[PATCH 4.4 183/266] x86/MCE: Save microcode revision in machine check records

From: Greg Kroah-Hartman
Date: Wed May 15 2019 - 07:11:23 EST


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>
Link: http://lkml.kernel.org/r/20180301233449.24311-1-tony.luck@xxxxxxxxx
[bwh: Backported to 4.4:
- Also add earlier fields to struct mce, to match upstream UAPI
- Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/uapi/asm/mce.h | 4 ++++
arch/x86/kernel/cpu/mcheck/mce.c | 4 +++-
2 files changed, 7 insertions(+), 1 deletion(-)

--- a/arch/x86/include/uapi/asm/mce.h
+++ b/arch/x86/include/uapi/asm/mce.h
@@ -26,6 +26,10 @@ struct mce {
__u32 socketid; /* CPU socket ID */
__u32 apicid; /* CPU initial apic ID */
__u64 mcgcap; /* MCGCAP MSR: machine check capabilities of CPU */
+ __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
@@ -138,6 +138,8 @@ void mce_setup(struct mce *m)
m->socketid = cpu_data(m->extcpu).phys_proc_id;
m->apicid = cpu_data(m->extcpu).initial_apicid;
rdmsrl(MSR_IA32_MCG_CAP, m->mcgcap);
+
+ m->microcode = boot_cpu_data.microcode;
}

DEFINE_PER_CPU(struct mce, injectm);
@@ -258,7 +260,7 @@ 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);

/*
* Print out human-readable details about the MCE error,