x86/MCE: Report only DRAM ECC as memory errors on AMD systems

The MCA_STATUS[ErrorCodeExt] field is very bank type specific.
We currently check if the ErrorCodeExt value is 0x0 or 0x8 in
mce_is_memory_error(), but we don't check the bank number. This means
that we could flag non-memory errors as memory errors.

We know that we want to flag DRAM ECC errors as memory errors, so let's do
those cases first. We can add more cases later when needed.

Define a wrapper function in mce_amd.c so we can use SMCA enums.

[ bp: Remove brackets around return statements. ]

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171207203955.118171-2-Yazen.Ghannam@amd.com

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 661c4738be27..0f32ad242324 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -754,6 +754,17 @@ out_err:
 }
 EXPORT_SYMBOL_GPL(umc_normaddr_to_sysaddr);
 
+bool amd_mce_is_memory_error(struct mce *m)
+{
+	/* ErrCodeExt[20:16] */
+	u8 xec = (m->status >> 16) & 0x1f;
+
+	if (mce_flags.smca)
+		return smca_get_bank_type(m) == SMCA_UMC && xec == 0x0;
+
+	return m->bank == 4 && xec == 0x8;
+}
+
 static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)
 {
 	struct mce m;