diff options
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce.c | 75 |
1 files changed, 64 insertions, 11 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 9c7419e459d..54bd1b2fb4c 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -204,6 +204,9 @@ static void print_mce_tail(void) static atomic_t mce_paniced; +static int fake_panic; +static atomic_t mce_fake_paniced; + /* Panic in progress. Enable interrupts and wait for final IPI */ static void wait_for_panic(void) { @@ -221,15 +224,21 @@ static void mce_panic(char *msg, struct mce *final, char *exp) { int i; - /* - * Make sure only one CPU runs in machine check panic - */ - if (atomic_inc_return(&mce_paniced) > 1) - wait_for_panic(); - barrier(); + if (!fake_panic) { + /* + * Make sure only one CPU runs in machine check panic + */ + if (atomic_inc_return(&mce_paniced) > 1) + wait_for_panic(); + barrier(); - bust_spinlocks(1); - console_verbose(); + bust_spinlocks(1); + console_verbose(); + } else { + /* Don't log too much for fake panic */ + if (atomic_inc_return(&mce_fake_paniced) > 1) + return; + } print_mce_head(); /* First print corrected ones that are still unlogged */ for (i = 0; i < MCE_LOG_LEN; i++) { @@ -256,9 +265,12 @@ static void mce_panic(char *msg, struct mce *final, char *exp) print_mce_tail(); if (exp) printk(KERN_EMERG "Machine check: %s\n", exp); - if (panic_timeout == 0) - panic_timeout = mce_panic_timeout; - panic(msg); + if (!fake_panic) { + if (panic_timeout == 0) + panic_timeout = mce_panic_timeout; + panic(msg); + } else + printk(KERN_EMERG "Fake kernel panic: %s\n", msg); } /* Support code for software error injection */ @@ -2015,4 +2027,45 @@ struct dentry *mce_get_debugfs_dir(void) return dmce; } + +static void mce_reset(void) +{ + cpu_missing = 0; + atomic_set(&mce_fake_paniced, 0); + atomic_set(&mce_executing, 0); + atomic_set(&mce_callin, 0); + atomic_set(&global_nwo, 0); +} + +static int fake_panic_get(void *data, u64 *val) +{ + *val = fake_panic; + return 0; +} + +static int fake_panic_set(void *data, u64 val) +{ + mce_reset(); + fake_panic = val; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fake_panic_fops, fake_panic_get, + fake_panic_set, "%llu\n"); + +static int __init mce_debugfs_init(void) +{ + struct dentry *dmce, *ffake_panic; + + dmce = mce_get_debugfs_dir(); + if (!dmce) + return -ENOMEM; + ffake_panic = debugfs_create_file("fake_panic", 0444, dmce, NULL, + &fake_panic_fops); + if (!ffake_panic) + return -ENOMEM; + + return 0; +} +late_initcall(mce_debugfs_init); #endif |