[PATCH 4.15 062/146] x86/MCE: Save microcode revision in machine check records

From: Greg Kroah-Hartman
Date: Tue Mar 13 2018 - 12:54:45 EST


4.15-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tony Luck <tony.luck@xxxxxxxxx>

commit fa94d0c6e0f3431523f5701084d799c77c7d4a4f upstream.

Updating microcode used to be relatively rare. Now that it has become
more common we should save the microcode version in a machine check
record to make sure that those people looking at the error have this
important information bundled with the rest of the logged information.

[ Borislav: Simplify a bit. ]

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Yazen Ghannam <yazen.ghannam@xxxxxxx>
Cc: linux-edac <linux-edac@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20180301233449.24311-1-tony.luck@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/x86/include/uapi/asm/mce.h | 1 +
arch/x86/kernel/cpu/mcheck/mce.c | 4 +++-
2 files changed, 4 insertions(+), 1 deletion(-)

--- a/arch/x86/include/uapi/asm/mce.h
+++ b/arch/x86/include/uapi/asm/mce.h
@@ -30,6 +30,7 @@ struct mce {
__u64 synd; /* MCA_SYND MSR: only valid on SMCA systems */
__u64 ipid; /* MCA_IPID MSR: only valid on SMCA systems */
__u64 ppin; /* Protected Processor Inventory Number */
+ __u32 microcode;/* Microcode revision */
};

#define MCE_GET_RECORD_LEN _IOR('M', 1, int)
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -131,6 +131,8 @@ void mce_setup(struct mce *m)

if (this_cpu_has(X86_FEATURE_INTEL_PPIN))
rdmsrl(MSR_PPIN, m->ppin);
+
+ m->microcode = boot_cpu_data.microcode;
}

DEFINE_PER_CPU(struct mce, injectm);
@@ -263,7 +265,7 @@ static void __print_mce(struct mce *m)
*/
pr_emerg(HW_ERR "PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x microcode %x\n",
m->cpuvendor, m->cpuid, m->time, m->socketid, m->apicid,
- cpu_data(m->extcpu).microcode);
+ m->microcode);
}

static void print_mce(struct mce *m)