On Fri, Apr 20, 2018 at 12:37:08PM +0200, Borislav Petkov wrote: > Vitezslav reported a case where the > > "Timeout during microcode update!" > > panic would hit. After a deeper look, it turned out that his .config had > CONFIG_HOTPLUG_CPU disabled which practically made save_mc_for_early() a > no-op. > > When that happened, the discovered microcode patch wasn't saved into our > cache and the late loading path wouldn't find any. > > This, then, lead to early exit from __reload_late() and thus CPUs > waiting until the timeout is reached, leading to the panic. > > In hindsight, I should've made that function not return before the > post-synchronization. Oh well, I know better now... > > Reported-by: Vitezslav Samel <[email protected]> > Signed-off-by: Borislav Petkov <[email protected]>
Tested-by: Ashok Raj <[email protected]> > Cc: Ashok Raj <[email protected]> > Cc: <[email protected]> > Fixes: bb8c13d61a62 ("x86/microcode: Fix CPU synchronization routine") > Link: http://lkml.kernel.org/r/[email protected] > ---
