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authorJoerg Roedel <joerg.roedel@amd.com>2011-04-15 16:47:40 +0400
committerH. Peter Anvin <hpa@linux.intel.com>2011-04-16 03:03:16 +0400
commit5bbc097d890409d8eff4e3f1d26f11a9d6b7c07e (patch)
tree006300196d8ec4d5ed8e48a7b465f23f7209b731 /arch/x86/kernel/cpu/amd.c
parent7d6b46707f2491a94f4bd3b4329d2d7f809e9368 (diff)
downloadlinux-5bbc097d890409d8eff4e3f1d26f11a9d6b7c07e.tar.xz
x86, amd: Disable GartTlbWlkErr when BIOS forgets it
This patch disables GartTlbWlk errors on AMD Fam10h CPUs if the BIOS forgets to do is (or is just too old). Letting these errors enabled can cause a sync-flood on the CPU causing a reboot. The AMD BKDG recommends disabling GART TLB Wlk Error completely. This patch is the fix for https://bugzilla.kernel.org/show_bug.cgi?id=33012 on my machine. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Link: http://lkml.kernel.org/r/20110415131152.GJ18463@8bytes.org Tested-by: Alexandre Demers <alexandre.f.demers@gmail.com> Cc: <stable@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
-rw-r--r--arch/x86/kernel/cpu/amd.c19
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 3ecece0217ef..3532d3bf8105 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -615,6 +615,25 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
/* As a rule processors have APIC timer running in deep C states */
if (c->x86 >= 0xf && !cpu_has_amd_erratum(amd_erratum_400))
set_cpu_cap(c, X86_FEATURE_ARAT);
+
+ /*
+ * Disable GART TLB Walk Errors on Fam10h. We do this here
+ * because this is always needed when GART is enabled, even in a
+ * kernel which has no MCE support built in.
+ */
+ if (c->x86 == 0x10) {
+ /*
+ * BIOS should disable GartTlbWlk Errors themself. If
+ * it doesn't do it here as suggested by the BKDG.
+ *
+ * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
+ */
+ u64 mask;
+
+ rdmsrl(MSR_AMD64_MCx_MASK(4), mask);
+ mask |= (1 << 10);
+ wrmsrl(MSR_AMD64_MCx_MASK(4), mask);
+ }
}
#ifdef CONFIG_X86_32