From b9c582a117a0d590b7a174760b662d25761692d4 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Tue, 17 May 2011 14:55:19 +0200 Subject: [PATCH] x86, AMD: Fix ARAT feature setting again commit 14fb57dccb6e1defe9f89a66f548fcb24c374c1d upstream. Trying to enable the local APIC timer on early K8 revisions uncovers a number of other issues with it, in conjunction with the C1E enter path on AMD. Fixing those causes much more churn and troubles than the benefit of using that timer brings so don't enable it on K8 at all, falling back to the original functionality the kernel had wrt to that. Reported-and-bisected-by: Nick Bowler Cc: Boris Ostrovsky Cc: Andreas Herrmann Cc: Greg Kroah-Hartman Cc: Hans Rosenfeld Cc: Nick Bowler Cc: Joerg-Volker-Peetz Signed-off-by: Borislav Petkov Signed-off-by: Andi Kleen Link: http://lkml.kernel.org/r/1305636919-31165-3-git-send-email-bp@amd64.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/amd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index b203d0dbfc04..38254806bf31 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -566,7 +566,7 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c) #endif /* As a rule processors have APIC timer running in deep C states */ - if (c->x86 >= 0xf && !cpu_has_amd_erratum(amd_erratum_400)) + if (c->x86 > 0xf && !cpu_has_amd_erratum(amd_erratum_400)) set_cpu_cap(c, X86_FEATURE_ARAT); /* -- 2.39.5