linux-kernel - RFC: How to adjust the trace pid?

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-next>] [day] [month] [year] [list]

Message-Id: <20200807133658.1866-1-christian.koenig@amd.com>
Date:   Fri,  7 Aug 2020 15:36:57 +0200
From:   "Christian König" 
        <ckoenig.leichtzumerken@...il.com>
To:     amd-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org
Cc:     Shashank.Sharma@....com, daniel.vetter@...ll.ch,
        alexander.deucher@....com
Subject: RFC: How to adjust the trace pid?

Hi everybody,

in amdgpu we got the following issue which I'm seeking advise how to cleanly handle it.

We have a bunch of trace points which are related to the VM subsystem and executed in either a work item, kthread or foreign process context.

Now tracing the pid of the context which we are executing in is not really that useful, so I'm wondering if we could just overwrite the pid recorded in the trace entry?

The following patch does exactly that for the vm_grab_id() trace point, but I'm not 100% sure if that is legal or not.

Any ideas? Comments?

Thanks,
Christian.