diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mce/core.c')
-rw-r--r-- | arch/x86/kernel/cpu/mce/core.c | 65 |
1 files changed, 37 insertions, 28 deletions
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 54165f3569e8..e9265e2f28c9 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -42,6 +42,8 @@ #include <linux/export.h> #include <linux/jump_label.h> #include <linux/set_memory.h> +#include <linux/task_work.h> +#include <linux/hardirq.h> #include <asm/intel-family.h> #include <asm/processor.h> @@ -1086,23 +1088,6 @@ static void mce_clear_state(unsigned long *toclear) } } -static int do_memory_failure(struct mce *m) -{ - int flags = MF_ACTION_REQUIRED; - int ret; - - pr_err("Uncorrected hardware memory error in user-access at %llx", m->addr); - if (!(m->mcgstatus & MCG_STATUS_RIPV)) - flags |= MF_MUST_KILL; - ret = memory_failure(m->addr >> PAGE_SHIFT, flags); - if (ret) - pr_err("Memory error not recovered"); - else - set_mce_nospec(m->addr >> PAGE_SHIFT); - return ret; -} - - /* * Cases where we avoid rendezvous handler timeout: * 1) If this CPU is offline. @@ -1204,6 +1189,29 @@ static void __mc_scan_banks(struct mce *m, struct mce *final, *m = *final; } +static void kill_me_now(struct callback_head *ch) +{ + force_sig(SIGBUS); +} + +static void kill_me_maybe(struct callback_head *cb) +{ + struct task_struct *p = container_of(cb, struct task_struct, mce_kill_me); + int flags = MF_ACTION_REQUIRED; + + pr_err("Uncorrected hardware memory error in user-access at %llx", p->mce_addr); + if (!(p->mce_status & MCG_STATUS_RIPV)) + flags |= MF_MUST_KILL; + + if (!memory_failure(p->mce_addr >> PAGE_SHIFT, flags)) { + set_mce_nospec(p->mce_addr >> PAGE_SHIFT); + return; + } + + pr_err("Memory error not recovered"); + kill_me_now(cb); +} + /* * The actual machine check handler. This only handles real * exceptions when something got corrupted coming in through int 18. @@ -1222,7 +1230,7 @@ static void __mc_scan_banks(struct mce *m, struct mce *final, * backing the user stack, tracing that reads the user stack will cause * potentially infinite recursion. */ -void notrace do_machine_check(struct pt_regs *regs, long error_code) +void noinstr do_machine_check(struct pt_regs *regs, long error_code) { DECLARE_BITMAP(valid_banks, MAX_NR_BANKS); DECLARE_BITMAP(toclear, MAX_NR_BANKS); @@ -1259,7 +1267,7 @@ void notrace do_machine_check(struct pt_regs *regs, long error_code) if (__mc_check_crashing_cpu(cpu)) return; - ist_enter(regs); + nmi_enter(); this_cpu_inc(mce_exception_count); @@ -1352,23 +1360,24 @@ void notrace do_machine_check(struct pt_regs *regs, long error_code) /* Fault was in user mode and we need to take some action */ if ((m.cs & 3) == 3) { - ist_begin_non_atomic(regs); - local_irq_enable(); - - if (kill_it || do_memory_failure(&m)) - force_sig(SIGBUS); - local_irq_disable(); - ist_end_non_atomic(); + /* If this triggers there is no way to recover. Die hard. */ + BUG_ON(!on_thread_stack() || !user_mode(regs)); + + current->mce_addr = m.addr; + current->mce_status = m.mcgstatus; + current->mce_kill_me.func = kill_me_maybe; + if (kill_it) + current->mce_kill_me.func = kill_me_now; + task_work_add(current, ¤t->mce_kill_me, true); } else { if (!fixup_exception(regs, X86_TRAP_MC, error_code, 0)) mce_panic("Failed kernel mode recovery", &m, msg); } out_ist: - ist_exit(regs); + nmi_exit(); } EXPORT_SYMBOL_GPL(do_machine_check); -NOKPROBE_SYMBOL(do_machine_check); #ifndef CONFIG_MEMORY_FAILURE int memory_failure(unsigned long pfn, int flags) |