linux-kernel - [PATCH 2/2] x86: re-enable MCE on secondary CPUS after suspend/resume

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 12 Dec 2008 19:10:21 +0100
From:	Andreas Herrmann <andreas.herrmann3@....com>
To:	Ingo Molnar <mingo@...e.hu>, Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>
CC:	linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] x86: re-enable MCE on secondary CPUS after
	suspend/resume

Impact: fix suspend/resume bug with MCE

After suspend/resume MCx_CTL registers of secondary CPUs are cleared.
(At least that's what I've observed on several systems.)
Linux currently only re-initializes MCE on the boot CPU - see mce_resume().
Thus after suspend/resume we end up with a system where MCE is active
on the boot CPU but switched off on all other CPUs.

By calling mce_init() whenever a CPU comes online this problem is
solved.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@....com>
---
 arch/x86/kernel/cpu/mcheck/mce_64.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c
index e2d9649..0174539 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -889,6 +889,7 @@ static int __cpuinit mce_cpu_callback(struct notifier_block *nfb,
 		mce_create_device(cpu);
 		if (threshold_cpu_callback)
 			threshold_cpu_callback(action, cpu);
+		mce_init(NULL);
 		break;
 	case CPU_DEAD:
 	case CPU_DEAD_FROZEN:
-- 
1.6.0.4



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/