Re: [PATCH] efi/capsule: Make efi_capsule_pending() lockless

From: Matt Fleming
Date: Wed May 04 2016 - 09:37:07 EST

On Wed, 04 May, at 02:20:42PM, Borislav Petkov wrote:
> On Wed, May 04, 2016 at 12:46:05PM +0100, Matt Fleming wrote:
> > But emergency_restart() is called after bust_spinlocks(0) which can
> > reset oops_in_progress, so can't even use that to solve the panic
> > case.
> Blergh.
> So I guess you need an explicit call efi_stop_capsules() somewhere in
> the reboot path and be done with it. No reboot notifiers, no bla bla.
> Just one big hammer which STFU the EFI.

But you can't block in the reboot path and you can't guarantee you'll
interrupt an in-progress EFI capsule update call that started before
you entered the reboot path.