x86/MCE: Export memory_error()

commit 2d1f406139ec20320bf38bcd2461aa8e358084b5 upstream.

Export the function which checks whether an MCE is a memory error to
other users so that we can reuse the logic. Drop the boot_cpu_data use,
while at it, as mce.cpuvendor already has the CPU vendor in there.

Integrate a piece from a patch from Vishal Verma
<vishal.l.verma@intel.com> to export it for modules (nfit).

The main reason we're exporting it is that the nfit handler
nfit_handle_mce() needs to detect a memory error properly before doing
its recovery actions.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Link: http://lkml.kernel.org/r/20170519093915.15413-2-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 9bd7ff5..70c9cc3 100644 (file)
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -257,6 +257,7 @@ static inline void mce_amd_feature_init(struct cpuinfo_x86 *c) { }
 #endif
 
 int mce_available(struct cpuinfo_x86 *c);
+bool mce_is_memory_error(struct mce *m);
 
 DECLARE_PER_CPU(unsigned, mce_exception_count);
 DECLARE_PER_CPU(unsigned, mce_poll_count);

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 22cda29..8ca5f8a 100644 (file)
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -598,16 +598,14 @@ static void mce_read_aux(struct mce *m, int i)
        }
 }
 
-static bool memory_error(struct mce *m)
+bool mce_is_memory_error(struct mce *m)
 {
-       struct cpuinfo_x86 *c = &boot_cpu_data;
-
-       if (c->x86_vendor == X86_VENDOR_AMD) {
+       if (m->cpuvendor == X86_VENDOR_AMD) {
                /* ErrCodeExt[20:16] */
                u8 xec = (m->status >> 16) & 0x1f;
 
                return (xec == 0x0 || xec == 0x8);
-       } else if (c->x86_vendor == X86_VENDOR_INTEL) {
+       } else if (m->cpuvendor == X86_VENDOR_INTEL) {
                /*
                 * Intel SDM Volume 3B - 15.9.2 Compound Error Codes
                 *
@@ -628,6 +626,7 @@ static bool memory_error(struct mce *m)
 
        return false;
 }
+EXPORT_SYMBOL_GPL(mce_is_memory_error);
 
 DEFINE_PER_CPU(unsigned, mce_poll_count);
 
@@ -691,7 +690,7 @@ bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
 
                severity = mce_severity(&m, mca_cfg.tolerant, NULL, false);
 
-               if (severity == MCE_DEFERRED_SEVERITY && memory_error(&m))
+               if (severity == MCE_DEFERRED_SEVERITY && mce_is_memory_error(&m))
                        if (m.status & MCI_STATUS_ADDRV)
                                m.severity = severity;