[PATCH] Revert "drm/amdgpu: init iommu after amdkfd device init"

[Armin Wolf]

Am 04.06.24 um 20:28 schrieb Deucher, Alexander:

> [AMD Official Use Only - AMD Internal Distribution Only]
>
>> -----Original Message-----
>> From: Kuehling, Felix <Felix.Kuehling at amd.com>
>> Sent: Tuesday, June 4, 2024 2:25 PM
>> To: Armin Wolf <W_Armin at gmx.de>; Deucher, Alexander
>> <Alexander.Deucher at amd.com>; Koenig, Christian
>> <Christian.Koenig at amd.com>; Pan, Xinhui <Xinhui.Pan at amd.com>;
>> gregkh at linuxfoundation.org; sashal at kernel.org
>> Cc: stable at vger.kernel.org; bkauler at gmail.com; Zhang, Yifan
>> <Yifan1.Zhang at amd.com>; Liang, Prike <Prike.Liang at amd.com>; dri-
>> devel at lists.freedesktop.org; amd-gfx at lists.freedesktop.org
>> Subject: Re: [PATCH] Revert "drm/amdgpu: init iommu after amdkfd device
>> init"
>>
>>
>> On 2024-06-03 18:19, Armin Wolf wrote:
>>> Am 23.05.24 um 19:30 schrieb Armin Wolf:
>>>
>>>> This reverts commit 56b522f4668167096a50c39446d6263c96219f5f.
>>>>
>>>> A user reported that this commit breaks the integrated gpu of his
>>>> notebook, causing a black screen. He was able to bisect the
>>>> problematic commit and verified that by reverting it the notebook works
>> again.
>>>> He also confirmed that kernel 6.8.1 also works on his device, so the
>>>> upstream commit itself seems to be ok.
>>>>
>>>> An amdgpu developer (Alex Deucher) confirmed that this patch should
>>>> have never been ported to 5.15 in the first place, so revert this
>>>> commit from the 5.15 stable series.
>>> Hi,
>>>
>>> what is the status of this?
>> Which branch is this for? This patch won't apply to anything after Linux 6.5.
> It's applicable to 5.15 stable only.  The original patch caused a regression on 5.15 so probably should not have been applied there.
>
> Alex
>
Correct, and i would be very grateful if this regression could be resolved in the near future.
The user already wrote a blog post about the whole issue, see here:

https://bkhome.org/news/202405/kernel-amd-gpu-disaster-fixed.html

Thanks,
Armin Wolf

>> Support for IOMMUv2 was removed from amdgpu in Linux 6.6 by:
>>
>> commit c99a2e7ae291e5b19b60443eb6397320ef9e8571
>> Author: Alex Deucher <alexander.deucher at amd.com>
>> Date:   Fri Jul 28 12:20:12 2023 -0400
>>
>>       drm/amdkfd: drop IOMMUv2 support
>>
>>       Now that we use the dGPU path for all APUs, drop the
>>       IOMMUv2 support.
>>
>>       v2: drop the now unused queue manager functions for gfx7/8 APUs
>>
>>       Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com>
>>       Acked-by: Christian König <christian.koenig at amd.com>
>>       Tested-by: Mike Lothian <mike at fireburn.co.uk>
>>       Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
>>
>> Regards,
>>     Felix
>>
>>
>>> Armin Wolf
>>>
>>>> Reported-by: Barry Kauler <bkauler at gmail.com>
>>>> Signed-off-by: Armin Wolf <W_Armin at gmx.de>
>>>> ---
>>>>    drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 8 ++++----
>>>>    1 file changed, 4 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> index 222a1d9ecf16..5f6c32ec674d 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>>> @@ -2487,6 +2487,10 @@ static int amdgpu_device_ip_init(struct
>>>> amdgpu_device *adev)
>>>>        if (r)
>>>>            goto init_failed;
>>>>
>>>> +    r = amdgpu_amdkfd_resume_iommu(adev);
>>>> +    if (r)
>>>> +        goto init_failed;
>>>> +
>>>>        r = amdgpu_device_ip_hw_init_phase1(adev);
>>>>        if (r)
>>>>            goto init_failed;
>>>> @@ -2525,10 +2529,6 @@ static int amdgpu_device_ip_init(struct
>>>> amdgpu_device *adev)
>>>>        if (!adev->gmc.xgmi.pending_reset)
>>>>            amdgpu_amdkfd_device_init(adev);
>>>>
>>>> -    r = amdgpu_amdkfd_resume_iommu(adev);
>>>> -    if (r)
>>>> -        goto init_failed;
>>>> -
>>>>        amdgpu_fru_get_product_info(adev);
>>>>
>>>>    init_failed:
>>>> --
>>>> 2.39.2
>>>>
>>>>