diff options
| -rw-r--r-- | Documentation/x86_64/boot-options.txt | 5 | ||||
| -rw-r--r-- | arch/x86_64/kernel/mce.c | 16 |
2 files changed, 17 insertions, 4 deletions
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt index 476c0c22fbb..678e8f192db 100644 --- a/Documentation/x86_64/boot-options.txt +++ b/Documentation/x86_64/boot-options.txt @@ -6,6 +6,11 @@ only the AMD64 specific ones are listed here. Machine check mce=off disable machine check + mce=bootlog Enable logging of machine checks left over from booting. + Disabled by default because some BIOS leave bogus ones. + If your BIOS doesn't do that it's a good idea to enable though + to make sure you log even machine check events that result + in a reboot. nomce (for compatibility with i386): same as mce=off diff --git a/arch/x86_64/kernel/mce.c b/arch/x86_64/kernel/mce.c index 3b267c91bb0..8aa56736cde 100644 --- a/arch/x86_64/kernel/mce.c +++ b/arch/x86_64/kernel/mce.c @@ -36,6 +36,7 @@ static unsigned long bank[NR_BANKS] = { [0 ... NR_BANKS-1] = ~0UL }; static unsigned long console_logged; static int notify_user; static int rip_msr; +static int mce_bootlog; /* * Lockless MCE logging infrastructure. @@ -197,10 +198,11 @@ void do_machine_check(struct pt_regs * regs, long error_code) rdmsrl(MSR_IA32_MC0_ADDR + i*4, m.addr); mce_get_rip(&m, regs); - if (error_code != -1) + if (error_code >= 0) rdtscll(m.tsc); wrmsrl(MSR_IA32_MC0_STATUS + i*4, 0); - mce_log(&m); + if (error_code != -2) + mce_log(&m); /* Did this bank cause the exception? */ /* Assume that the bank with uncorrectable errors did it, @@ -315,7 +317,7 @@ static void mce_init(void *dummy) /* Log the machine checks left over from the previous reset. This also clears all registers */ - do_machine_check(NULL, -1); + do_machine_check(NULL, mce_bootlog ? -1 : -2); set_in_cr4(X86_CR4_MCE); @@ -476,11 +478,17 @@ static int __init mcheck_disable(char *str) } /* mce=off disables machine check. Note you can reenable it later - using sysfs */ + using sysfs. + mce=bootlog Log MCEs from before booting. Disabled by default to work + around buggy BIOS that leave bogus MCEs. */ static int __init mcheck_enable(char *str) { + if (*str == '=') + str++; if (!strcmp(str, "off")) mce_dont_init = 1; + else if (!strcmp(str, "bootlog")) + mce_bootlog = 1; else printk("mce= argument %s ignored. Please use /sys", str); return 0; |