linux-kernel - [tip: ras/core] x86/mce/inject: Set the valid bit in MCA

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Date:   Wed, 08 Dec 2021 11:03:43 -0000
From:   "tip-bot2 for Smita Koralahalli" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>,
        Borislav Petkov <bp@...e.de>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: [tip: ras/core] x86/mce/inject: Set the valid bit in MCA_STATUS
 before error injection

The following commit has been merged into the ras/core branch of tip:

Commit-ID:     1e56279a49168f24b2b58e843ae92976f90a98a6
Gitweb:        https://git.kernel.org/tip/1e56279a49168f24b2b58e843ae92976f90a98a6
Author:        Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
AuthorDate:    Thu, 04 Nov 2021 16:58:42 -05:00
Committer:     Borislav Petkov <bp@...e.de>
CommitterDate: Wed, 08 Dec 2021 12:01:01 +01:00

x86/mce/inject: Set the valid bit in MCA_STATUS before error injection

MCA handlers check the valid bit in each status register
(MCA_STATUS[Val]) and continue processing the error only if the valid
bit is set.

Set the valid bit unconditionally in the corresponding MCA_STATUS
register and correct any Val=0 injections made by the user as such
errors will get ignored and such injections will be largely pointless.

Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@....com>
Signed-off-by: Borislav Petkov <bp@...e.de>
Link: https://lore.kernel.org/r/20211104215846.254012-3-Smita.KoralahalliChannabasappa@amd.com
---
 arch/x86/kernel/cpu/mce/inject.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/cpu/mce/inject.c b/arch/x86/kernel/cpu/mce/inject.c
index 725e8e4..6eac840 100644
--- a/arch/x86/kernel/cpu/mce/inject.c
+++ b/arch/x86/kernel/cpu/mce/inject.c
@@ -503,6 +503,8 @@ static void do_inject(void)
 
 	i_mce.tsc = rdtsc_ordered();
 
+	i_mce.status |= MCI_STATUS_VAL;
+
 	if (i_mce.misc)
 		i_mce.status |= MCI_STATUS_MISCV;