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

From: Kweh, Hock Leong
Date: Thu May 05 2016 - 10:27:37 EST

> -----Original Message-----
> From: Matt Fleming [mailto:matt@xxxxxxxxxxxxxxxxxxx]
> Sent: Wednesday, May 04, 2016 10:36 PM
> To: Kweh, Hock Leong; Bryan O'Donoghue
> Cc: linux-efi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Ard Biesheuvel;
> joeyli; Borislav Petkov
> Subject: Re: [PATCH] efi/capsule: Make efi_capsule_pending() lockless
> On Wed, 04 May, at 02:20:42PM, Borislav Petkov wrote:
> >
> > Blergh.
> Wilson, Bryan, what kind of rollback support does the Intel Quark have if its
> firmware update is interrupted?
> The interruption could be for a number of reasons including power loss, or
> the example in this case, rebooting due to panic().

If not mistaken, the EFI firmware will not update a partially uploaded binary due to checksum error.
User is required to re-update the efi capsule again on the next boot up.