Commit-ID: 32b40a82e84414499bb4d635cafb9de9e45e6c38 Gitweb: http://git.kernel.org/tip/32b40a82e84414499bb4d635cafb9de9e45e6c38 Author: Borislav Petkov <b...@suse.de> AuthorDate: Mon, 27 Mar 2017 11:33:04 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 28 Mar 2017 08:55:15 +0200
x86/mce: Do not register notifiers with invalid prio This is just a defensive precaution: do not register notifiers with a priority which would disrupt the error handling in the notifiers with prio higher than MCE_PRIO_EDAC. Signed-off-by: Borislav Petkov <b...@suse.de> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: linux-edac <linux-e...@vger.kernel.org> Link: http://lkml.kernel.org/r/20170327093304.10683-7...@alien8.de Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/kernel/cpu/mcheck/mce.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 36082c7..a09bb67 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -157,9 +157,10 @@ static atomic_t num_notifiers; void mce_register_decode_chain(struct notifier_block *nb) { - atomic_inc(&num_notifiers); + if (WARN_ON(nb->priority > MCE_PRIO_LOWEST && nb->priority < MCE_PRIO_EDAC)) + return; - WARN_ON(nb->priority > MCE_PRIO_LOWEST && nb->priority < MCE_PRIO_EDAC); + atomic_inc(&num_notifiers); atomic_notifier_chain_register(&x86_mce_decoder_chain, nb); }
