radeon: 4.2-rc1 warning when unplugging DVI

[Alex Deucher]

On Mon, Jul 6, 2015 at 3:19 PM, Dave Jones <davej at codemonkey.org.uk> wrote:
> I wanted to switch my LCD to a different machine momentarily.
> When I plugged the cable back in, this was on the screen..

Is this readily reproducible?  Did it happen with 4.1?  If it also
happens with 4.1 does reverting
39fa10f7e21574a70cecf1fed0f9b36535aa68a0 help?  If it doesn't happen
with 4.1, can you bisect?

Alex

>
> WARNING: CPU: 1 PID: 209 at kernel/locking/mutex.c:526 __mutex_lock_slowpath+0x322/0x340()
> DEBUG_LOCKS_WARN_ON(l->magic != l)
> CPU: 1 PID: 209 Comm: kworker/1:3 Not tainted 4.2.0-rc1-gelk-debug+ #1
> Workqueue: events radeon_hotplug_work_func [radeon]
>  0000000000000009 ffff8800b160bc78 ffffffff9969fad4 0000000080000001
>  ffff8800b160bcc8 ffff8800b160bcb8 ffffffff9907689a 00000000000086be
>  ffff8800a24182b8 ffff8800a24182c0 ffff8800b086adc0 ffff8800a24182b8
> Call Trace:
>  [<ffffffff9969fad4>] dump_stack+0x4f/0x7b
>  [<ffffffff9907689a>] warn_slowpath_common+0x8a/0xc0
>  [<ffffffff99076916>] warn_slowpath_fmt+0x46/0x50
>  [<ffffffff996a54f2>] __mutex_lock_slowpath+0x322/0x340
>  [<ffffffff996a553c>] mutex_lock+0x2c/0x40
>  [<ffffffffc02895e6>] radeon_hotplug_work_func+0x26/0x80 [radeon]
>  [<ffffffff9908eba7>] process_one_work+0x147/0x420
>  [<ffffffff9908f209>] worker_thread+0x69/0x470
>  [<ffffffff990a02b3>] ? preempt_count_sub+0xa3/0xf0
>  [<ffffffff9908f1a0>] ? rescuer_thread+0x320/0x320
>  [<ffffffff990941e7>] kthread+0x107/0x120
>  [<ffffffff990940e0>] ? kthread_create_on_node+0x1b0/0x1b0
>  [<ffffffff996a7b1f>] ret_from_fork+0x3f/0x70
>  [<ffffffff990940e0>] ? kthread_create_on_node+0x1b0/0x1b0
> ---[ end trace 859b3faf9cb20dd3 ]---
> Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
> CPU: 1 PID: 209 Comm: kworker/1:3 Tainted: G        W       4.2.0-rc1-gelk-debug+ #1
> Workqueue: events radeon_hotplug_work_func [radeon]
> task: ffff8800b086adc0 ti: ffff8800b1608000 task.ti: ffff8800b1608000
> RIP: 0010:[<ffffffff9932ffef>]  [<ffffffff9932ffef>] __list_add+0x1f/0xc0
> RSP: 0018:ffff8800b160bcf8  EFLAGS: 00010046
> RAX: ffff8800a24182d8 RBX: ffff8800b160bd38 RCX: 0000000000000000
> RDX: ffff8800a24182d8 RSI: 0000000000000000 RDI: ffff8800b160bd38
> RBP: ffff8800b160bd18 R08: 0000000000000000 R09: 0000000000000fcb
> R10: 0000000000000353 R11: 00000000ffffffff R12: ffff8800a24182d8
> R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000246
> FS:  0000000000000000(0000) GS:ffff8800bf700000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> CR2: 0000000000000000 CR3: 00000000a25d3000 CR4: 00000000000007e0
> Stack:
>  ffff8800b160bd18 ffff8800a24182b8 ffff8800a24182c0 ffff8800b086adc0
>  ffff8800b160bd88 ffffffff996a5291 ffff8800b160bd58 ffff8800a24182d8
>  ffff8800b160bd38 ffff8800b160bd38 1111111111111111 ffff8800b160bd38
> Call Trace:
>  [<ffffffff996a5291>] __mutex_lock_slowpath+0xc1/0x340
>  [<ffffffff996a553c>] mutex_lock+0x2c/0x40
>  [<ffffffffc02895e6>] radeon_hotplug_work_func+0x26/0x80 [radeon]
>  [<ffffffff9908eba7>] process_one_work+0x147/0x420
>  [<ffffffff9908f209>] worker_thread+0x69/0x470
>  [<ffffffff990a02b3>] ? preempt_count_sub+0xa3/0xf0
>  [<ffffffff9908f1a0>] ? rescuer_thread+0x320/0x320
>  [<ffffffff990941e7>] kthread+0x107/0x120
>  [<ffffffff990940e0>] ? kthread_create_on_node+0x1b0/0x1b0
>  [<ffffffff996a7b1f>] ret_from_fork+0x3f/0x70
>  [<ffffffff990940e0>] ? kthread_create_on_node+0x1b0/0x1b0
> Code: c3 66 2e 0f 1f 84 00 00 00 00 00 90 55 48 89 e5 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb 48 83 ec 08 4c 8b 42 08 49 39 f0 75 2e <4d> 8b 45 00 4d 39 c4 75 4e 4c 39 e3 74 6b 4c 39 eb 74 66 49 89
>
>
> radeon is an RV370.
>
>         Dave