Re: [edk2-devel] [PATCH v3 0/4] ArmPkg/SecurityPkg: Fixes for ArmTrngLib/RngDxe

["Ard Biesheuvel" <ardb@kernel.org>]

On Mon, 6 Mar 2023 at 16:42, Yao, Jiewen <jiewen.yao@intel.com> wrote:
>
> Hi Pierre
> I don’t have strong opinion.
>
> For ARM specific patch, would you please get R-B from ARM expert?
>
> I think we need to wait for the response from Ard to confirm.
>

These patches

  SecurityPkg/RngDxe: Correctly update mAvailableAlgoArrayCount
  SecurityPkg/RngDxe: Conditionally install EFI_RNG_PROTOCOL

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>

Jiewen, if you don't mind, I will merge those right away.

For the remaining patch, I am not sure I understand why the behavior
regarding the zero GUID is correct. Perhaps we could
revisit/resend/review that patch in isolation?

Thanks,
Ard.




>
> > -----Original Message-----
> > From: Pierre Gondois <pierre.gondois@arm.com>
> > Sent: Monday, March 6, 2023 11:38 PM
> > To: devel@edk2.groups.io
> > Cc: Leif Lindholm <leif@nuviainc.com>; Sami Mujawar
> > <sami.mujawar@arm.com>; Yao, Jiewen <jiewen.yao@intel.com>; Wang,
> > Jian J <jian.j.wang@intel.com>; Ard Biesheuvel <ardb@kernel.org>
> > Subject: Re: [edk2-devel] [PATCH v3 0/4] ArmPkg/SecurityPkg: Fixes for
> > ArmTrngLib/RngDxe
> >
> > Hello Jiewen, Jian,
> > Do these patches in this set look ok to you ?
> > - SecurityPkg/RngDxe: Correctly update mAvailableAlgoArrayCount
> > - SecurityPkg/RngDxe: Conditionally install EFI_RNG_PROTOCOL
> > - SecurityPkg/RngDxe: Fix Rng algo selection for Arm
> >
> > Regards,
> > Pierre
> >
> > On 2/10/23 10:26, PierreGondois via groups.io wrote:
> > > Hello Jiewen, Jian,
> > > Just a reminder in case this was forgotten,
> > > Regards,
> > > Pierre
> > >
> > > On 1/9/23 13:26, Pierre Gondois wrote:
> > >> Hello,
> > >> I was wondering if I should re-arrange the patch in any way/there was any
> > >> concern with the patch set. The first patch of serie was taken, but the
> > other
> > >> ones are pending,
> > >>
> > >> Regards,
> > >> Pierre
> > >>
> > >> On 11/28/22 14:34, PierreGondois via groups.io wrote:
> > >>> Hello Ard,
> > >>>
> > >>> On 11/26/22 15:33, Ard Biesheuvel wrote:
> > >>>> On Thu, 24 Nov 2022 at 17:18, <Pierre.Gondois@arm.com> wrote:
> > >>>>>
> > >>>>> From: Pierre Gondois <pierre.gondois@arm.com>
> > >>>>>
> > >>>>> v1:
> > >>>>> - https://edk2.groups.io/g/devel/message/96356
> > >>>>> v2:
> > >>>>> - https://edk2.groups.io/g/devel/message/96434
> > >>>>> - Reformulate commit message.
> > >>>>> - Do not warn if no algorithm is found as the message
> > >>>>>       would be printed on non-Arm platforms.
> > >>>>> v3:
> > >>>>> - Add the following patches:
> > >>>>>       1. ArmPkg/ArmTrngLib: Remove ASSERTs in
> > ArmTrngLibConstructor()
> > >>>>>          Requested by Ard.
> > >>>>>          Cf https://edk2.groups.io/g/devel/message/96495
> > >>>>>       2. SecurityPkg/RngDxe: Conditionally install EFI_RNG_PROTOCOL
> > >>>>>          Do not install EFI_RNG_PROTOCOL if no RNG algorithm is
> > available.
> > >>>>>          Cf. https://edk2.groups.io/g/devel/message/96494
> > >>>>>       3. SecurityPkg/RngDxe: Fix Rng algo selection for Arm
> > >>>>>          Coming from v2 patch being split.
> > >>>>>
> > >>>>> Some issues were found by Ard/Sami on the RngDxe/ArmTrngLib after
> > >>>>> recent patches were merged. This patch serie intends to fix them.
> > >>>>>
> > >>>>> Pierre Gondois (4):
> > >>>>>       ArmPkg/ArmTrngLib: Remove ASSERTs in ArmTrngLibConstructor()
> > >>>>
> > >>>> Thanks for the fixed
> > >>>>
> > >>>> Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
> > >>>>
> > >>>> I pushed this one as #3663 (pending CI verification atm)
> > >>>>
> > >>>>>       SecurityPkg/RngDxe: Correctly update mAvailableAlgoArrayCount
> > >>>>>       SecurityPkg/RngDxe: Conditionally install EFI_RNG_PROTOCOL
> > >>>>>       SecurityPkg/RngDxe: Fix Rng algo selection for Arm
> > >>>>>
> > >>>>
> > >>>> The remaining code still looks a bit clunky to me. Can't we just
> > >>>> return an error from the library constructor of the library cannot
> > >>>> initialize due to a missing prerequisite?
> > >>>
> > >>> In RngDriverEntry(), GetAvailableAlgorithms() probe the available
> > >>> RNG algorithms. If there are none, then we return an error code.
> > >>> Otherwise we install EFI_RNG_PROTOCOL.
> > >>>
> > >>> I assume the prerequisite you a referring to is 'checking there is
> > >>> at least one available RNG algorithm that RngDxe can use', so if
> > >>> ArmTrngLib's constructor fails, we should not prevent RngDxe to be
> > >>> loaded (as the RngLib could be used for instance).
> > >>>
> > >>> Does it answer your question, or did I understand it incorrectly ?
> > >>>
> > >>> Regards,
> > >>> Pierre
> > >>>
> > >>>>
> > >>>>
> > >>>>>      ArmPkg/Library/ArmTrngLib/ArmTrngLib.c        |  5 -----
> > >>>>>      .../RandomNumberGenerator/RngDxe/ArmRngDxe.c  | 18 +++++---
> > ----------
> > >>>>>      .../RngDxe/Rand/RngDxe.c                      |  9 ++++++++-
> > >>>>>      .../RandomNumberGenerator/RngDxe/RngDxe.c     | 19
> > ++++++++++++++-----
> > >>>>>      4 files changed, 27 insertions(+), 24 deletions(-)
> > >>>>>
> > >>>>> --
> > >>>>> 2.25.1
> > >>>>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >>>
> > >
> > >
> > > 
> > >
> > >