x86, AMD: Fix APIC timer erratum 400 affecting K8 Rev.A-E processors
authorBoris Ostrovsky <ostr@amd64.org>
Fri, 29 Apr 2011 21:47:43 +0000 (17:47 -0400)
committerIngo Molnar <mingo@elte.hu>
Sun, 1 May 2011 16:55:51 +0000 (18:55 +0200)
commite20a2d205c05cef6b5783df339a7d54adeb50962
tree41bc3658f7c7f437093bf1a693e320f917e4b87c
parent3fd9952df4964fac7d5868ba48eadcc9dae3ba46
x86, AMD: Fix APIC timer erratum 400 affecting K8 Rev.A-E processors

Older AMD K8 processors (Revisions A-E) are affected by erratum
400 (APIC timer interrupts don't occur in C states greater than
C1). This, for example, means that X86_FEATURE_ARAT flag should
not be set for these parts.

This addresses regression introduced by commit
b87cf80af3ba4b4c008b4face3c68d604e1715c6 ("x86, AMD: Set ARAT
feature on AMD processors") where the system may become
unresponsive until external interrupt (such as keyboard input)
occurs. This results, for example, in time not being reported
correctly, lack of progress on the system and other lockups.

Reported-by: Joerg-Volker Peetz <jvpeetz@web.de>
Tested-by: Joerg-Volker Peetz <jvpeetz@web.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Boris Ostrovsky <Boris.Ostrovsky@amd.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1304113663-6586-1-git-send-email-ostr@amd64.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/cpu/amd.c