From: Tony Luck Date: Fri, 14 Feb 2020 22:27:18 +0000 (-0800) Subject: x86/mce: Change default MCE logger to check mce->kflags X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=925946cfa715a5a71639528f82b98e58f14dd4cb;p=linux.git x86/mce: Change default MCE logger to check mce->kflags Instead of keeping count of how many handlers are registered on the MCE notifier chain and printing if below some magic value, look at mce->kflags to see if anyone claims to have handled/logged this error. [ bp: Do not print ->kflags in __print_mce(). ] Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Tested-by: Tony Luck Link: https://lkml.kernel.org/r/20200214222720.13168-6-tony.luck@intel.com --- diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 5666a48a4bc9a..fc879b6669d5f 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -158,29 +158,17 @@ void mce_log(struct mce *m) } EXPORT_SYMBOL_GPL(mce_log); -/* - * We run the default notifier if we have only the UC, the first and the - * default notifier registered. I.e., the mandatory NUM_DEFAULT_NOTIFIERS - * notifiers registered on the chain. - */ -#define NUM_DEFAULT_NOTIFIERS 3 -static atomic_t num_notifiers; - void mce_register_decode_chain(struct notifier_block *nb) { if (WARN_ON(nb->priority > MCE_PRIO_MCELOG && nb->priority < MCE_PRIO_EDAC)) return; - atomic_inc(&num_notifiers); - blocking_notifier_chain_register(&x86_mce_decoder_chain, nb); } EXPORT_SYMBOL_GPL(mce_register_decode_chain); void mce_unregister_decode_chain(struct notifier_block *nb) { - atomic_dec(&num_notifiers); - blocking_notifier_chain_unregister(&x86_mce_decoder_chain, nb); } EXPORT_SYMBOL_GPL(mce_unregister_decode_chain); @@ -263,6 +251,7 @@ static void __print_mce(struct mce *m) } pr_cont("\n"); + /* * Note this output is parsed by external tools and old fields * should not be changed. @@ -602,10 +591,8 @@ static int mce_default_notifier(struct notifier_block *nb, unsigned long val, if (!m) return NOTIFY_DONE; - if (atomic_read(&num_notifiers) > NUM_DEFAULT_NOTIFIERS) - return NOTIFY_DONE; - - __print_mce(m); + if (!m->kflags) + __print_mce(m); return NOTIFY_DONE; }