On 22.09.25 15:42, Melissa Wen wrote: > On 22/09/2025 08:54, Thomas Zimmermann wrote: >> Hi Melissa >> >> Am 19.09.25 um 17:54 schrieb Melissa Wen: >>> Hi all, >>> >>> I just talked with Thomas that these two patches are preventing amdgpu >>> driver to be unloaded: >>> >>> `modprobe: FATAL: Module amdgpu is in use.` >>> >>> and there is no process using the driver. >> >> What's the exact STR for this problem? After Christian's comments, I tried >> to reproduce the issue, but it works on my system. I do >> >> - boot up with amdgpu in text mode (multiuser.target) >> - login by serial console >> - 'rmmod amdgpu' >> >> That last step turns my test system's display off and unloads amdgpu. The >> kernel is a recent drm-tip at v6.17-rc6. > > - I booted up in graphical.target; > - Connected via ssh, dropped the graphical interface to text mode > (multiuser.target), and tried to remove the module with `modprobe -r amdgpu` > > The issue happened in the latest 6.16 kernel version from Debian (I don't > have the machine with me atm to check the exact version), but also with > mainline kernel from last week. > > I bisected kernel from 6.16 and 6.15 and IIRC git bisect pointed to > `drm/framebuffer: Acquire internal references on GEM handles`, but as it > triggers another trace and AFAIU fixes `drm/gem: Acquire references on GEM > handles for framebuffers`, I reverted both pacthes and amdgpu loaded/unloaded > as expected. > > IGT amdgpu-specific tests for loading and unloading are also failing because > it's not able to unload the module. > I didn't run the generic test. > > I'm using an AMD Cezanne laptop with a touch-screen capable display (hp envy > x360 convertible) with Debian + Gnome. > I looked for process using the modules, but I didn't find any. > > BTW, I don't discard that this work uncovered a preexist problem, for example. > Since those patches are addressing other issues, as mentioned by Maarten, > I'll debug the amdgpu driver further and check the points raised.
Well could it be that the graphics target left a CRTC running and a framebuffer being scanned out? Regards, Christian. > > Best Regards, > > Melissa > >> >> Best regards >> Thomas >> >>> >>> We agreed that the best approach now is to completely revert the work >>> done for improving DMA bug handling to avoid any loose ends. With these >>> reverts we are just back to the old behavior and amdgpu loading and >>> unloading will return to normal. >>> >>> Best Regards, >>> >>> Melissa >>> >>> Melissa Wen (2): >>> Revert "drm/framebuffer: Acquire internal references on GEM handles" >>> Revert "drm/gem: Acquire references on GEM handles for framebuffers" >>> >>> drivers/gpu/drm/drm_framebuffer.c | 31 +-------------- >>> drivers/gpu/drm/drm_gem.c | 64 +++++-------------------------- >>> drivers/gpu/drm/drm_internal.h | 2 - >>> include/drm/drm_framebuffer.h | 7 ---- >>> 4 files changed, 11 insertions(+), 93 deletions(-) >>> >> >
