* v4.9-rc7 scrub kernel panic
@ 2016-12-13 3:15 Qu Wenruo
2016-12-20 7:30 ` Qu Wenruo
0 siblings, 1 reply; 4+ messages in thread
From: Qu Wenruo @ 2016-12-13 3:15 UTC (permalink / raw)
To: btrfs; +Cc: Chris Mason, David Sterba
Hi
When testing Chris' for-linus-4.10 branch.
I found that even at the branch base, v4.9-rc7, btrfs can't pass
quite a lot of scrub tests, including btrfs/011 and btrfs/069.
The btrfs/069 will fail 100%, with the following back trace:
general protection fault: 0000 [#1] SMP
Modules linked in: btrfs(O) xor zlib_deflate raid6_pq
x86_pkg_temp_thermal ext4 jbd2 mbcache e1000e efivarfs [last unloaded:
btrfs]
CPU: 3 PID: 5300 Comm: kworker/u8:4 Tainted: G O 4.9.0-rc7+ #20
Hardware name: FUJITSU ESPRIMO P720/D3221-A1, BIOS V4.6.5.4 R1.17.0 for
D3221-A1x 03/06/2014
Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs]
task: ffff88008dbcb740 task.stack: ffffc90001230000
RIP: 0010:[<ffffffff813a2fa8>] [<ffffffff813a2fa8>]
generic_make_request_checks+0x198/0x5a0
RSP: 0018:ffffc90001233b08 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff88007f963228 RCX: 0000000000000001
RDX: 0000000080000000 RSI: 0000000000000000 RDI: 6b6b6b6b6b6b6b6b
RBP: ffffc90001233b68 R08: 00000000868a9b14 R09: eab761b200000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000040
R13: 0000000000000004 R14: ffff88008dbc5a88 R15: 0000000000000010
FS: 0000000000000000(0000) GS:ffff880119e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000019c7058 CR3: 00000001150b4000 CR4: 00000000001406e0
Stack:
0000000000000002 ffffffff813a4cff ffffffff00000000 0000000000000296
0000000000000292 ffff88008dbcb740 ffffffff00000003 ffff88007f963228
00000000ffffffff 0000000000000004 ffff88008dbc5a88 0000000000000010
Call Trace:
[<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
[<ffffffff813a4c54>] generic_make_request+0x24/0x290
[<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
[<ffffffff813a4f2e>] submit_bio+0x6e/0x120
[<ffffffffa087279d>] ? page_in_rbio+0x4d/0x80 [btrfs]
[<ffffffffa08737d0>] ? rbio_orig_end_io+0x80/0x80 [btrfs]
[<ffffffffa0873e31>] finish_rmw+0x401/0x550 [btrfs]
[<ffffffffa0874fc6>] validate_rbio_for_rmw+0x36/0x40 [btrfs]
[<ffffffffa087504d>] raid_rmw_end_io+0x7d/0x90 [btrfs]
[<ffffffff8139c536>] bio_endio+0x56/0x60
[<ffffffffa07e6e5c>] end_workqueue_fn+0x3c/0x40 [btrfs]
[<ffffffffa08285bf>] btrfs_scrubparity_helper+0xef/0x610 [btrfs]
[<ffffffffa0828b9e>] btrfs_endio_raid56_helper+0xe/0x10 [btrfs]
[<ffffffff810ec8df>] process_one_work+0x2af/0x720
[<ffffffff810ec85b>] ? process_one_work+0x22b/0x720
[<ffffffff810ecd9b>] worker_thread+0x4b/0x4f0
[<ffffffff810ecd50>] ? process_one_work+0x720/0x720
[<ffffffff810ecd50>] ? process_one_work+0x720/0x720
[<ffffffff810f39d3>] kthread+0xf3/0x110
[<ffffffff810f38e0>] ? kthread_park+0x60/0x60
[<ffffffff81857647>] ret_from_fork+0x27/0x40
Code: 00 00 0f 1f 44 00 00 65 8b 05 9d 71 c6 7e 89 c0 48 0f a3 05 c3 13
b8 00 0f 92 c3 0f 82 dd 02 00 00 bb 01 00 00 00 e9 8c 00 00 00 <48> 8b
47 08 48 8b 40 50 48 c1 f8 09 48 85 c0 0f 84 99 fe ff ff
RIP [<ffffffff813a2fa8>] generic_make_request_checks+0x198/0x5a0
RSP <ffffc90001233b08>
Is this a known bug or a new one caused by the block layer change?
Thanks,
Qu
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: v4.9-rc7 scrub kernel panic
2016-12-13 3:15 v4.9-rc7 scrub kernel panic Qu Wenruo
@ 2016-12-20 7:30 ` Qu Wenruo
2017-01-05 6:02 ` Qu Wenruo
2017-01-11 6:13 ` Qu Wenruo
0 siblings, 2 replies; 4+ messages in thread
From: Qu Wenruo @ 2016-12-20 7:30 UTC (permalink / raw)
To: btrfs; +Cc: Chris Mason, David Sterba
Further info:
I tested several versions of old kernel starts from v4.7, and they all
failed on two of my physical machines.
But strangely, they all passed in KVM guests using virtio.
Not sure if it's related to the device size (over 50G for each device in
physical machines, while less than 10G for each in VM)
And the profile causing the problem is, unsurprisingly, RAID5 and RAID6.
For other profile it seems to be OK.
Thanks,
Qu
At 12/13/2016 11:15 AM, Qu Wenruo wrote:
> Hi
>
> When testing Chris' for-linus-4.10 branch.
>
> I found that even at the branch base, v4.9-rc7, btrfs can't pass
> quite a lot of scrub tests, including btrfs/011 and btrfs/069.
>
> The btrfs/069 will fail 100%, with the following back trace:
>
> general protection fault: 0000 [#1] SMP
> Modules linked in: btrfs(O) xor zlib_deflate raid6_pq
> x86_pkg_temp_thermal ext4 jbd2 mbcache e1000e efivarfs [last unloaded:
> btrfs]
> CPU: 3 PID: 5300 Comm: kworker/u8:4 Tainted: G O 4.9.0-rc7+
> #20
> Hardware name: FUJITSU ESPRIMO P720/D3221-A1, BIOS V4.6.5.4 R1.17.0 for
> D3221-A1x 03/06/2014
> Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs]
> task: ffff88008dbcb740 task.stack: ffffc90001230000
> RIP: 0010:[<ffffffff813a2fa8>] [<ffffffff813a2fa8>]
> generic_make_request_checks+0x198/0x5a0
> RSP: 0018:ffffc90001233b08 EFLAGS: 00010202
> RAX: 0000000000000000 RBX: ffff88007f963228 RCX: 0000000000000001
> RDX: 0000000080000000 RSI: 0000000000000000 RDI: 6b6b6b6b6b6b6b6b
> RBP: ffffc90001233b68 R08: 00000000868a9b14 R09: eab761b200000000
> R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000040
> R13: 0000000000000004 R14: ffff88008dbc5a88 R15: 0000000000000010
> FS: 0000000000000000(0000) GS:ffff880119e00000(0000)
> knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000019c7058 CR3: 00000001150b4000 CR4: 00000000001406e0
> Stack:
> 0000000000000002 ffffffff813a4cff ffffffff00000000 0000000000000296
> 0000000000000292 ffff88008dbcb740 ffffffff00000003 ffff88007f963228
> 00000000ffffffff 0000000000000004 ffff88008dbc5a88 0000000000000010
> Call Trace:
> [<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
> [<ffffffff813a4c54>] generic_make_request+0x24/0x290
> [<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
> [<ffffffff813a4f2e>] submit_bio+0x6e/0x120
> [<ffffffffa087279d>] ? page_in_rbio+0x4d/0x80 [btrfs]
> [<ffffffffa08737d0>] ? rbio_orig_end_io+0x80/0x80 [btrfs]
> [<ffffffffa0873e31>] finish_rmw+0x401/0x550 [btrfs]
> [<ffffffffa0874fc6>] validate_rbio_for_rmw+0x36/0x40 [btrfs]
> [<ffffffffa087504d>] raid_rmw_end_io+0x7d/0x90 [btrfs]
> [<ffffffff8139c536>] bio_endio+0x56/0x60
> [<ffffffffa07e6e5c>] end_workqueue_fn+0x3c/0x40 [btrfs]
> [<ffffffffa08285bf>] btrfs_scrubparity_helper+0xef/0x610 [btrfs]
> [<ffffffffa0828b9e>] btrfs_endio_raid56_helper+0xe/0x10 [btrfs]
> [<ffffffff810ec8df>] process_one_work+0x2af/0x720
> [<ffffffff810ec85b>] ? process_one_work+0x22b/0x720
> [<ffffffff810ecd9b>] worker_thread+0x4b/0x4f0
> [<ffffffff810ecd50>] ? process_one_work+0x720/0x720
> [<ffffffff810ecd50>] ? process_one_work+0x720/0x720
> [<ffffffff810f39d3>] kthread+0xf3/0x110
> [<ffffffff810f38e0>] ? kthread_park+0x60/0x60
> [<ffffffff81857647>] ret_from_fork+0x27/0x40
> Code: 00 00 0f 1f 44 00 00 65 8b 05 9d 71 c6 7e 89 c0 48 0f a3 05 c3 13
> b8 00 0f 92 c3 0f 82 dd 02 00 00 bb 01 00 00 00 e9 8c 00 00 00 <48> 8b
> 47 08 48 8b 40 50 48 c1 f8 09 48 85 c0 0f 84 99 fe ff ff
> RIP [<ffffffff813a2fa8>] generic_make_request_checks+0x198/0x5a0
> RSP <ffffc90001233b08>
>
> Is this a known bug or a new one caused by the block layer change?
>
> Thanks,
> Qu
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: v4.9-rc7 scrub kernel panic
2016-12-20 7:30 ` Qu Wenruo
@ 2017-01-05 6:02 ` Qu Wenruo
2017-01-11 6:13 ` Qu Wenruo
1 sibling, 0 replies; 4+ messages in thread
From: Qu Wenruo @ 2017-01-05 6:02 UTC (permalink / raw)
To: Qu Wenruo, btrfs; +Cc: Chris Mason, David Sterba
Sometimes I got kernel NULL pointer warning like:
[ 778.248521] BUG: unable to handle kernel NULL pointer dereference at
00000000000005f0
[ 778.249728] IP: generic_make_request_checks+0x4d/0x610
And the address 0x5f0 is just ((struct block_device *)0)->bd_disk->queue.
I added some extra WARN_ON/BUG_ON() to rbio_add_io_page() where we set
io->bi_dev.
And unsurprisingly, that WAR_ON/BUG_ON() got triggered even we checked
stripe->dev->bdev before allocating new bio.
So there must be some race which corrupts stripe->dev->bdev.
I'll keep digging but if any one can reproduce the bug, it would be
quite helpful to reproduce the bug by running fstests/btrfs/069.
Thanks,
Qu
At 12/20/2016 03:30 PM, Qu Wenruo wrote:
> Further info:
>
> I tested several versions of old kernel starts from v4.7, and they all
> failed on two of my physical machines.
>
> But strangely, they all passed in KVM guests using virtio.
>
> Not sure if it's related to the device size (over 50G for each device in
> physical machines, while less than 10G for each in VM)
>
> And the profile causing the problem is, unsurprisingly, RAID5 and RAID6.
>
> For other profile it seems to be OK.
>
> Thanks,
> Qu
>
> At 12/13/2016 11:15 AM, Qu Wenruo wrote:
>> Hi
>>
>> When testing Chris' for-linus-4.10 branch.
>>
>> I found that even at the branch base, v4.9-rc7, btrfs can't pass
>> quite a lot of scrub tests, including btrfs/011 and btrfs/069.
>>
>> The btrfs/069 will fail 100%, with the following back trace:
>>
>> general protection fault: 0000 [#1] SMP
>> Modules linked in: btrfs(O) xor zlib_deflate raid6_pq
>> x86_pkg_temp_thermal ext4 jbd2 mbcache e1000e efivarfs [last unloaded:
>> btrfs]
>> CPU: 3 PID: 5300 Comm: kworker/u8:4 Tainted: G O 4.9.0-rc7+
>> #20
>> Hardware name: FUJITSU ESPRIMO P720/D3221-A1, BIOS V4.6.5.4 R1.17.0 for
>> D3221-A1x 03/06/2014
>> Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs]
>> task: ffff88008dbcb740 task.stack: ffffc90001230000
>> RIP: 0010:[<ffffffff813a2fa8>] [<ffffffff813a2fa8>]
>> generic_make_request_checks+0x198/0x5a0
>> RSP: 0018:ffffc90001233b08 EFLAGS: 00010202
>> RAX: 0000000000000000 RBX: ffff88007f963228 RCX: 0000000000000001
>> RDX: 0000000080000000 RSI: 0000000000000000 RDI: 6b6b6b6b6b6b6b6b
>> RBP: ffffc90001233b68 R08: 00000000868a9b14 R09: eab761b200000000
>> R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000040
>> R13: 0000000000000004 R14: ffff88008dbc5a88 R15: 0000000000000010
>> FS: 0000000000000000(0000) GS:ffff880119e00000(0000)
>> knlGS:0000000000000000
>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00000000019c7058 CR3: 00000001150b4000 CR4: 00000000001406e0
>> Stack:
>> 0000000000000002 ffffffff813a4cff ffffffff00000000 0000000000000296
>> 0000000000000292 ffff88008dbcb740 ffffffff00000003 ffff88007f963228
>> 00000000ffffffff 0000000000000004 ffff88008dbc5a88 0000000000000010
>> Call Trace:
>> [<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
>> [<ffffffff813a4c54>] generic_make_request+0x24/0x290
>> [<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
>> [<ffffffff813a4f2e>] submit_bio+0x6e/0x120
>> [<ffffffffa087279d>] ? page_in_rbio+0x4d/0x80 [btrfs]
>> [<ffffffffa08737d0>] ? rbio_orig_end_io+0x80/0x80 [btrfs]
>> [<ffffffffa0873e31>] finish_rmw+0x401/0x550 [btrfs]
>> [<ffffffffa0874fc6>] validate_rbio_for_rmw+0x36/0x40 [btrfs]
>> [<ffffffffa087504d>] raid_rmw_end_io+0x7d/0x90 [btrfs]
>> [<ffffffff8139c536>] bio_endio+0x56/0x60
>> [<ffffffffa07e6e5c>] end_workqueue_fn+0x3c/0x40 [btrfs]
>> [<ffffffffa08285bf>] btrfs_scrubparity_helper+0xef/0x610 [btrfs]
>> [<ffffffffa0828b9e>] btrfs_endio_raid56_helper+0xe/0x10 [btrfs]
>> [<ffffffff810ec8df>] process_one_work+0x2af/0x720
>> [<ffffffff810ec85b>] ? process_one_work+0x22b/0x720
>> [<ffffffff810ecd9b>] worker_thread+0x4b/0x4f0
>> [<ffffffff810ecd50>] ? process_one_work+0x720/0x720
>> [<ffffffff810ecd50>] ? process_one_work+0x720/0x720
>> [<ffffffff810f39d3>] kthread+0xf3/0x110
>> [<ffffffff810f38e0>] ? kthread_park+0x60/0x60
>> [<ffffffff81857647>] ret_from_fork+0x27/0x40
>> Code: 00 00 0f 1f 44 00 00 65 8b 05 9d 71 c6 7e 89 c0 48 0f a3 05 c3 13
>> b8 00 0f 92 c3 0f 82 dd 02 00 00 bb 01 00 00 00 e9 8c 00 00 00 <48> 8b
>> 47 08 48 8b 40 50 48 c1 f8 09 48 85 c0 0f 84 99 fe ff ff
>> RIP [<ffffffff813a2fa8>] generic_make_request_checks+0x198/0x5a0
>> RSP <ffffc90001233b08>
>>
>> Is this a known bug or a new one caused by the block layer change?
>>
>> Thanks,
>> Qu
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: v4.9-rc7 scrub kernel panic
2016-12-20 7:30 ` Qu Wenruo
2017-01-05 6:02 ` Qu Wenruo
@ 2017-01-11 6:13 ` Qu Wenruo
1 sibling, 0 replies; 4+ messages in thread
From: Qu Wenruo @ 2017-01-11 6:13 UTC (permalink / raw)
To: btrfs; +Cc: Chris Mason, David Sterba
Located the problem:
It's dev-replace which frees devices without protection on cancel:
Process A (dev-replace) | Process B(scrub)
----------------------------------------------------------------------
|(Any RW is OK)
|scrub_setup_recheck_block()
||- btrfs_map_sblock()
| Got a bbio with tgtdev
btrfs_dev_replace_finishing() |
|- btrfs_destory_dev_replace_tgtdev()|
|- call_rcu(free_device) |
|- __free_device() |
|- kfree(device) |
| Scrub worker:
| Access bbio->stripes[], which
| contains tgtdev.
| This triggers general protection.
Currently btrfs/069 is the best method to trigger it, since scrub will
interrupt dev-replace and cause enough IO to trigger the bug.
I'm trying to fix it by introducing a new atomic refs and
wait_queue_head for btrfs_device, and each btrfs_map_block will increase
the refs, free_bbio() will decrease it when before freeing the bbio.
Any idea on existing facilities to wait btrfs_device before destroying
it is welcomed to fix this problem.
Thanks,
Qu
At 12/20/2016 03:30 PM, Qu Wenruo wrote:
> Further info:
>
> I tested several versions of old kernel starts from v4.7, and they all
> failed on two of my physical machines.
>
> But strangely, they all passed in KVM guests using virtio.
>
> Not sure if it's related to the device size (over 50G for each device in
> physical machines, while less than 10G for each in VM)
>
> And the profile causing the problem is, unsurprisingly, RAID5 and RAID6.
>
> For other profile it seems to be OK.
>
> Thanks,
> Qu
>
> At 12/13/2016 11:15 AM, Qu Wenruo wrote:
>> Hi
>>
>> When testing Chris' for-linus-4.10 branch.
>>
>> I found that even at the branch base, v4.9-rc7, btrfs can't pass
>> quite a lot of scrub tests, including btrfs/011 and btrfs/069.
>>
>> The btrfs/069 will fail 100%, with the following back trace:
>>
>> general protection fault: 0000 [#1] SMP
>> Modules linked in: btrfs(O) xor zlib_deflate raid6_pq
>> x86_pkg_temp_thermal ext4 jbd2 mbcache e1000e efivarfs [last unloaded:
>> btrfs]
>> CPU: 3 PID: 5300 Comm: kworker/u8:4 Tainted: G O 4.9.0-rc7+
>> #20
>> Hardware name: FUJITSU ESPRIMO P720/D3221-A1, BIOS V4.6.5.4 R1.17.0 for
>> D3221-A1x 03/06/2014
>> Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs]
>> task: ffff88008dbcb740 task.stack: ffffc90001230000
>> RIP: 0010:[<ffffffff813a2fa8>] [<ffffffff813a2fa8>]
>> generic_make_request_checks+0x198/0x5a0
>> RSP: 0018:ffffc90001233b08 EFLAGS: 00010202
>> RAX: 0000000000000000 RBX: ffff88007f963228 RCX: 0000000000000001
>> RDX: 0000000080000000 RSI: 0000000000000000 RDI: 6b6b6b6b6b6b6b6b
>> RBP: ffffc90001233b68 R08: 00000000868a9b14 R09: eab761b200000000
>> R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000040
>> R13: 0000000000000004 R14: ffff88008dbc5a88 R15: 0000000000000010
>> FS: 0000000000000000(0000) GS:ffff880119e00000(0000)
>> knlGS:0000000000000000
>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00000000019c7058 CR3: 00000001150b4000 CR4: 00000000001406e0
>> Stack:
>> 0000000000000002 ffffffff813a4cff ffffffff00000000 0000000000000296
>> 0000000000000292 ffff88008dbcb740 ffffffff00000003 ffff88007f963228
>> 00000000ffffffff 0000000000000004 ffff88008dbc5a88 0000000000000010
>> Call Trace:
>> [<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
>> [<ffffffff813a4c54>] generic_make_request+0x24/0x290
>> [<ffffffff813a4cff>] ? generic_make_request+0xcf/0x290
>> [<ffffffff813a4f2e>] submit_bio+0x6e/0x120
>> [<ffffffffa087279d>] ? page_in_rbio+0x4d/0x80 [btrfs]
>> [<ffffffffa08737d0>] ? rbio_orig_end_io+0x80/0x80 [btrfs]
>> [<ffffffffa0873e31>] finish_rmw+0x401/0x550 [btrfs]
>> [<ffffffffa0874fc6>] validate_rbio_for_rmw+0x36/0x40 [btrfs]
>> [<ffffffffa087504d>] raid_rmw_end_io+0x7d/0x90 [btrfs]
>> [<ffffffff8139c536>] bio_endio+0x56/0x60
>> [<ffffffffa07e6e5c>] end_workqueue_fn+0x3c/0x40 [btrfs]
>> [<ffffffffa08285bf>] btrfs_scrubparity_helper+0xef/0x610 [btrfs]
>> [<ffffffffa0828b9e>] btrfs_endio_raid56_helper+0xe/0x10 [btrfs]
>> [<ffffffff810ec8df>] process_one_work+0x2af/0x720
>> [<ffffffff810ec85b>] ? process_one_work+0x22b/0x720
>> [<ffffffff810ecd9b>] worker_thread+0x4b/0x4f0
>> [<ffffffff810ecd50>] ? process_one_work+0x720/0x720
>> [<ffffffff810ecd50>] ? process_one_work+0x720/0x720
>> [<ffffffff810f39d3>] kthread+0xf3/0x110
>> [<ffffffff810f38e0>] ? kthread_park+0x60/0x60
>> [<ffffffff81857647>] ret_from_fork+0x27/0x40
>> Code: 00 00 0f 1f 44 00 00 65 8b 05 9d 71 c6 7e 89 c0 48 0f a3 05 c3 13
>> b8 00 0f 92 c3 0f 82 dd 02 00 00 bb 01 00 00 00 e9 8c 00 00 00 <48> 8b
>> 47 08 48 8b 40 50 48 c1 f8 09 48 85 c0 0f 84 99 fe ff ff
>> RIP [<ffffffff813a2fa8>] generic_make_request_checks+0x198/0x5a0
>> RSP <ffffc90001233b08>
>>
>> Is this a known bug or a new one caused by the block layer change?
>>
>> Thanks,
>> Qu
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2017-01-11 6:13 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2016-12-13 3:15 v4.9-rc7 scrub kernel panic Qu Wenruo
2016-12-20 7:30 ` Qu Wenruo
2017-01-05 6:02 ` Qu Wenruo
2017-01-11 6:13 ` Qu Wenruo
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