From: Chris Mason <clm@fb.com>
To: Martin Steigerwald <Martin@lichtvoll.de>
Cc: Liu Bo <bo.li.liu@oracle.com>, <linux-btrfs@vger.kernel.org>
Subject: Re: [PATCH] Btrfs: fix compressed write corruption on enospc
Date: Wed, 6 Aug 2014 11:18:16 -0400 [thread overview]
Message-ID: <53E24738.5070908@fb.com> (raw)
In-Reply-To: <4178355.kT8uO1WxjX@merkaba>
On 08/06/2014 10:43 AM, Martin Steigerwald wrote:
> Am Mittwoch, 6. August 2014, 09:35:51 schrieb Chris Mason:
>> On 08/06/2014 06:21 AM, Martin Steigerwald wrote:
>>>> I think this should go to stable. Thanks, Liu.
>>
>> I'm definitely tagging this for stable.
>>
>>> Unfortunately this fix does not seem to fix all lockups.
>>
>> The traces below are a little different, could you please send the whole
>> file?
>
> Will paste it at the end.
[90496.156016] kworker/u8:14 D ffff880044e38540 0 21050 2 0x00000000
[90496.157683] Workqueue: btrfs-delalloc normal_work_helper [btrfs]
[90496.159320] ffff88022880f990 0000000000000002 ffff880407f649b0 ffff88022880ffd8
[90496.160997] ffff880044e38000 0000000000013040 ffff880044e38000 7fffffffffffffff
[90496.162686] ffff880301383aa0 0000000000000002 ffffffff814705d0 ffff880301383a98
[90496.164360] Call Trace:
[90496.166028] [<ffffffff814705d0>] ? michael_mic.part.6+0x21/0x21
[90496.167854] [<ffffffff81470fd0>] schedule+0x64/0x66
[90496.169574] [<ffffffff814705ff>] schedule_timeout+0x2f/0x114
[90496.171221] [<ffffffff8106479a>] ? wake_up_process+0x2f/0x32
[90496.172867] [<ffffffff81062c3b>] ? get_parent_ip+0xd/0x3c
[90496.174472] [<ffffffff81062ce5>] ? preempt_count_add+0x7b/0x8e
[90496.176053] [<ffffffff814717f3>] __wait_for_common+0x11e/0x163
[90496.177619] [<ffffffff814717f3>] ? __wait_for_common+0x11e/0x163
[90496.179173] [<ffffffff810647aa>] ? wake_up_state+0xd/0xd
[90496.180728] [<ffffffff81471857>] wait_for_completion+0x1f/0x21
[90496.182285] [<ffffffffc044e3b3>] btrfs_async_run_delayed_refs+0xbf/0xd9 [btrfs]
[90496.183833] [<ffffffffc04624e1>] __btrfs_end_transaction+0x2b6/0x2ec [btrfs]
[90496.185380] [<ffffffffc0462522>] btrfs_end_transaction+0xb/0xd [btrfs]
[90496.186940] [<ffffffffc0451742>] find_free_extent+0x8a9/0x976 [btrfs]
[90496.189464] [<ffffffffc0451990>] btrfs_reserve_extent+0x6f/0x119 [btrfs]
[90496.191326] [<ffffffffc0466b45>] cow_file_range+0x1a6/0x377 [btrfs]
[90496.193080] [<ffffffffc047adc4>] ? extent_write_locked_range+0x10c/0x11e [btrfs]
[90496.194659] [<ffffffffc04677e4>] submit_compressed_extents+0x100/0x412 [btrfs]
[90496.196225] [<ffffffff8120e344>] ? debug_smp_processor_id+0x17/0x19
[90496.197776] [<ffffffffc0467b78>] async_cow_submit+0x82/0x87 [btrfs]
[90496.199383] [<ffffffffc048644b>] normal_work_helper+0x153/0x224 [btrfs]
[90496.200944] [<ffffffff81052d8c>] process_one_work+0x16f/0x2b8
[90496.202483] [<ffffffff81053636>] worker_thread+0x27b/0x32e
[90496.204000] [<ffffffff810533bb>] ? cancel_delayed_work_sync+0x10/0x10
[90496.205514] [<ffffffff81058012>] kthread+0xb2/0xba
[90496.207040] [<ffffffff81470000>] ? ap_handle_dropped_data+0xf/0xc8
[90496.208565] [<ffffffff81057f60>] ? __kthread_parkme+0x62/0x62
[90496.210096] [<ffffffff81473f6c>] ret_from_fork+0x7c/0xb0
[90496.211618] [<ffffffff81057f60>] ? __kthread_parkme+0x62/0x62
Ok, this should explain the hang. submit_compressed_extents is calling
cow_file_range with a locked page.
cow_file_range is trying to find a free extent and in the process is
calling btrfs_end_transaction, which is running the async delayed refs,
which is trying to write dirty pages, which is waiting for your locked
page.
I should be able to reproduce this ;)
-chris
next prev parent reply other threads:[~2014-08-06 15:18 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-24 14:48 [PATCH] Btrfs: fix compressed write corruption on enospc Liu Bo
2014-07-24 14:55 ` Chris Mason
2014-07-25 1:00 ` Liu Bo
2014-07-25 9:58 ` Martin Steigerwald
2014-07-25 1:53 ` Wang Shilong
2014-07-25 2:08 ` Liu Bo
2014-07-25 2:11 ` Wang Shilong
2014-07-25 9:54 ` Martin Steigerwald
2014-08-04 12:50 ` Martin Steigerwald
2014-08-04 12:52 ` Martin Steigerwald
2014-08-06 10:21 ` Martin Steigerwald
2014-08-06 10:29 ` Hugo Mills
2014-08-06 12:28 ` Martin Steigerwald
2014-08-06 13:35 ` Chris Mason
2014-08-06 14:43 ` Martin Steigerwald
2014-08-06 15:18 ` Chris Mason [this message]
2014-08-07 0:52 ` Chris Mason
2014-08-07 7:50 ` Liu Bo
2014-08-07 8:20 ` Miao Xie
2014-08-07 14:02 ` Chris Mason
2014-08-10 14:55 ` Liu Bo
2014-08-11 20:35 ` Chris Mason
2014-08-12 2:55 ` Miao Xie
2014-08-12 7:51 ` Liu Bo
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