Hi guys,
yes Yintian is right this is essentially the same lock just different
pointers to it.
Looks like that Coverity is not doing an alias analyses to figure out if
two pointer point to the same thing.
On the other hand we could probably use the same pointer in the code for
both locking and unlocking.
Regards,
Christian.
Am 25.04.20 um 08:46 schrieb Tao, Yintian:
Hi
This is a false positive. Please have a look at the code, here &kiq->ring_lock is equal to &adev->gfx.kiq.ring_lock
Because kiq is fetched from adev->gfx.kiq. These two expressions are equivalent.
Best Regards
Yintian Tao
-----Original Message-----
From: coverity-bot <keescook@xxxxxxxxxxxx>
Sent: 2020年4月24日 23:26
To: Tao, Yintian <Yintian.Tao@xxxxxxx>
Cc: Koenig, Christian <Christian.Koenig@xxxxxxx>; Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>; linux-next@xxxxxxxxxxxxxxx
Subject: Coverity: gmc_v10_0_flush_gpu_tlb_pasid(): Program hangs
Hello!
This is an experimental semi-automated report about issues detected by Coverity from a scan of next-20200424 as part of the linux-next scan project:
https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fscan.coverity.com%2Fprojects%2Flinux-next-weekly-scan&data=02%7C01%7CYintian.Tao%40amd.com%7Cb4e164ff3f1542f14c2008d7e863dae8%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637233387886678181&sdata=QyZO8PdGBQF6NrWhXb1Ym0aoQhzotuCzwT3M1TwYQfk%3D&reserved=0
You're getting this email because you were associated with the identified lines of code (noted below) that were touched by commits:
Thu Apr 23 12:05:54 2020 +0800
82478876eaac ("drm/amdgpu: protect ring overrun")
Coverity reported the following:
*** CID 1492715: Program hangs (LOCK)
/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c: 434 in gmc_v10_0_flush_gpu_tlb_pasid()
428 kiq->pmf->kiq_invalidate_tlbs(ring,
429 pasid, flush_type, all_hub);
430 r = amdgpu_fence_emit_polling(ring, &seq, MAX_KIQ_REG_WAIT);
431 if (r) {
432 amdgpu_ring_undo(ring);
433 spin_unlock(&kiq->ring_lock);
vvv CID 1492715: Program hangs (LOCK)
vvv Returning without unlocking "adev->gfx.kiq.ring_lock".
434 return -ETIME;
435 }
436
437 amdgpu_ring_commit(ring);
438 spin_unlock(&adev->gfx.kiq.ring_lock);
439 r = amdgpu_fence_wait_polling(ring, seq, adev->usec_timeout);
If this is a false positive, please let us know so we can mark it as such, or teach the Coverity rules to be smarter. If not, please make sure fixes get into linux-next. :) For patches fixing this, please include these lines (but double-check the "Fixes" first):
Reported-by: coverity-bot <keescook+coverity-bot@xxxxxxxxxxxx>
Addresses-Coverity-ID: 1492715 ("Program hangs")
Fixes: 82478876eaac ("drm/amdgpu: protect ring overrun")
Thanks for your attention!
--
Coverity-bot
