linux-kernel - [tip: ras/core] x86/mce: Panic for LMCE only if mca

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Date:   Tue, 01 Dec 2020 18:05:54 -0000
From:   "tip-bot2 for Gabriele Paoloni" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Gabriele Paoloni <gabriele.paoloni@...el.com>,
        Borislav Petkov <bp@...e.de>, Tony Luck <tony.luck@...el.com>,
        x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [tip: ras/core] x86/mce: Panic for LMCE only if mca_cfg.tolerant < 3

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

Commit-ID:     3a866b16fd2360a9c4ebf71cfbf7ebfe968c1409
Gitweb:        https://git.kernel.org/tip/3a866b16fd2360a9c4ebf71cfbf7ebfe968c1409
Author:        Gabriele Paoloni <gabriele.paoloni@...el.com>
AuthorDate:    Fri, 27 Nov 2020 16:18:17 
Committer:     Borislav Petkov <bp@...e.de>
CommitterDate: Tue, 01 Dec 2020 18:49:29 +01:00

x86/mce: Panic for LMCE only if mca_cfg.tolerant < 3

Right now for LMCE, if no_way_out is set, mce_panic() is called
regardless of mca_cfg.tolerant. This is not correct as, if
mca_cfg.tolerant = 3, the code should never panic.

Add that check.

 [ bp: use local ptr 'cfg'. ]

Signed-off-by: Gabriele Paoloni <gabriele.paoloni@...el.com>
Signed-off-by: Borislav Petkov <bp@...e.de>
Reviewed-by: Tony Luck <tony.luck@...el.com>
Link: https://lkml.kernel.org/r/20201127161819.3106432-4-gabriele.paoloni@intel.com
---
 arch/x86/kernel/cpu/mce/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index ebaa52a..99da2e0 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1368,7 +1368,7 @@ noinstr void do_machine_check(struct pt_regs *regs)
 	 * to see it will clear it.
 	 */
 	if (lmce) {
-		if (no_way_out)
+		if (no_way_out && cfg->tolerant < 3)
 			mce_panic("Fatal local machine check", &m, msg);
 	} else {
 		order = mce_start(&no_way_out);