diff options
| -rw-r--r-- | arch/powerpc/include/asm/bug.h | 1 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/fadump.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/kernel/fadump.c | 9 | ||||
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 22 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal.c | 32 |
5 files changed, 59 insertions, 7 deletions
diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h index 87fcc1948817..7ee763d3bea9 100644 --- a/arch/powerpc/include/asm/bug.h +++ b/arch/powerpc/include/asm/bug.h @@ -133,6 +133,7 @@ extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long); extern void bad_page_fault(struct pt_regs *, unsigned long, int); extern void _exception(int, struct pt_regs *, int, unsigned long); extern void die(const char *, struct pt_regs *, long); +extern bool die_will_crash(void); #endif /* !__ASSEMBLY__ */ diff --git a/arch/powerpc/include/asm/fadump.h b/arch/powerpc/include/asm/fadump.h index ce88bbe1d809..5a23010af600 100644 --- a/arch/powerpc/include/asm/fadump.h +++ b/arch/powerpc/include/asm/fadump.h @@ -209,11 +209,13 @@ extern int early_init_dt_scan_fw_dump(unsigned long node, extern int fadump_reserve_mem(void); extern int setup_fadump(void); extern int is_fadump_active(void); +extern int should_fadump_crash(void); extern void crash_fadump(struct pt_regs *, const char *); extern void fadump_cleanup(void); #else /* CONFIG_FA_DUMP */ static inline int is_fadump_active(void) { return 0; } +static inline int should_fadump_crash(void) { return 0; } static inline void crash_fadump(struct pt_regs *regs, const char *str) { } #endif #endif diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index dd2c85f0bd8d..e1431800bfb9 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -125,6 +125,13 @@ int is_fadump_boot_memory_area(u64 addr, ulong size) return (addr + size) > RMA_START && addr <= fw_dump.boot_memory_size; } +int should_fadump_crash(void) +{ + if (!fw_dump.dump_registered || !fw_dump.fadumphdr_addr) + return 0; + return 1; +} + int is_fadump_active(void) { return fw_dump.dump_active; @@ -518,7 +525,7 @@ void crash_fadump(struct pt_regs *regs, const char *str) struct fadump_crash_info_header *fdh = NULL; int old_cpu, this_cpu; - if (!fw_dump.dump_registered || !fw_dump.fadumphdr_addr) + if (!should_fadump_crash()) return; /* diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 5e4db2fc2add..6858d910b47e 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -114,6 +114,28 @@ static void pmac_backlight_unblank(void) static inline void pmac_backlight_unblank(void) { } #endif +/* + * If oops/die is expected to crash the machine, return true here. + * + * This should not be expected to be 100% accurate, there may be + * notifiers registered or other unexpected conditions that may bring + * down the kernel. Or if the current process in the kernel is holding + * locks or has other critical state, the kernel may become effectively + * unusable anyway. + */ +bool die_will_crash(void) +{ + if (should_fadump_crash()) + return true; + if (kexec_should_crash(current)) + return true; + if (in_interrupt() || panic_on_oops || + !current->pid || is_global_init(current)) + return true; + + return false; +} + static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED; static int die_owner = -1; static unsigned int die_nest_count; diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index d246f919cba2..65c79ecf5a4d 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -36,6 +36,7 @@ #include <asm/firmware.h> #include <asm/mce.h> #include <asm/imc-pmu.h> +#include <asm/bug.h> #include "powernv.h" @@ -425,17 +426,36 @@ static int opal_recover_mce(struct pt_regs *regs, /* Fatal machine check */ pr_err("Machine check interrupt is fatal\n"); recovered = 0; - } else if ((evt->severity == MCE_SEV_ERROR_SYNC) && - (user_mode(regs) && !is_global_init(current))) { + } + + if (!recovered && evt->severity == MCE_SEV_ERROR_SYNC) { /* - * For now, kill the task if we have received exception when - * in userspace. + * Try to kill processes if we get a synchronous machine check + * (e.g., one caused by execution of this instruction). This + * will devolve into a panic if we try to kill init or are in + * an interrupt etc. * * TODO: Queue up this address for hwpoisioning later. + * TODO: This is not quite right for d-side machine + * checks ->nip is not necessarily the important + * address. */ - _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip); - recovered = 1; + if ((user_mode(regs))) { + _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip); + recovered = 1; + } else if (die_will_crash()) { + /* + * die() would kill the kernel, so better to go via + * the platform reboot code that will log the + * machine check. + */ + recovered = 0; + } else { + die("Machine check", regs, SIGBUS); + recovered = 1; + } } + return recovered; } |