4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yazen Ghannam <Yazen.Ghannam@xxxxxxx> commit fead35c68926682c90c995f22b48f1c8d78865c1 upstream. Check the MCG_STATUS_LMCES bit on Intel to verify that current MCE is local. It is always local on AMD. Signed-off-by: Yazen Ghannam <Yazen.Ghannam@xxxxxxx> [ Massaged it a bit. Reflowed comments. Shut up -Wmaybe-uninitialized. ] Signed-off-by: Borislav Petkov <bp@xxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: linux-edac <linux-edac@xxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1462019637-16474-8-git-send-email-bp@xxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/mcheck/mce.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -980,11 +980,12 @@ void do_machine_check(struct pt_regs *re int i; int worst = 0; int severity; + /* * Establish sequential order between the CPUs entering the machine * check handler. */ - int order; + int order = -1; /* * If no_way_out gets set, there is no safe way to recover from this * MCE. If mca_cfg.tolerant is cranked up, we'll try anyway. @@ -1000,7 +1001,12 @@ void do_machine_check(struct pt_regs *re char *msg = "Unknown"; u64 recover_paddr = ~0ull; int flags = MF_ACTION_REQUIRED; - int lmce = 0; + + /* + * MCEs are always local on AMD. Same is determined by MCG_STATUS_LMCES + * on Intel. + */ + int lmce = 1; /* If this CPU is offline, just bail out. */ if (cpu_is_offline(smp_processor_id())) { @@ -1039,19 +1045,20 @@ void do_machine_check(struct pt_regs *re kill_it = 1; /* - * Check if this MCE is signaled to only this logical processor + * Check if this MCE is signaled to only this logical processor, + * on Intel only. */ - if (m.mcgstatus & MCG_STATUS_LMCES) - lmce = 1; - else { - /* - * Go through all the banks in exclusion of the other CPUs. - * This way we don't report duplicated events on shared banks - * because the first one to see it will clear it. - * If this is a Local MCE, then no need to perform rendezvous. - */ + if (m.cpuvendor == X86_VENDOR_INTEL) + lmce = m.mcgstatus & MCG_STATUS_LMCES; + + /* + * Go through all banks in exclusion of the other CPUs. This way we + * don't report duplicated events on shared banks because the first one + * to see it will clear it. If this is a Local MCE, then no need to + * perform rendezvous. + */ + if (!lmce) order = mce_start(&no_way_out); - } for (i = 0; i < cfg->banks; i++) { __clear_bit(i, toclear);
