Re: [PATCH] drm/amdgpu: don't attach the tlb fence for SI

["Viktor Jägersküpper" <viktor_jaegerskuepper@freenet.de>]

(Adding Sasha to this thread)

Hans de Goede wrote:
> Hi Greg,
> 
> On 15-Dec-25 10:05 AM, Greg KH wrote:
>> On Mon, Dec 15, 2025 at 09:15:17AM +0100, Hans de Goede wrote:
>>> Hi greg,
>>>
>>> On 15-Dec-25 9:12 AM, Greg KH wrote:
>>>> On Sun, Dec 14, 2025 at 10:53:36AM +0100, Hans de Goede wrote:
>>>>> From: Alex Deucher <alexander.deucher@amd.com>
>>>>>
>>>>> commit eb296c09805ee37dd4ea520a7fb3ec157c31090f upstream.
>>>>>
>>>>> SI hardware doesn't support pasids, user mode queues, or
>>>>> KIQ/MES so there is no need for this.  Doing so results in
>>>>> a segfault as these callbacks are non-existent for SI.
>>>>>
>>>>> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4744
>>>>> Fixes: f3854e04b708 ("drm/amdgpu: attach tlb fence to the PTs update")
>>>>> Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
>>>>> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
>>>>> Signed-off-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
>>>>> ---
>>>>>  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 4 +++-
>>>>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>>>
>>>> What kernel tree(s) should this go to?
>>>
>>> This fixes a regression introduced in at least 6.17.y (6.17.11)
>>> and 6.18.y (6.18.1). So it should at least go to those branches.
>>
>> But that commit is in 6.19-rc1, not anything older.
>>
>>> If any other branches also have gotten commit f3854e04b708
>>> backported then those should get this too.
>>
>> I don't see that commit in any stable tree, what am I missing?
> 
> Ah, I see now the Fixes tag in the original fix (which I cherry
> picked) is wrong and does not point to the canonical commit id as
> merged into Torvalds tree, sorry.
> 
> This is b4a7f4e7ad2b120a94f3111f92a11520052c762d  ("drm/amdgpu:
> attach tlb fence to the PTs update") in Torvalds' tree:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b4a7f4e7ad2b120a94f3111f92a11520052c762d
> 
> and this actually made it into the v6.18 tag (vs being introduced
> in 6.18.1 as I originally thought).
> 
> This is also in 6.17.11 as 23316ed02c228b52f871050f98a155f3d566c450
> 
> https://web.git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/drivers/gpu/drm/amd?h=linux-6.17.y&id=23316ed02c228b52f871050f98a155f3d566c450
> 
> FWIW I don't see it in 6.12.y (and I did not look further back).
> 
> Regards,
> 
> Hans
Can this fix be added to the 6.18 queue, please? All relevant
information can be found in the previous email from Hans.

Thanks,
Viktor