[PATCH] x86/mce: Do Deferred error check for CEC

[Yazen Ghannam]

From: Yazen Ghannam <yazen.ghan...@amd.com>

AMD systems may log Deferred errors. These are errors that are uncorrected
but which do not need immediate action. The MCA_STATUS[UC] bit may not be
set for Deferred errors.

Flag the error as not correctable when MCA_STATUS[Deferred] is set.

Signed-off-by: Yazen Ghannam <yazen.ghan...@amd.com>
Cc: sta...@vger.kernel.org # 4.13.x
---
 arch/x86/kernel/cpu/mcheck/mce.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 321c7a80be66..1b2c11473376 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -528,6 +528,17 @@ bool mce_is_memory_error(struct mce *m)
 }
 EXPORT_SYMBOL_GPL(mce_is_memory_error);
 
+static bool mce_is_correctable(struct mce *m)
+{
+       if (m->cpuvendor == X86_VENDOR_AMD && m->status & MCI_STATUS_DEFERRED)
+               return false;
+
+       if (m->status & MCI_STATUS_UC)
+               return false;
+
+       return true;
+}
+
 static bool cec_add_mce(struct mce *m)
 {
        if (!m)
@@ -535,7 +546,7 @@ static bool cec_add_mce(struct mce *m)
 
        /* We eat only correctable DRAM errors with usable addresses. */
        if (mce_is_memory_error(m) &&
-           !(m->status & MCI_STATUS_UC) &&
+           mce_is_correctable(m)  &&
            mce_usable_address(m))
                if (!cec_add_elem(m->addr >> PAGE_SHIFT))
                        return true;
-- 
2.14.1