Messages in this thread | ![/](/images/icornerl.gif) | | Date | Sat, 4 May 2024 04:39:57 -0400 | From | Steven Rostedt <> | Subject | Re: [BUG][v6.9-rc6] Deadlock with: Revert "drm/qxl: simplify qxl_fence_wait" |
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Did anyone see this?
-- Steve
On Thu, 2 May 2024 08:16:41 -0400 Steven Rostedt <rostedt@goodmis.org> wrote:
> I went to run my tests on my VMs and the tests hung on boot up. > Unfortunately, the most I ever got out was: > > [ 93.607888] Testing event system initcall: OK > [ 93.667730] Running tests on all trace events: > [ 93.669757] Testing all events: OK > [ 95.631064] ------------[ cut here ]------------ > Timed out after 60 seconds > > I ran a bisect and it came up with: > > # first bad commit: [07ed11afb68d94eadd4ffc082b97c2331307c5ea] Revert "drm/qxl: simplify qxl_fence_wait" > > I checked out 07ed11afb68d94eadd4ffc082b97c2331307c5ea~1 and it booted > fine. Added back that commit, it failed to boot. I did this twice, and got > the same results. > > But the last time I ran it, it did trigger this: > > ------------[ cut here ]------------ > > ====================================================== > WARNING: possible circular locking dependency detected > 6.9.0-rc1-test-00021-g07ed11afb68d #5 Not tainted > ------------------------------------------------------ > kworker/u24:3/119 is trying to acquire lock: > ffffffff95aa4600 (console_owner){....}-{0:0}, at: console_flush_all+0x1f5/0x530 > > but task is already holding lock: > ffff93c4bbd37218 (&pool->lock){-.-.}-{2:2}, at: __flush_work+0xc1/0x440 > > which lock already depends on the new lock. > > > the existing dependency chain (in reverse order) is: > > -> #1 (&pool->lock){-.-.}-{2:2}: > _raw_spin_lock+0x33/0x40 > __queue_work+0xd6/0x610 > queue_work_on+0x8a/0x90 > soft_cursor+0x1a0/0x230 > bit_cursor+0x386/0x5f0 > hide_cursor+0x27/0xb0 > vt_console_print+0x474/0x490 > console_flush_all+0x22e/0x530 > console_unlock+0x56/0x160 > vprintk_emit+0x160/0x390 > dev_printk_emit+0xa5/0xd0 > _dev_info+0x79/0xa0 > __drm_fb_helper_initial_config_and_unlock+0x3a9/0x5f0 > drm_fbdev_generic_client_hotplug+0x69/0xc0 > drm_client_register+0x7b/0xc0 > qxl_pci_probe+0x107/0x1a0 > local_pci_probe+0x45/0xa0 > pci_device_probe+0xc7/0x240 > really_probe+0xd6/0x390 > __driver_probe_device+0x78/0x150 > driver_probe_device+0x1f/0x90 > __driver_attach+0xd6/0x1d0 > bus_for_each_dev+0x8f/0xe0 > bus_add_driver+0x119/0x220 > driver_register+0x59/0x100 > do_one_initcall+0x76/0x3c0 > kernel_init_freeable+0x3a5/0x5b0 > kernel_init+0x1a/0x1c0 > ret_from_fork+0x34/0x50 > ret_from_fork_asm+0x1a/0x30 > > -> #0 (console_owner){....}-{0:0}: > __lock_acquire+0x13e7/0x2180 > lock_acquire+0xd9/0x300 > console_flush_all+0x212/0x530 > console_unlock+0x56/0x160 > vprintk_emit+0x160/0x390 > _printk+0x64/0x80 > __warn_printk+0x8e/0x180 > check_flush_dependency+0xfd/0x120 > __flush_work+0xfa/0x440 > qxl_queue_garbage_collect+0x83/0x90 > qxl_fence_wait+0xa4/0x1a0 > dma_fence_wait_timeout+0x98/0x1e0 > dma_resv_wait_timeout+0x7f/0xe0 > ttm_bo_delayed_delete+0x2b/0x90 > process_one_work+0x228/0x740 > worker_thread+0x1dc/0x3c0 > kthread+0xf2/0x120 > ret_from_fork+0x34/0x50 > ret_from_fork_asm+0x1a/0x30 > > other info that might help us debug this: > > Possible unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(&pool->lock); > lock(console_owner); > lock(&pool->lock); > lock(console_owner); > > *** DEADLOCK *** > > 6 locks held by kworker/u24:3/119: > #0: ffff93c440245948 ((wq_completion)ttm){+.+.}-{0:0}, at: process_one_work+0x43a/0x740 > #1: ffffa01380d83e60 ((work_completion)(&bo->delayed_delete)){+.+.}-{0:0}, at: process_one_work+0x1e2/0x740 > #2: ffffffff95b17880 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x86/0x440 > #3: ffff93c4bbd37218 (&pool->lock){-.-.}-{2:2}, at: __flush_work+0xc1/0x440 > #4: ffffffff95b149c0 (console_lock){+.+.}-{0:0}, at: _printk+0x64/0x80 > #5: ffffffff95b14a10 (console_srcu){....}-{0:0}, at: console_flush_all+0x7b/0x530 > > stack backtrace: > CPU: 2 PID: 119 Comm: kworker/u24:3 Not tainted 6.9.0-rc1-test-00021-g07ed11afb68d #5 > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 > Workqueue: ttm ttm_bo_delayed_delete > Call Trace: > <TASK> > dump_stack_lvl+0x77/0xb0 > check_noncircular+0x148/0x160 > __lock_acquire+0x13e7/0x2180 > lock_acquire+0xd9/0x300 > ? console_flush_all+0x1f5/0x530 > ? lock_release+0x147/0x2c0 > ? console_flush_all+0x1f5/0x530 > console_flush_all+0x212/0x530 > ? console_flush_all+0x1f5/0x530 > console_unlock+0x56/0x160 > vprintk_emit+0x160/0x390 > _printk+0x64/0x80 > ? __pfx_ttm_bo_delayed_delete+0x10/0x10 > ? __pfx_qxl_gc_work+0x10/0x10 > __warn_printk+0x8e/0x180 > ? __pfx_ttm_bo_delayed_delete+0x10/0x10 > ? __pfx_qxl_gc_work+0x10/0x10 > ? __pfx_qxl_gc_work+0x10/0x10 > check_flush_dependency+0xfd/0x120 > __flush_work+0xfa/0x440 > qxl_queue_garbage_collect+0x83/0x90 > qxl_fence_wait+0xa4/0x1a0 > dma_fence_wait_timeout+0x98/0x1e0 > dma_resv_wait_timeout+0x7f/0xe0 > ttm_bo_delayed_delete+0x2b/0x90 > process_one_work+0x228/0x740 > worker_thread+0x1dc/0x3c0 > ? __pfx_worker_thread+0x10/0x10 > kthread+0xf2/0x120 > ? __pfx_kthread+0x10/0x10 > ret_from_fork+0x34/0x50 > ? __pfx_kthread+0x10/0x10 > ret_from_fork_asm+0x1a/0x30 > </TASK> > workqueue: WQ_MEM_RECLAIM ttm:ttm_bo_delayed_delete is flushing !WQ_MEM_RECLAIM events:qxl_gc_work > WARNING: CPU: 2 PID: 119 at kernel/workqueue.c:3728 check_flush_dependency+0xfd/0x120 > Modules linked in: > CPU: 2 PID: 119 Comm: kworker/u24:3 Not tainted 6.9.0-rc1-test-00021-g07ed11afb68d #5 > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 > Workqueue: ttm ttm_bo_delayed_delete > RIP: 0010:check_flush_dependency+0xfd/0x120 > Code: 8b 45 18 48 8d b2 70 01 00 00 49 89 e8 48 8d 8b 70 01 00 00 48 c7 c7 60 46 7b 95 c6 05 48 67 d2 01 01 48 89 c2 e8 63 40 fd ff <0f> 0b e9 1e ff ff ff 80 3d 33 67 d2 01 00 75 93 e9 4a ff ff ff 66 > RSP: 0000:ffffa01380d83c28 EFLAGS: 00010086 > RAX: 0000000000000000 RBX: ffff93c44004ee00 RCX: 0000000000000000 > RDX: 0000000080000003 RSI: 00000000ffffefff RDI: 0000000000000001 > RBP: ffffffff9497b100 R08: 0000000000000000 R09: 0000000000000003 > R10: ffffa01380d83ab8 R11: ffffffff95b14828 R12: ffff93c443980000 > R13: ffff93c440fbe300 R14: 0000000000000001 R15: ffff93c44004ee00 > FS: 0000000000000000(0000) GS:ffff93c4bbd00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000000 CR3: 000000007c864001 CR4: 0000000000170ef0 > Call Trace: > <TASK> > ? __warn+0x8c/0x180 > ? check_flush_dependency+0xfd/0x120 > ? report_bug+0x191/0x1c0 > ? prb_read_valid+0x1b/0x30 > ? handle_bug+0x3c/0x80 > ? exc_invalid_op+0x17/0x70 > ? asm_exc_invalid_op+0x1a/0x20 > ? __pfx_qxl_gc_work+0x10/0x10 > ? check_flush_dependency+0xfd/0x120 > ? check_flush_dependency+0xfd/0x120 > __flush_work+0xfa/0x440 > qxl_queue_garbage_collect+0x83/0x90 > qxl_fence_wait+0xa4/0x1a0 > dma_fence_wait_timeout+0x98/0x1e0 > dma_resv_wait_timeout+0x7f/0xe0 > ttm_bo_delayed_delete+0x2b/0x90 > process_one_work+0x228/0x740 > worker_thread+0x1dc/0x3c0 > ? __pfx_worker_thread+0x10/0x10 > kthread+0xf2/0x120 > ? __pfx_kthread+0x10/0x10 > ret_from_fork+0x34/0x50 > ? __pfx_kthread+0x10/0x10 > ret_from_fork_asm+0x1a/0x30 > </TASK> > irq event stamp: 58 > hardirqs last enabled at (57): [<ffffffff93fede30>] queue_work_on+0x60/0x90 > hardirqs last disabled at (58): [<ffffffff94ea7f66>] _raw_spin_lock_irq+0x56/0x60 > softirqs last enabled at (0): [<ffffffff93fbae27>] copy_process+0xc07/0x2c60 > softirqs last disabled at (0): [<0000000000000000>] 0x0 > ---[ end trace 0000000000000000 ]--- > > So there's an issue with dma_fence and a workqueue. > > -- Steve >
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