+ kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler.patch added to -mm tree

+ kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler.patch added to -mm tree

[akpm]

The patch titled
     Subject: kernel/watchdog: use nmi registers snapshot in hardlockup handler
has been added to the -mm tree.  Its filename is
     kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler.patch

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------------------------------------------------------
From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Subject: kernel/watchdog: use nmi registers snapshot in hardlockup handler

NMI handler doesn't call set_irq_regs(), so get_irq_regs() returns NULL or
stale snapshot from beginning of IRQ interrupted by NMI.  Registers from
argument are always here and points to interrupted instruction and state.

Link: http://lkml.kernel.org/r/146771764784.86724.6006627197118544150.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/watchdog.c |    1 -
 1 file changed, 1 deletion(-)

diff -puN kernel/watchdog.c~kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler kernel/watchdog.c
--- a/kernel/watchdog.c~kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler
+++ a/kernel/watchdog.c
@@ -344,7 +344,6 @@ static void watchdog_overflow_callback(s
 	 */
 	if (is_hardlockup()) {
 		int this_cpu = smp_processor_id();
-		struct pt_regs *regs = get_irq_regs();
 
 		/* only print hardlockups once */
 		if (__this_cpu_read(hard_watchdog_warn) == true)
_

Patches currently in -mm which might be from khlebnikov@yandex-team.ru are

kernel-watchdog-use-nmi-registers-snapshot-in-hardlockup-handler.patch