On 03/02/2015 11:32 AM, Borislav Petkov wrote: > On Mon, Mar 02, 2015 at 11:33:33PM +0900, Naoya Horiguchi wrote: >> Yes, CPU offlining is one option to keep other CPUs quiet. I'm not sure why >> current kexec implementation doesn't offline the other CPUs but just doing >> cpu_relax() loop, but my guess is that in some kernel panic situation (like >> soft lockup) we want to keep CPUs' status undisturbed to make sure the bug's >> info is captured in kdump. > > Well either offlining or keeping them in the idle loop is fine - they're > not executing anything else and thus the probability of them causing an > MCE becomes disappearingly small.
Unless entering a deep C state kicks an MCE ... which we've seen with flaky hardware. P. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
