linux-kernel - Re: [PATCH 1/2] drm/amdgpu: Move racy global PMU list into device

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: <Y2sAucYLR4FsGIfc@google.com>
Date:   Tue, 8 Nov 2022 17:22:01 -0800
From:   Brian Norris <briannorris@...omium.org>
To:     Felix Kuehling <felix.kuehling@....com>
Cc:     Alex Deucher <alexander.deucher@....com>,
        Christian König <christian.koenig@....com>,
        Xinhui <Xinhui.Pan@....com>, amd-gfx@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org, dri-devel@...ts.freedesktop.org
Subject: Re: [PATCH 1/2] drm/amdgpu: Move racy global PMU list into device

On Tue, Nov 08, 2022 at 11:50:04AM -0500, Felix Kuehling wrote:
> While you're making the pmu list per-device, I'd suggest removing adev from
> the pmu entry because it is now redundant. The device is implied by the list
> that the entry is on. Instead, add an adev parameter to
> init_pmu_entry_by_type_and_add. Or you could move the list_add_tail to
> amdgpu_pmu_init and remove "_and_add" from the function name.

Sorry if I'm being naive here, but does that mean trying to navigate the
list pointers to move from a 'pmu_entry' to an 'adev'
(list_first_entry(), etc.)? There are quite a few cases where we're
trying to go between 'pmu_entry' and 'adev'. I guess I could turn that
into a mini helper.

I'll also need to scrounge around a bit to see if I have an amdgpu
system around that actually supports PMU. I realized the one I tested on
doesn't actually hit this code path... and this would be getting a
little less obvious/trivial.

> Other than that, the patch looks good to me.

Thanks for looking!

Brian