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x86/MCE: Extend table to report action optional errors through CMCI too

PATCH New Borislav Petkov 1 participant 2 messages Dec 4, 2017

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Borislav Petkov

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#0 lore raw

PATCH 1/2 x86/MCE: Extend table to report action optional errors through CMCI too

From: Xie XiuQi <[email protected]>

According to the Intel SDM Volume 3B (253669-063US, July 2017), action optional (SRAO) errors can be reported either via MCE or CMC:

In cases when SRAO is signaled via CMCI the error signature is indicated via UC=1, PCC=0, S=0.

Type(*1) UC EN PCC S AR Signaling
---------------------------------------------------------------
UC 1 1 1 x x MCE
SRAR 1 1 0 1 1 MCE
SRAO 1 x(*2) 0 x(*2) 0 MCE/CMC
UCNA 1 x 0 0 0 CMC
CE 0 x x x x CMC

NOTES:
1. SRAR, SRAO and UCNA errors are supported by the processor only

     when IA32_MCG_CAP[24] (MCG_SER_P) is set.

2. EN=1, S=1 when signaled via MCE. EN=x, S=0 when signaled via CMC.

And there is a description in 15.6.2 UCR Error Reporting and Logging, for bit S:

S (Signaling) flag, bit 56 - Indicates (when set) that a machine check exception was generated for the UCR error reported in this MC bank... When the S flag in the IA32_MCi_STATUS register is clear, this UCR error was not signaled via a machine check exception and instead was reported as a corrected machine check (CMC).

So merge the two cases and just remove the S=0 check for SRAO in mce_severity().

---
 arch/x86/kernel/cpu/mcheck/mce-severity.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)
arch/x86/kernel/cpu/mcheck/mce-severity.c +17 -9
index 4ca632a06e0b..5bbd06f38ff6 100644
@@ -59,6 +59,7 @@ static struct severity {
 #define  MCGMASK(x, y)	.mcgmask = x, .mcgres = y
 #define  MASK(x, y)	.mask = x, .result = y
 #define MCI_UC_S (MCI_STATUS_UC|MCI_STATUS_S)
+#define MCI_UC_AR (MCI_STATUS_UC|MCI_STATUS_AR)
 #define MCI_UC_SAR (MCI_STATUS_UC|MCI_STATUS_S|MCI_STATUS_AR)
 #define	MCI_ADDR (MCI_STATUS_ADDRV|MCI_STATUS_MISCV)
 
@@ -101,6 +102,22 @@ static struct severity {
 		NOSER, BITCLR(MCI_STATUS_UC)
 		),
 
+	/*
+	 * known AO MCACODs reported via MCE or CMC:
+	 *
+	 * SRAO could be signaled either via a machine check exception or
+	 * CMCI with the corresponding bit S 1 or 0. So we don't need to
+	 * check bit S for SRAO.
+	 */
+	MCESEV(
+		AO, "Action optional: memory scrubbing error",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_AR|MCACOD_SCRUBMSK, MCI_STATUS_UC|MCACOD_SCRUB)
+		),
+	MCESEV(
+		AO, "Action optional: last level cache writeback error",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_AR|MCACOD, MCI_STATUS_UC|MCACOD_L3WB)
+		),
+
 	/* ignore OVER for UCNA */
 	MCESEV(
 		UCNA, "Uncorrected no action required",
@@ -149,15 +166,6 @@ static struct severity {
 		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_UC_SAR)
 		),
 
-	/* known AO MCACODs: */
-	MCESEV(
-		AO, "Action optional: memory scrubbing error",
-		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCACOD_SCRUBMSK, MCI_UC_S|MCACOD_SCRUB)
-		),
-	MCESEV(
-		AO, "Action optional: last level cache writeback error",
-		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCACOD, MCI_UC_S|MCACOD_L3WB)
-		),
 	MCESEV(
 		SOME, "Action optional: unknown MCACOD",
 		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_UC_S)
author maintainer
#1 lore raw

PATCH 2/2 x86/mce/AMD: Don't set DEF_INT_TYPE in MSR_CU_DEF_ERR on SMCA systems

From: Yazen Ghannam <[email protected]>

The McaIntrCfg register (MSRC000_0410), previously known as CU_DEFER_ERR, is used on SMCA systems to set the LVT offset for the Threshold and Deferred error interrupts.

This register was used on non-SMCA systems to also set the Deferred interrupt type in bits 2:1. However, these bits are reserved on SMCA systems.

Only set MSRC000_0410[2:1] on non-SMCA systems.

---
 arch/x86/kernel/cpu/mcheck/mce_amd.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
arch/x86/kernel/cpu/mcheck/mce_amd.c +3 -1
index 486f640b02ef..a38ab1fa53a2 100644
@@ -407,7 +407,9 @@ static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
 	    (deferred_error_int_vector != amd_deferred_error_interrupt))
 		deferred_error_int_vector = amd_deferred_error_interrupt;
 
-	low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
+	if (!mce_flags.smca)
+		low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
+
 	wrmsr(MSR_CU_DEF_ERR, low, high);
 }