x86, mce: implement the PPro bank 0 quirk in the 64bit machine check code
Quoting the comment:
* SDM documents that on family 6 bank 0 should not be written
* because it aliases to another special BIOS controlled
* register.
* But it's not aliased anymore on model 0x1a+
* Don't ignore bank 0 completely because there could be a valid
* event later, merely don't write CTL0.
This is mostly a port on the 32bit code, except that 32bit
always didn't write it and didn't have the 0x1a heuristic. I checked
with the CPU designers that the quirk is not required starting with
this model.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index cd1313b..1dcd3be 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -65,6 +65,8 @@
static char trigger[128];
static char *trigger_argv[2] = { trigger, NULL };
+static unsigned long dont_init_banks;
+
static DECLARE_WAIT_QUEUE_HEAD(mce_wait);
/* MCA banks polled by the period polling timer for corrected events */
@@ -72,6 +74,11 @@
[0 ... BITS_TO_LONGS(MAX_NR_BANKS)-1] = ~0UL
};
+static inline int skip_bank_init(int i)
+{
+ return i < BITS_PER_LONG && test_bit(i, &dont_init_banks);
+}
+
/* Do initial initialization of a struct mce */
void mce_setup(struct mce *m)
{
@@ -616,6 +623,8 @@
wrmsr(MSR_IA32_MCG_CTL, 0xffffffff, 0xffffffff);
for (i = 0; i < banks; i++) {
+ if (skip_bank_init(i))
+ continue;
wrmsrl(MSR_IA32_MC0_CTL+4*i, bank[i]);
wrmsrl(MSR_IA32_MC0_STATUS+4*i, 0);
}
@@ -643,6 +652,19 @@
}
}
+ if (c->x86_vendor == X86_VENDOR_INTEL) {
+ /*
+ * SDM documents that on family 6 bank 0 should not be written
+ * because it aliases to another special BIOS controlled
+ * register.
+ * But it's not aliased anymore on model 0x1a+
+ * Don't ignore bank 0 completely because there could be a
+ * valid event later, merely don't write CTL0.
+ */
+
+ if (c->x86 == 6 && c->x86_model < 0x1A)
+ __set_bit(0, &dont_init_banks);
+ }
}
static void mce_cpu_features(struct cpuinfo_x86 *c)
@@ -911,8 +933,10 @@
{
int i;
- for (i = 0; i < banks; i++)
- wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+ for (i = 0; i < banks; i++) {
+ if (!skip_bank_init(i))
+ wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+ }
return 0;
}
@@ -1119,8 +1143,10 @@
return;
if (!(action & CPU_TASKS_FROZEN))
cmci_clear();
- for (i = 0; i < banks; i++)
- wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+ for (i = 0; i < banks; i++) {
+ if (!skip_bank_init(i))
+ wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+ }
}
static void mce_reenable_cpu(void *h)
@@ -1133,8 +1159,10 @@
if (!(action & CPU_TASKS_FROZEN))
cmci_reenable();
- for (i = 0; i < banks; i++)
- wrmsrl(MSR_IA32_MC0_CTL + i*4, bank[i]);
+ for (i = 0; i < banks; i++) {
+ if (!skip_bank_init(i))
+ wrmsrl(MSR_IA32_MC0_CTL + i*4, bank[i]);
+ }
}
/* Get notified when a cpu comes on/off. Be hotplug friendly. */
