[PATCH AUTOSEL 5.4 079/130] x86/mce: Panic for LMCE only if mca_cfg.tolerant < 3

From: Sasha Levin
Date: Tue Dec 22 2020 - 21:21:20 EST


From: Gabriele Paoloni <gabriele.paoloni@xxxxxxxxx>

[ Upstream commit 3a866b16fd2360a9c4ebf71cfbf7ebfe968c1409 ]

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@xxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
Link: https://lkml.kernel.org/r/20201127161819.3106432-4-gabriele.paoloni@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 10f69e045d3ea..344fe08779824 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1344,7 +1344,7 @@ void do_machine_check(struct pt_regs *regs, long error_code)
* 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);
--
2.27.0