x86, MCE, AMD: Disable error thresholding bank 4 on some models
Turn off MC4_MISC thresholding banks on models which have them but that
particular processor implementation does not supply applicable error
sources to be counted.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index d086a09..888fbf9 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1423,6 +1423,43 @@
*/
if (c->x86 == 6 && banks > 0)
mce_banks[0].ctl = 0;
+
+ /*
+ * Turn off MC4_MISC thresholding banks on those models since
+ * they're not supported there.
+ */
+ if (c->x86 == 0x15 &&
+ (c->x86_model >= 0x10 && c->x86_model <= 0x1f)) {
+ int i;
+ u64 val, hwcr;
+ bool need_toggle;
+ u32 msrs[] = {
+ 0x00000413, /* MC4_MISC0 */
+ 0xc0000408, /* MC4_MISC1 */
+ };
+
+ rdmsrl(MSR_K7_HWCR, hwcr);
+
+ /* McStatusWrEn has to be set */
+ need_toggle = !(hwcr & BIT(18));
+
+ if (need_toggle)
+ wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
+
+ for (i = 0; i < ARRAY_SIZE(msrs); i++) {
+ rdmsrl(msrs[i], val);
+
+ /* CntP bit set? */
+ if (val & BIT(62)) {
+ val &= ~BIT(62);
+ wrmsrl(msrs[i], val);
+ }
+ }
+
+ /* restore old settings */
+ if (need_toggle)
+ wrmsrl(MSR_K7_HWCR, hwcr);
+ }
}
if (c->x86_vendor == X86_VENDOR_INTEL) {