linux-kernel - Re: [PATCH 0/6] dma-fence: Remove return code of dma_fence

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <f74664fdf1cf0adba9a8b19b00db4823ee3f7f1b.camel@mailbox.org>
Date: Wed, 26 Nov 2025 15:09:26 +0100
From: Philipp Stanner <phasta@...lbox.org>
To: Christian König <christian.koenig@....com>, Philipp
 Stanner <phasta@...nel.org>, Sumit Semwal <sumit.semwal@...aro.org>,
 Gustavo Padovan <gustavo@...ovan.org>, Felix Kuehling
 <Felix.Kuehling@....com>, Alex Deucher <alexander.deucher@....com>, David
 Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, Jani Nikula
 <jani.nikula@...ux.intel.com>, Joonas Lahtinen
 <joonas.lahtinen@...ux.intel.com>, Rodrigo Vivi <rodrigo.vivi@...el.com>, 
 Tvrtko Ursulin <tursulin@...ulin.net>, Huang Rui <ray.huang@....com>,
 Matthew Auld <matthew.auld@...el.com>,  Matthew Brost
 <matthew.brost@...el.com>, Maarten Lankhorst
 <maarten.lankhorst@...ux.intel.com>, Maxime Ripard <mripard@...nel.org>,
 Thomas Zimmermann <tzimmermann@...e.de>, Lucas De Marchi
 <lucas.demarchi@...el.com>, Thomas Hellström
 <thomas.hellstrom@...ux.intel.com>
Cc: linux-media@...r.kernel.org, dri-devel@...ts.freedesktop.org, 
	linaro-mm-sig@...ts.linaro.org, linux-kernel@...r.kernel.org, 
	amd-gfx@...ts.freedesktop.org, intel-gfx@...ts.freedesktop.org, 
	intel-xe@...ts.freedesktop.org, rust-for-linux@...r.kernel.org
Subject: Re: [PATCH 0/6] dma-fence: Remove return code of dma_fence_signal()
 et al.

On Wed, 2025-11-26 at 15:02 +0100, Christian König wrote:
> On 11/26/25 14:19, Philipp Stanner wrote:
> > Barely anyone uses dma_fence_signal()'s (and similar functions') return
> > code. Checking it is pretty much useless anyways, because what are you
> > going to do if a fence was already signal it? Unsignal it and signal it
> > again? ;p
> 
> Reviewed-by: Christian König <christian.koenig@....com> for the entire series.
> 
> Please push to drm-misc-next or leave me a note when I should pick it up.

Thx! I can push it. Let's wait a while to see if some of the other
folks have sth to say.

> 
> > Removing the return code simplifies the API and makes it easier for me
> > to sit on top with Rust DmaFence.
> 
> BTW, I have an rb for embedding the lock and I'm now writing test cases.
> 
> When that is done you should be able to base the Rust DmaFence abstraction on that as well.

Yeah, thank you, that will actually help since I was in the process of
solving the same life time issues in Rust.

I will give your series a review ~tomorrow, too. Or should I wait for
v4 with the tests?

P.

> 
> Regards,
> Christian.
> 
> > 
> > Philipp Stanner (6):
> >   dma-buf/dma-fence: Add dma_fence_test_signaled_flag()
> >   amd/amdkfd: Ignore return code of dma_fence_signal()
> >   drm/gpu/xe: Ignore dma_fenc_signal() return code
> >   dma-buf: Don't misuse dma_fence_signal()
> >   drm/ttm: Remove return check of dma_fence_signal()
> >   dma-buf/dma-fence: Remove return code of signaling-functions
> > 
> >  drivers/dma-buf/dma-fence.c                   | 59 ++++++-------------
> >  drivers/dma-buf/st-dma-fence.c                |  7 +--
> >  drivers/gpu/drm/amd/amdkfd/kfd_process.c      |  5 +-
> >  .../gpu/drm/ttm/tests/ttm_bo_validate_test.c  |  3 +-
> >  drivers/gpu/drm/xe/xe_hw_fence.c              |  5 +-
> >  include/linux/dma-fence.h                     | 33 ++++++++---
> >  6 files changed, 53 insertions(+), 59 deletions(-)
> > 
>