linux-kernel - [PATCH] x86/mce: Include a MCi

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Message-Id: <20210527222846.931851-1-tony.luck@intel.com>
Date:   Thu, 27 May 2021 15:28:46 -0700
From:   Tony Luck <tony.luck@...el.com>
To:     Borislav Petkov <bp@...en8.de>
Cc:     Tony Luck <tony.luck@...el.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org, linux-edac@...r.kernel.org
Subject: [PATCH] x86/mce: Include a MCi_MISC value in faked mce logs

When BIOS reports memory errors to Linux using the ACPI/APEI
error reporting method Linux creates a "struct mce" to pass
to the normal reporting code path.

The constructed record doesn't include a value for the "misc"
field of the structure, and so mce_usable_address() says this
record doesn't include a valid address.

Net result is that functions like uc_decode_notifier() will
just ignore this record instead of taking action to offline
a page.

Signed-off-by: Tony Luck <tony.luck@...el.com>
---
 arch/x86/kernel/cpu/mce/apei.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mce/apei.c b/arch/x86/kernel/cpu/mce/apei.c
index b58b85380ddb..0e3ae64d3b76 100644
--- a/arch/x86/kernel/cpu/mce/apei.c
+++ b/arch/x86/kernel/cpu/mce/apei.c
@@ -36,7 +36,8 @@ void apei_mce_report_mem_error(int severity, struct cper_sec_mem_err *mem_err)
 	mce_setup(&m);
 	m.bank = -1;
 	/* Fake a memory read error with unknown channel */
-	m.status = MCI_STATUS_VAL | MCI_STATUS_EN | MCI_STATUS_ADDRV | 0x9f;
+	m.status = MCI_STATUS_VAL | MCI_STATUS_EN | MCI_STATUS_ADDRV | MCI_STATUS_MISCV | 0x9f;
+	m.misc = (MCI_MISC_ADDR_PHYS << 6) | PAGE_SHIFT;
 
 	if (severity >= GHES_SEV_RECOVERABLE)
 		m.status |= MCI_STATUS_UC;
-- 
2.29.2