Yeah I was also looking into this problem Our sched_main routine need to access entity after "sched_select_entity", but after selected the entity may just get released by context free So the following entity accessing may operate on wild pointer, Although I have a patch to fix it, but I don't know how to deal with the same wild pointer issue in "sched_job_recovery", for my gpu reset feature BR Monk -----Original Message----- From: amd-gfx [mailto:amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx] On Behalf Of Chunming Zhou Sent: 2017å¹´10æ??24æ?¥ 17:56 To: amd-gfx at lists.freedesktop.org Cc: Zhou, David(ChunMing) <David1.Zhou at amd.com> Subject: [PATCH] drm/amd/scheduler: fix one used-after-free case for job->s_entity The s_entity presented process could already be closed when calling amdgpu_job_free_cb. the s_entity will be buggy pointer after it's freed. See below calltrace: [ 355.616964] ================================================================== [ 355.617191] BUG: KASAN: use-after-free in amdgpu_job_free_cb+0x2f/0xc0 [amdgpu] [ 355.617197] Read of size 8 at addr ffff88039d593c40 by task kworker/9:1/100 [ 355.617206] CPU: 9 PID: 100 Comm: kworker/9:1 Not tainted 4.13.0-custom #1 [ 355.617208] Hardware name: Gigabyte Technology Co., Ltd. Default string/X99P-SLI-CF, BIOS F23 07/22/2016 [ 355.617342] Workqueue: events amd_sched_job_finish [amdgpu] [ 355.617344] Call Trace: [ 355.617351] dump_stack+0x63/0x8d [ 355.617356] print_address_description+0x70/0x290 [ 355.617474] ? amdgpu_job_free_cb+0x2f/0xc0 [amdgpu] [ 355.617477] kasan_report+0x265/0x350 [ 355.617479] __asan_load8+0x54/0x90 [ 355.617603] amdgpu_job_free_cb+0x2f/0xc0 [amdgpu] [ 355.617721] amd_sched_job_finish+0x161/0x180 [amdgpu] [ 355.617725] process_one_work+0x2ab/0x700 [ 355.617727] worker_thread+0x90/0x720 [ 355.617731] kthread+0x18c/0x1e0 [ 355.617732] ? process_one_work+0x700/0x700 [ 355.617735] ? kthread_create_on_node+0xb0/0xb0 [ 355.617738] ret_from_fork+0x25/0x30 [ 355.617742] Allocated by task 1347: [ 355.617747] save_stack_trace+0x1b/0x20 [ 355.617749] save_stack+0x46/0xd0 [ 355.617751] kasan_kmalloc+0xad/0xe0 [ 355.617753] kmem_cache_alloc_trace+0xef/0x200 [ 355.617853] amdgpu_driver_open_kms+0x98/0x290 [amdgpu] [ 355.617883] drm_open+0x38c/0x6e0 [drm] [ 355.617908] drm_stub_open+0x144/0x1b0 [drm] [ 355.617911] chrdev_open+0x180/0x320 [ 355.617913] do_dentry_open+0x3a2/0x570 [ 355.617915] vfs_open+0x86/0xe0 [ 355.617918] path_openat+0x49e/0x1db0 [ 355.617919] do_filp_open+0x11c/0x1a0 [ 355.617921] do_sys_open+0x16f/0x2a0 [ 355.617923] SyS_open+0x1e/0x20 [ 355.617926] do_syscall_64+0xea/0x210 [ 355.617928] return_from_SYSCALL_64+0x0/0x6a [ 355.617931] Freed by task 1347: [ 355.617934] save_stack_trace+0x1b/0x20 [ 355.617936] save_stack+0x46/0xd0 [ 355.617937] kasan_slab_free+0x70/0xc0 [ 355.617939] kfree+0x9d/0x1c0 [ 355.618038] amdgpu_driver_postclose_kms+0x1bc/0x3e0 [amdgpu] [ 355.618063] drm_release+0x454/0x610 [drm] [ 355.618065] __fput+0x177/0x350 [ 355.618066] ____fput+0xe/0x10 [ 355.618068] task_work_run+0xa0/0xc0 [ 355.618070] do_exit+0x456/0x1320 [ 355.618072] do_group_exit+0x86/0x130 [ 355.618074] SyS_exit_group+0x1d/0x20 [ 355.618076] do_syscall_64+0xea/0x210 [ 355.618078] return_from_SYSCALL_64+0x0/0x6a [ 355.618081] The buggy address belongs to the object at ffff88039d593b80 which belongs to the cache kmalloc-2048 of size 2048 [ 355.618085] The buggy address is located 192 bytes inside of 2048-byte region [ffff88039d593b80, ffff88039d594380) [ 355.618087] The buggy address belongs to the page: [ 355.618091] page:ffffea000e756400 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 355.618095] flags: 0x2ffff0000008100(slab|head) [ 355.618099] raw: 02ffff0000008100 0000000000000000 0000000000000000 00000001000f000f [ 355.618103] raw: ffffea000edb0600 0000000200000002 ffff8803bfc0ea00 0000000000000000 [ 355.618105] page dumped because: kasan: bad access detected [ 355.618108] Memory state around the buggy address: [ 355.618110] ffff88039d593b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 355.618113] ffff88039d593b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 355.618116] >ffff88039d593c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 355.618117] ^ [ 355.618120] ffff88039d593c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 355.618122] ffff88039d593d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 355.618124] ================================================================== [ 355.618126] Disabling lock debugging due to kernel taint Change-Id: I8ff7122796b8cd16fc26e9c40e8d4c8153d67e0c Signed-off-by: Chunming Zhou <david1.zhou at amd.com> --- drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 1 + drivers/gpu/drm/amd/scheduler/gpu_scheduler.h | 27 ++++++++++++++------------- 2 files changed, 15 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c index 007fdbd..8101ed7 100644 --- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c @@ -535,6 +535,7 @@ int amd_sched_job_init(struct amd_sched_job *job, if (!job->s_fence) return -ENOMEM; job->id = atomic64_inc_return(&sched->job_id_count); + job->priority = job->s_entity->rq - job->sched->sched_rq; INIT_WORK(&job->finish_work, amd_sched_job_finish); INIT_LIST_HEAD(&job->node); diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h index e21299c..8808eb1 100644 --- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h @@ -77,6 +77,18 @@ struct amd_sched_fence { void *owner; }; +enum amd_sched_priority { + AMD_SCHED_PRIORITY_MIN, + AMD_SCHED_PRIORITY_LOW = AMD_SCHED_PRIORITY_MIN, + AMD_SCHED_PRIORITY_NORMAL, + AMD_SCHED_PRIORITY_HIGH_SW, + AMD_SCHED_PRIORITY_HIGH_HW, + AMD_SCHED_PRIORITY_KERNEL, + AMD_SCHED_PRIORITY_MAX, + AMD_SCHED_PRIORITY_INVALID = -1, + AMD_SCHED_PRIORITY_UNSET = -2 +}; + struct amd_sched_job { struct amd_gpu_scheduler *sched; struct amd_sched_entity *s_entity; @@ -87,6 +99,7 @@ struct amd_sched_job { struct delayed_work work_tdr; uint64_t id; atomic_t karma; + enum amd_sched_priority priority; }; extern const struct dma_fence_ops amd_sched_fence_ops_scheduled; @@ -118,18 +131,6 @@ struct amd_sched_backend_ops { void (*free_job)(struct amd_sched_job *sched_job); }; -enum amd_sched_priority { - AMD_SCHED_PRIORITY_MIN, - AMD_SCHED_PRIORITY_LOW = AMD_SCHED_PRIORITY_MIN, - AMD_SCHED_PRIORITY_NORMAL, - AMD_SCHED_PRIORITY_HIGH_SW, - AMD_SCHED_PRIORITY_HIGH_HW, - AMD_SCHED_PRIORITY_KERNEL, - AMD_SCHED_PRIORITY_MAX, - AMD_SCHED_PRIORITY_INVALID = -1, - AMD_SCHED_PRIORITY_UNSET = -2 -}; - /** * One scheduler is implemented for each hardware ring */ @@ -183,7 +184,7 @@ void amd_sched_job_kickout(struct amd_sched_job *s_job); static inline enum amd_sched_priority amd_sched_get_job_priority(struct amd_sched_job *job) { - return (job->s_entity->rq - job->sched->sched_rq); + return job->priority; } #endif -- 2.7.4 _______________________________________________ amd-gfx mailing list amd-gfx at lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx
