linux-kernel - [PATCH v3 2/2] x86/mce/dev-mcelog: Fix updating kflags in AMD systems

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Message-Id: <20200903234531.162484-3-Smita.KoralahalliChannabasappa@amd.com>
Date:   Thu,  3 Sep 2020 18:45:31 -0500
From:   Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
To:     x86@...nel.org, linux-kernel@...r.kernel.org,
        linux-pm@...r.kernel.org, linux-edac@...r.kernel.org,
        linux-efi@...r.kernel.org, linux-acpi@...r.kernel.org,
        devel@...ica.org
Cc:     Borislav Petkov <bp@...en8.de>, Tony Luck <tony.luck@...el.com>,
        "Rafael J . Wysocki" <rjw@...ysocki.net>,
        Len Brown <len.brown@...el.com>,
        Ard Biesheuvel <ardb@...nel.org>,
        Yazen Ghannam <yazen.ghannam@....com>,
        Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
Subject: [PATCH v3 2/2] x86/mce/dev-mcelog: Fix updating kflags in AMD systems

The mcelog utility is not commonly used on AMD systems. Therefore, errors
logged only by the dev_mce_log() notifier will be missed. This may occur
if the EDAC modules are not loaded in which case it's preferable to print
the error record by the default notifier.

However, the mce->kflags set by dev_mce_log() notifier makes the default
notifier to skip over the errors assuming they are processed by
dev_mce_log().

Do not update kflags in the dev_mce_log() notifier on AMD systems.

Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
---
Link:
https://lkml.kernel.org/r/20200828203332.11129-3-Smita.KoralahalliChannabasappa@amd.com

v3:
	No change
v2:
	No change
---
 arch/x86/kernel/cpu/mce/dev-mcelog.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mce/dev-mcelog.c b/arch/x86/kernel/cpu/mce/dev-mcelog.c
index 03e51053592a..100fbeebdc72 100644
--- a/arch/x86/kernel/cpu/mce/dev-mcelog.c
+++ b/arch/x86/kernel/cpu/mce/dev-mcelog.c
@@ -67,7 +67,9 @@ static int dev_mce_log(struct notifier_block *nb, unsigned long val,
 unlock:
 	mutex_unlock(&mce_chrdev_read_mutex);
 
-	mce->kflags |= MCE_HANDLED_MCELOG;
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
+		mce->kflags |= MCE_HANDLED_MCELOG;
+
 	return NOTIFY_OK;
 }
 
-- 
2.17.1