x86/mce/AMD: Collect error info even if valid bits are not set

The MCA banks log error info into MCA_ADDR, MCA_MISC0, and MCA_SYND even
if the corresponding valid bits are not set:

"Error handlers should save the values in MCA_ADDR, MCA_MISC0,
and MCA_SYND even if MCA_STATUS[AddrV], MCA_STATUS[MiscV], and
MCA_STATUS[SyndV] are zero."

Do so by setting those bits so that code down the MCE processing path
doesn't need to be changed.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20180221101900.10326-5-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index d7dff23..3c9a25b 100644 (file)
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -441,6 +441,20 @@ static inline void mce_gather_info(struct mce *m, struct pt_regs *regs)
                if (mca_cfg.rip_msr)
                        m->ip = mce_rdmsrl(mca_cfg.rip_msr);
        }
+
+       /*
+        * Error handlers should save the values in MCA_ADDR, MCA_MISC0, and
+        * MCA_SYND even if MCA_STATUS[AddrV], MCA_STATUS[MiscV], and
+        * MCA_STATUS[SyndV] are zero.
+        */
+       if (m->cpuvendor == X86_VENDOR_AMD) {
+               u64 status = MCI_STATUS_ADDRV | MCI_STATUS_MISCV;
+
+               if (mce_flags.smca)
+                       status |= MCI_STATUS_SYNDV;
+
+               m->status |= status;
+       }
 }
 
 int mce_available(struct cpuinfo_x86 *c)