Messages in this thread | | | Date | Mon, 23 Jan 2017 10:01:53 -0800 | From | "Luck, Tony" <> | Subject | Re: [PATCH] x86/mce: Keep quiet in case of broadcasted mce after system panic |
| |
On Mon, Jan 23, 2017 at 06:51:30PM +0100, Borislav Petkov wrote: > Hey Tony, > > a "welcome back" is in order? :-)
Yes - first day back today. Lots of catching up to do.
> And apparently crash knows about poisoned pages and handles them: > > static int __init crash_save_vmcoreinfo_init(void) > { > ... > #ifdef CONFIG_MEMORY_FAILURE > VMCOREINFO_NUMBER(PG_hwpoison); > #endif > > so if that works, the kexeced kernel should know about that list.
Oh good ... it is smarter than I thought.
> Doesn't matter, right? The new copy is as clueless as the old one about > those MCEs.
If things are well enough initialized that we don't reset, and get to do_machine_check(), then this code from Ashok:
/* If this CPU is offline, just bail out. */ if (cpu_is_offline(smp_processor_id())) { u64 mcgstatus;
mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS); if (mcgstatus & MCG_STATUS_RIPV) { mce_wrmsrl(MSR_IA32_MCG_STATUS, 0); return; } }
will ignore the machine check on the other cpus ... assuming that "cpu_is_offline(smp_processor_id())" does the right thing in the kexec case where this is an "old" cpu that isn't online in the new kernel.
-Tony
| |