Re: [PATCH] drm/amdgpu: Fix validating flush_gpu_tlb_pasid()

["Timur Kristóf" <timur.kristof@gmail.com>]

On Monday, January 19, 2026 6:27:10 AM Central European Standard Time Liang, 
Prike wrote:
> [Public]
> 
> In order to avoid being blocked by the lock issue on some older GFX, I will
> push the patch to amd-staging-drm-next.
> If you have any concerns, please
> let me know.
> 

Hi Prike,

Thank you, feel free to add the necessary tags and push the patch.

Best regards,
Timur

> 
> 
> > -----Original Message-----
> > From: amd-gfx <amd-gfx-bounces@lists.freedesktop.org> On Behalf Of Liang,
> > Prike
 Sent: Monday, January 19, 2026 9:58 AM
> > To: Timur Kristóf <timur.kristof@gmail.com>;
> > amd-gfx@lists.freedesktop.org;
 Deucher, Alexander
> > <Alexander.Deucher@amd.com>; Koenig, Christian
> > <Christian.Koenig@amd.com>; Limonciello, Mario
> > <Mario.Limonciello@amd.com>; Dan Carpenter <dan.carpenter@linaro.org>
> > Subject: RE: [PATCH] drm/amdgpu: Fix validating flush_gpu_tlb_pasid()
> >
> >
> >
> > [Public]
> >
> >
> >
> > Thank you for the fix. Could you please add the following the tags?
> >
> >
> >
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> > | Closes: https://lore.kernel.org/r/202601190121.z9C0uml5-lkp@intel.com/
> >
> >
> >
> > Reviewed-by: Prike Liang <Prike.Liang@amd.com>
> >
> >
> >
> > Regards,
> > 
> >       Prike
> >
> >
> >
> > > -----Original Message-----
> > > From: Timur Kristóf <timur.kristof@gmail.com>
> > > Sent: Sunday, January 18, 2026 8:58 PM
> > > To: amd-gfx@lists.freedesktop.org; Deucher, Alexander
> > > <Alexander.Deucher@amd.com>; Koenig, Christian
> > > <Christian.Koenig@amd.com>; Liang, Prike <Prike.Liang@amd.com>;
> > > Limonciello, Mario <Mario.Limonciello@amd.com>
> > > Cc: Timur Kristóf <timur.kristof@gmail.com>
> > > Subject: [PATCH] drm/amdgpu: Fix validating flush_gpu_tlb_pasid()
> > >
> > >
> > >
> > > When a function holds a lock and we return without unlocking it, it
> > > deadlocks the kernel. We should always unlock before returning.
> > >
> > >
> > >
> > > This commit fixes suspend/resume on SI.
> > > Tested on two Tahiti GPUs: FirePro W9000 and R9 280X.
> > >
> > >
> > >
> > > Fixes: bc2dea30038a ("drm/amdgpu: validate the flush_gpu_tlb_pasid()")
> > > Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
> > > ---
> > > 
> > >  drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 5 ++---
> > >  1 file changed, 2 insertions(+), 3 deletions(-)
> > >
> > >
> > >
> > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> > > b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> > > index 0e67fa4338ff..4fa24be1bf45 100644
> > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
> > > @@ -769,7 +769,7 @@ int amdgpu_gmc_flush_gpu_tlb_pasid(struct
> > > amdgpu_device *adev, uint16_t pasid,
> > > 
> > >       struct amdgpu_ring *ring = &adev->gfx.kiq[inst].ring;
> > >       struct amdgpu_kiq *kiq = &adev->gfx.kiq[inst];
> > >       unsigned int ndw;
> > > 
> > > -     int r, cnt = 0;
> > > +     int r = 0, cnt = 0;
> > > 
> > >       uint32_t seq;
> > >
> > >
> > >
> > >       /*
> > > 
> > > @@ -782,7 +782,7 @@ int amdgpu_gmc_flush_gpu_tlb_pasid(struct
> > > amdgpu_device *adev, uint16_t pasid,
> > > 
> > >       if (!adev->gmc.flush_pasid_uses_kiq || !ring->sched.ready) {
> > >
> > >
> > >
> > >               if (!adev->gmc.gmc_funcs->flush_gpu_tlb_pasid)
> > > 
> > > -                     return 0;
> > > +                     goto error_unlock_reset;
> > >
> > >
> > >
> > >               if (adev->gmc.flush_tlb_needs_extra_type_2)
> > >               
> > >                       adev->gmc.gmc_funcs->flush_gpu_tlb_pasid(adev,
> > > 
> > > pasid, @@ -797,7 +797,6 @@ int amdgpu_gmc_flush_gpu_tlb_pasid(struct
> > > amdgpu_device *adev, uint16_t pasid,
> > > 
> > >               adev->gmc.gmc_funcs->flush_gpu_tlb_pasid(adev, pasid,
> > >               
> > >                                                        flush_type,
> > >                                                        all_hub,
> > >                                                        inst);
> > > 
> > > -             r = 0;
> > > 
> > >       } else {
> > >       
> > >               /* 2 dwords flush + 8 dwords fence */
> > >               ndw = kiq->pmf->invalidate_tlbs_size + 8;
> > > 
> > > --
> > > 2.52.0
> 
>