kernel.git/drivers/gpu/drm/scheduler, branch linux-5.5.y

drm/scheduler: fix rare NULL ptr race

2020-04-17T14:11:50Z

[ Upstream commit 3c0fdf3302cb4f186c871684eac5c407a107e480 ] There is one one corner case at dma_fence_signal_locked which will raise the NULL pointer problem just like below. ->dma_fence_signal ->dma_fence_signal_locked ->test_and_set_bit here trigger dma_fence_release happen due to the zero of fence refcount. ->dma_fence_put ->dma_fence_release ->drm_sched_fence_release_scheduled ->call_rcu here make the union fled “cb_list” at finished fence to NULL because struct rcu_head contains two pointer which is same as struct list_head cb_list Therefore, to hold the reference of finished fence at drm_sched_process_job to prevent the null pointer during finished fence dma_fence_signal [ 732.912867] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 732.914815] #PF: supervisor write access in kernel mode [ 732.915731] #PF: error_code(0x0002) - not-present page [ 732.916621] PGD 0 P4D 0 [ 732.917072] Oops: 0002 [#1] SMP PTI [ 732.917682] CPU: 7 PID: 0 Comm: swapper/7 Tainted: G OE 5.4.0-rc7 #1 [ 732.918980] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 [ 732.920906] RIP: 0010:dma_fence_signal_locked+0x3e/0x100 [ 732.938569] Call Trace: [ 732.939003] [ 732.939364] dma_fence_signal+0x29/0x50 [ 732.940036] drm_sched_fence_finished+0x12/0x20 [gpu_sched] [ 732.940996] drm_sched_process_job+0x34/0xa0 [gpu_sched] [ 732.941910] dma_fence_signal_locked+0x85/0x100 [ 732.942692] dma_fence_signal+0x29/0x50 [ 732.943457] amdgpu_fence_process+0x99/0x120 [amdgpu] [ 732.944393] sdma_v4_0_process_trap_irq+0x81/0xa0 [amdgpu] v2: hold the finished fence at drm_sched_process_job instead of amdgpu_fence_process v3: resume the blank line Signed-off-by: Yintian Tao Reviewed-by: Christian König Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin

drm/sched: Avoid job cleanup if sched thread is parked.

2019-11-07T23:08:07Z

When the sched thread is parked we assume ring_mirror_list is not accessed from here. Signed-off-by: Andrey Grodzovsky Reviewed-by: Christian König Signed-off-by: Alex Deucher

drm/sched: Use completion to wait for sched->thread idle v2.

2019-11-07T23:08:07Z

Removes thread park/unpark hack from drm_sched_entity_fini and by this fixes reactivation of scheduler thread while the thread is supposed to be stopped. v2: Per sched entity completion. Signed-off-by: Andrey Grodzovsky Suggested-by: Christian König Reviewed-by: Christian König Signed-off-by: Alex Deucher

drm/sched: Fix passing zero to 'PTR_ERR' warning v2

2019-11-06T21:27:47Z

Fix a static code checker warning. v2: Drop PTR_ERR_OR_ZERO. Signed-off-by: Andrey Grodzovsky Reviewed-by: Emily Deng Reviewed-by: Christian König Signed-off-by: Alex Deucher

Merge tag 'drm-next-5.5-2019-11-01' of git://people.freedesktop.org/~agd5f/linux into drm-next

2019-11-04T00:22:53Z

drm-next-5.5-2019-11-01: amdgpu: - Add EEPROM support for Arcturus - Enable VCN encode support for Arcturus - Misc PSP fixes - Misc DC fixes - swSMU cleanup amdkfd: - Misc cleanups - Fix typo in cu bitmap parsing Signed-off-by: Dave Airlie From: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20191101190607.3763-1-alexander.deucher@amd.com

drm/sched: Set error to s_fence if HW job submission failed.

2019-10-25T20:50:11Z

Problem: When run_job fails and HW fence returned is NULL we still signal the s_fence to avoid hangs but the user has no way of knowing if the actual HW job was ran and finished. Fix: Allow .run_job implementations to return ERR_PTR in the fence pointer returned and then set this error for s_fence->finished fence so whoever wait on this fence can inspect the signaled fence for an error. Signed-off-by: Andrey Grodzovsky Reviewed-by: Christian König Signed-off-by: Alex Deucher

drm: Don't free jobs in wait_event_interruptible()

2019-10-25T11:47:58Z

drm_sched_cleanup_jobs() attempts to free finished jobs, however because it is called as the condition of wait_event_interruptible() it must not sleep. Unfortunately some free callbacks (notably for Panfrost) do sleep. Instead let's rename drm_sched_cleanup_jobs() to drm_sched_get_cleanup_job() and simply return a job for processing if there is one. The caller can then call the free_job() callback outside the wait_event_interruptible() where sleeping is possible before re-checking and returning to sleep if necessary. Tested-by: Christian Gmeiner Fixes: 5918045c4ed4 ("drm/scheduler: rework job destruction") Signed-off-by: Steven Price Reviewed-by: Christian König Signed-off-by: Christian König Link: https://patchwork.freedesktop.org/patch/337652/

drm/scheduler: make unexported items static

2019-10-10T14:11:46Z

The drm_sched_fence_ops_{scheduled,finished} are not exported from the file so make them static to avoid the following warnings from sparse: drivers/gpu/drm/scheduler/sched_fence.c:131:28: warning: symbol 'drm_sched_fence_ops_scheduled' was not declared. Should it be static? drivers/gpu/drm/scheduler/sched_fence.c:137:28: warning: symbol 'drm_sched_fence_ops_finished' was not declared. Should it be static? Reviewed-by: Alex Deucher Signed-off-by: Ben Dooks Signed-off-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20191009121447.31017-1-ben.dooks@codethink.co.uk

drm/scheduler: use job count instead of peek

2019-08-15T15:52:10Z

The spsc_queue_peek function is accessing queue->head which belongs to the consumer thread and shouldn't be accessed by the producer This is fixing a rare race condition when destroying entities. Signed-off-by: Christian König Acked-by: Andrey Grodzovsky Reviewed-by: Monk.liu@amd.com Signed-off-by: Alex Deucher

drm/scheduler: drop use of drmP.h

2019-07-15T16:11:31Z

Drop use of the deprecated drmP.h header file. Fix fallout. Signed-off-by: Sam Ravnborg Reviewed-by: Christian König Acked-by: Emil Velikov Cc: David Airlie Cc: Daniel Vetter Cc: Alex Deucher Cc: Andrey Grodzovsky Cc: Huang Rui Cc: Eric Anholt Cc: Bas Nieuwenhuizen Cc: Sharat Masetty Cc: Nathan Chancellor Cc: Nayan Deshmukh Cc: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20190630061922.7254-26-sam@ravnborg.org