUS_PCC) { + panic_msg = "Processor Context Corrupt"; + ret = MCE_PANIC_SEVERITY; + goto out; + } + + if (m->status & MCI_STATUS_DEFERRED) { + ret = MCE_DEFERRED_SEVERITY; + goto out; } /* - * deferred error: poll handler catches these and adds to mce_ring so - * memory-failure can take recovery actions. + * If the UC bit is not set, the system either corrected or deferred + * the error. No action will be required after logging the error. */ - if (m->status & MCI_STATUS_DEFERRED) - return MCE_DEFERRED_SEVERITY; + if (!(m->status & MCI_STATUS_UC)) { + ret = MCE_KEEP_SEVERITY; + goto out; + } /* - * corrected error: poll handler catches these and passes responsibility - * of decoding the error to EDAC + * On MCA overflow, without the MCA overflow recovery feature the + * system will not be able to recover, panic. */ - return MCE_KEEP_SEVERITY; + if ((m->status & MCI_STATUS_OVER) && !mce_flags.overflow_recov) { + panic_msg = "Overflowed uncorrected error without MCA Overflow Recovery"; + ret = MCE_PANIC_SEVERITY; + goto out; + } + + if (!mce_flags.succor) { + panic_msg = "Uncorrected error without MCA Recovery"; + ret = MCE_PANIC_SEVERITY; + goto out; + } + + if (error_context(m, regs) == IN_KERNEL) { + panic_msg = "Uncorrected unrecoverable error in kernel context"; + ret = MCE_PANIC_SEVERITY; + } + +out: + if (msg && panic_msg) + *msg = panic_msg; + + return ret; } -static int mce_severity_intel(struct mce *m, struct pt_regs *regs, - int tolerant, char **msg, bool is_excp) +static noinstr int mce_severity_intel(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp) { enum exception excp = (is_excp ? EXCP_CONTEXT : NO_EXCP); enum context ctx = error_context(m, regs); @@ -390,7 +396,7 @@ static int mce_severity_intel(struct mce *m, struct pt_regs *regs, continue; if (s->excp && excp != s->excp) continue; - if (s->cpu_model && boot_cpu_data.x86_model != s->cpu_model) + if (s->cpu_vfm && boot_cpu_data.x86_vfm != s->cpu_vfm) continue; if (s->cpu_minstepping && boot_cpu_data.x86_stepping < s->cpu_minstepping) continue; @@ -399,23 +405,18 @@ static int mce_severity_intel(struct mce *m, struct pt_regs *regs, if (msg) *msg = s->msg; s->covered = 1; - if (s->sev >= MCE_UC_SEVERITY && ctx == IN_KERNEL) { - if (tolerant < 1) - return MCE_PANIC_SEVERITY; - } + return s->sev; } } -/* Default to mce_severity_intel */ -int (*mce_severity)(struct mce *m, struct pt_regs *regs, int tolerant, char **msg, bool is_excp) = - mce_severity_intel; - -void __init mcheck_vendor_init_severity(void) +int noinstr mce_severity(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp) { if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD || boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) - mce_severity = mce_severity_amd; + return mce_severity_amd(m, regs, msg, is_excp); + else + return mce_severity_intel(m, regs, msg, is_excp); } #ifdef CONFIG_DEBUG_FS |