Re: [PATCH] drm/radeon/ttm: Fix memory leak userptr pages

Felix Kuehling
2021-03-19T20:30:12Z

This caused a regression in kfdtest in a large-buffer stress test after
memory allocation for user pages fails:

[17359.536303] amdgpu: init_user_pages: Failed to get user pages: -16
[17359.543746] BUG: kernel NULL pointer dereference, address: 0000000000000000
[17359.551494] #PF: supervisor read access in kernel mode
[17359.557375] #PF: error_code(0x0000) - not-present page
[17359.563247] PGD 0 P4D 0
[17359.566514] Oops: 0000 [#1] SMP PTI
[17359.570728] CPU: 8 PID: 5944 Comm: kfdtest Not tainted 5.11.0-kfd-fkuehlin #193
[17359.578760] Hardware name: ASUS All Series/X99-E WS/USB 3.1, BIOS 3201 06/17/2016
[17359.586971] RIP: 0010:amdgpu_ttm_backend_unbind+0x52/0x110 [amdgpu]
[17359.594075] Code: 48 39 c6 74 1b 8b 53 0c 48 8d bd 80 a1 ff ff e8 24 62 00 00 85 c0 0f 85 ab 00 00 00 c6 43 54 00 5b 5d c3 48 8b 46 10 8b 4e 50 <48> 8b 30 48 85 f6 74 ba 8b 50 0c 48 8b bf 80 a1 ff ff 83 e1 01 45
[17359.614340] RSP: 0018:ffffa4764971fc98 EFLAGS: 00010206
[17359.620315] RAX: 0000000000000000 RBX: ffff950e8d4edf00 RCX: 0000000000000000
[17359.628204] RDX: 0000000000000000 RSI: ffff950e8d4edf00 RDI: ffff950eadec5e80
[17359.636084] RBP: ffff950eadec5e80 R08: 0000000000000000 R09: 0000000000000000
[17359.643958] R10: 0000000000000246 R11: 0000000000000001 R12: ffff950c03377800
[17359.651833] R13: ffff950eadec5e80 R14: ffff950c03377858 R15: 0000000000000000
[17359.659701] FS: 00007febb20cb740(0000) GS:ffff950ebfc00000(0000) knlGS:0000000000000000
[17359.668528] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[17359.675012] CR2: 0000000000000000 CR3: 00000006d700e005 CR4: 00000000001706e0
[17359.682883] Call Trace:
[17359.686063] amdgpu_ttm_backend_destroy+0x12/0x70 [amdgpu]
[17359.692349] ttm_bo_cleanup_memtype_use+0x37/0x60 [ttm]
[17359.698307] ttm_bo_release+0x278/0x5e0 [ttm]
[17359.703385] amdgpu_bo_unref+0x1a/0x30 [amdgpu]
[17359.708701] amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu+0x7e5/0x910 [amdgpu]
[17359.716307] kfd_ioctl_alloc_memory_of_gpu+0x11a/0x220 [amdgpu]
[17359.723036] kfd_ioctl+0x223/0x400 [amdgpu]
[17359.728017] ? kfd_dev_is_large_bar+0x90/0x90 [amdgpu]
[17359.734152] __x64_sys_ioctl+0x8b/0xd0
[17359.738796] do_syscall_64+0x2d/0x40
[17359.743259] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[17359.749205] RIP: 0033:0x7febb083b6d7
[17359.753681] Code: b3 66 90 48 8b 05 b1 47 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 47 2d 00 f7 d8 64 89 01 48
[17359.774340] RSP: 002b:00007ffdb5522cd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[17359.782668] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007febb083b6d7
[17359.790566] RDX: 00007ffdb5522d60 RSI: 00000000c0284b16 RDI: 0000000000000003
[17359.798459] RBP: 00007ffdb5522d10 R08: 00007ffdb5522dd0 R09: 00000000c4000004
[17359.806352] R10: 0000000000000000 R11: 0000000000000202 R12: 0000559416e4e2aa
[17359.814251] R13: 0000000000000000 R14: 0000000000000021 R15: 0000000000000000
[17359.822140] Modules linked in: ip6table_filter ip6_tables iptable_filter amdgpu x86_pkg_temp_thermal drm_ttm_helper ttm iommu_v2 gpu_sched ip_tables x_tables
[17359.837776] CR2: 0000000000000000
[17359.841888] ---[ end trace a6f27d64475b28c8 ]---
[17359.847318] RIP: 0010:amdgpu_ttm_backend_unbind+0x52/0x110 [amdgpu]
[17359.854479] Code: 48 39 c6 74 1b 8b 53 0c 48 8d bd 80 a1 ff ff e8 24 62 00 00 85 c0 0f 85 ab 00 00 00 c6 43 54 00 5b 5d c3 48 8b 46 10 8b 4e 50 <48> 8b 30 48 85 f6 74 ba 8b 50 0c 48 8b bf 80 a1 ff ff 83 e1 01 45
[17359.874929] RSP: 0018:ffffa4764971fc98 EFLAGS: 00010206
[17359.881014] RAX: 0000000000000000 RBX: ffff950e8d4edf00 RCX: 0000000000000000
[17359.889007] RDX: 0000000000000000 RSI: ffff950e8d4edf00 RDI: ffff950eadec5e80
[17359.897008] RBP: ffff950eadec5e80 R08: 0000000000000000 R09: 0000000000000000
[17359.905020] R10: 0000000000000246 R11: 0000000000000001 R12: ffff950c03377800
[17359.913034] R13: ffff950eadec5e80 R14: ffff950c03377858 R15: 0000000000000000
[17359.921050] FS: 00007febb20cb740(0000) GS:ffff950ebfc00000(0000) knlGS:0000000000000000
[17359.930047] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[17359.936674] CR2: 0000000000000000 CR3: 00000006d700e005 CR4: 00000000001706e0

Reverting this patch fixes the problem for me.

Regards,
Felix

On 2021-03-18 10:57 p.m., Alex Deucher wrote:
> Applied. Thanks!
>
> Alex
>
> On Thu, Mar 18, 2021 at 5:00 AM Koenig, Christian
> <Christian.Koenig@amd.com> wrote:
>> Reviewed-by: Christian König <christian.koenig@amd.com>
>> ________________________________
>> Von: Daniel Gomez <daniel@qtec.com>
>> Gesendet: Donnerstag, 18. März 2021 09:32
>> Cc: dagmcr@gmail.com <dagmcr@gmail.com>; Daniel Gomez <daniel@qtec.com>; Deucher, Alexander <Alexander.Deucher@amd.com>; Koenig, Christian <Christian.Koenig@amd.com>; David Airlie <airlied@linux.ie>; Daniel Vetter <daniel@ffwll.ch>; amd-gfx@lists.freedesktop.org <amd-gfx@lists.freedesktop.org>; dri-devel@lists.freedesktop.org <dri-devel@lists.freedesktop.org>; linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>
>> Betreff: [PATCH] drm/radeon/ttm: Fix memory leak userptr pages
>>
>> If userptr pages have been pinned but not bounded,
>> they remain uncleared.
>>
>> Signed-off-by: Daniel Gomez <daniel@qtec.com>
>> ---
>> drivers/gpu/drm/radeon/radeon_ttm.c | 5 +++--
>> 1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
>> index e8c66d10478f..bbcc6264d48f 100644
>> --- a/drivers/gpu/drm/radeon/radeon_ttm.c
>> +++ b/drivers/gpu/drm/radeon/radeon_ttm.c
>> @@ -485,13 +485,14 @@ static void radeon_ttm_backend_unbind(struct ttm_bo_device *bdev, struct ttm_tt
>> struct radeon_ttm_tt *gtt = (void *)ttm;
>> struct radeon_device *rdev = radeon_get_rdev(bdev);
>>
>> + if (gtt->userptr)
>> + radeon_ttm_tt_unpin_userptr(bdev, ttm);
>> +
>> if (!gtt->bound)
>> return;
>>
>> radeon_gart_unbind(rdev, gtt->offset, ttm->num_pages);
>>
>> - if (gtt->userptr)
>> - radeon_ttm_tt_unpin_userptr(bdev, ttm);
>> gtt->bound = false;
>> }
>>
>> --
>> 2.30.2
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel