x86/mce: Handle broadcasted MCE gracefully with kexec

When we are about to kexec a crash kernel and right then and there a
broadcasted MCE fires while we're still in the first kernel and while
the other CPUs remain in a holding pattern, the #MC handler of the
first kernel will timeout and then panic due to never completing MCE
synchronization.

Handle this in a similar way as to when the CPUs are offlined when that
broadcasted MCE happens.

[ Boris: rewrote commit message and comments. ]

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: kexec@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1487857012-9059-1-git-send-email-xlpang@redhat.com
Link: http://lkml.kernel.org/r/20170313095019.19351-1-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Xunlei Pang
2017-03-13 10:50:19 +01:00
committed by Thomas Gleixner
parent 4495c08e84
commit 5bc329503e
3 changed files with 20 additions and 4 deletions

View File

@@ -765,10 +765,11 @@ void machine_crash_shutdown(struct pt_regs *regs)
#endif
/* This is the CPU performing the emergency shutdown work. */
int crashing_cpu = -1;
#if defined(CONFIG_SMP)
/* This keeps a track of which one is crashing cpu. */
static int crashing_cpu;
static nmi_shootdown_cb shootdown_callback;
static atomic_t waiting_for_crash_ipi;