On 18. 01. 2023. 11:39, Das, Nirmoy wrote: >>> >>> Copying Mirsad who reported the issue in case he is still happy to give it >>> a quick test. Mirsad, I don't know if you are subscribed to one of the two >>> mailing lists where series was posted. In case not, you can grab both >>> patches from https://patchwork.freedesktop.org/series/112952/. >>> >>> Nirmoy - we also have an IGT written by Chuansheng - >>> https://patchwork.freedesktop.org/patch/515720/?series=101035&rev=4. A more >>> generic one could be placed in gem_mmap_offset test but this one works too >>> in my testing and is IMO better than nothing. >>> >>> Finally, let me add some tags below: >>> >>> On 17/01/2023 17:52, Nirmoy Das wrote: >>>> drm_vma_node_allow() and drm_vma_node_revoke() should be called in >>>> balanced pairs. We call drm_vma_node_allow() once per-file everytime a >>>> user calls mmap_offset, but only call drm_vma_node_revoke once per-file >>>> on each mmap_offset. As the mmap_offset is reused by the client, the >>>> per-file vm_count may remain non-zero and the rbtree leaked. >>>> >>>> Call drm_vma_node_allow_once() instead to prevent that memory leak. >>>> >>>> Cc: Tvrtko Ursulin <tvrtko.ursu...@linux.intel.com> >>>> Cc: Andi Shyti <andi.sh...@linux.intel.com> >>> >>> Fixes: 786555987207 ("drm/i915/gem: Store mmap_offsets in an rbtree rather >>> than a plain list") >>> Reported-by: Chuansheng Liu <chuansheng....@intel.com> >>> Reported-by: Mirsad Todorovac <mirsad.todoro...@alu.unizg.hr> >>> Cc: <sta...@vger.kernel.org> # v5.7+ >>> Reviewed-by: Tvrtko Ursulin <tvrtko.ursu...@intel.com> >>> >>> Regards, >>> >>> Tvrtko >>> >>>> >>>> Signed-off-by: Nirmoy Das <nirmoy....@intel.com> >>>> --- >>>> drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c >>>> b/drivers/gpu/drm/i915/gem/i915_gem_mman.c >>>> index 4f69bff63068..2aac6bf78740 100644 >>>> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c >>>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c >>>> @@ -697,7 +697,7 @@ mmap_offset_attach(struct drm_i915_gem_object *obj, >>>> GEM_BUG_ON(lookup_mmo(obj, mmap_type) != mmo); >>>> out: >>>> if (file) >>>> - drm_vma_node_allow(&mmo->vma_node, file); >>>> + drm_vma_node_allow_once(&mmo->vma_node, file); >>>> return mmo; >>>> err: >> >> The drm/i915 patch seems OK and there are currently no memory leaks as of >> reported by /sys/kernel/debug/kmemleak under the same Chrome load that >> triggered >> the initial bug ... > > > Thanks, Mirsad for quickly checking this!
P.S. Dear Nirmoy, To let me explain, as I work on the Academy of Fine Arts and the Faculty of Graphic Arts, video and multimedia drivers are of my special interest, so I kinda enjoyed this one. No need to thank. ;-) In case of more bugs discovered, I will be glad to test on my available platforms, considering it a part of my research. I can justify time spent on graphic and multimedia drivers, so it is not a big deal. Regards, Mirsad -- Mirsad Goran Todorovac Sistem inženjer Grafički fakultet | Akademija likovnih umjetnosti Sveučilište u Zagrebu System engineer Faculty of Graphic Arts | Academy of Fine Arts University of Zagreb, Republic of Croatia The European Union
