kgdb: fix NMI hangs
authorJason Wessel <jason.wessel@windriver.com>
Fri, 15 Feb 2008 20:55:53 +0000 (14:55 -0600)
committerIngo Molnar <mingo@elte.hu>
Thu, 17 Apr 2008 18:05:38 +0000 (20:05 +0200)
commitd359752407f8916c29ad53a5c30ac73e338f2797
tree529406a1a001a33546d7044d7d23bf8659a81962
parentc191e5ad6b3fd8cc84b2b6d62c02fcd6837c8a8f
kgdb: fix NMI hangs

This patch fixes the hang regression with kgdb when the NMI interrupt
comes in while the master core is returning from an exception.

Adjust the NMI logic such that KGDB will not stop NMI exceptions from
occurring by in general returning NOTIFY_DONE.  It is not possible to
distinguish the debug NMI sync vs the normal NMI apic interrupt so
kgdb needs to catch the unknown NMI if it the debugger was previously
active on one of the cpus.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/kgdb.c
arch/x86/kernel/traps_32.c
arch/x86/kernel/traps_64.c
include/asm-x86/kdebug.h