diff options
| author |   Weston Andros Adamson <dros@primarydata.com> | 2014-01-21 15:21:33 -0500 |
|---|---|---|
| committer |   Trond Myklebust <trond.myklebust@primarydata.com> | 2014-01-21 14:12:18 -0700 |
| commit | 471252cd8b34b0609973740b25dcd1ff01dc1889 (patch) | |
| tree | 392de168d98cfa7ca804eb1dafbeefd7dc0cdbd9 /fs/nfs | |
| parent | nfs4: fix discover_server_trunking use after free (diff) | |
| download | linux-dev-471252cd8b34b0609973740b25dcd1ff01dc1889.tar.xz linux-dev-471252cd8b34b0609973740b25dcd1ff01dc1889.zip | |
pnfs: fix BUG in filelayout_recover_commit_reqs
cond_resched_lock(cinfo->lock) is called everywhere else while holding
the cinfo->lock spinlock. Not holding this lock while calling
transfer_commit_list in filelayout_recover_commit_reqs causes the BUG
below.
It's true that we can't hold this lock while calling pnfs_put_lseg,
because that might try to lock the inode lock - which might be the
same lock as cinfo->lock.
To reproduce, mount a 2 DS pynfs server and run an O_DIRECT command
that crosses a stripe boundary and is not page aligned, such as:
dd if=/dev/zero of=/mnt/f bs=17000 count=1 oflag=direct
BUG: sleeping function called from invalid context at linux/fs/nfs/nfs4filelayout.c:1161
in_atomic(): 0, irqs_disabled(): 0, pid: 27, name: kworker/0:1
2 locks held by kworker/0:1/27:
#0: (events){.+.+.+}, at: [<ffffffff810501d7>] process_one_work+0x175/0x3a5
#1: ((&dreq->work)){+.+...}, at: [<ffffffff810501d7>] process_one_work+0x175/0x3a5
CPU: 0 PID: 27 Comm: kworker/0:1 Not tainted 3.13.0-rc3-branch-dros_testing+ #21
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013
Workqueue: events nfs_direct_write_schedule_work [nfs]
0000000000000000 ffff88007a39bbb8 ffffffff81491256 ffff88007b87a130 ffff88007a39bbd8 ffffffff8105f103 ffff880079614000 ffff880079617d40 ffff88007a39bc20 ffffffffa011603e ffff880078988b98 0000000000000000
Call Trace:
[<ffffffff81491256>] dump_stack+0x4d/0x66
[<ffffffff8105f103>] __might_sleep+0x100/0x105
[<ffffffffa011603e>] transfer_commit_list+0x94/0xf1 [nfs_layout_nfsv41_files]
[<ffffffffa01160d6>] filelayout_recover_commit_reqs+0x3b/0x68 [nfs_layout_nfsv41_files]
[<ffffffffa00ba53a>] nfs_direct_write_reschedule+0x9f/0x1d6 [nfs]
[<ffffffff810705df>] ? mark_lock+0x1df/0x224
[<ffffffff8106e617>] ? trace_hardirqs_off_caller+0x37/0xa4
[<ffffffff8106e691>] ? trace_hardirqs_off+0xd/0xf
[<ffffffffa00ba8f8>] nfs_direct_write_schedule_work+0x9d/0xb7 [nfs]
[<ffffffff810501d7>] ? process_one_work+0x175/0x3a5
[<ffffffff81050258>] process_one_work+0x1f6/0x3a5
[<ffffffff810501d7>] ? process_one_work+0x175/0x3a5
[<ffffffff8105187e>] worker_thread+0x149/0x1f5
[<ffffffff81051735>] ? rescuer_thread+0x28d/0x28d
[<ffffffff81056d74>] kthread+0xd2/0xda
[<ffffffff81056ca2>] ? __kthread_parkme+0x61/0x61
[<ffffffff8149e66c>] ret_from_fork+0x7c/0xb0
[<ffffffff81056ca2>] ? __kthread_parkme+0x61/0x61
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'fs/nfs')
| -rw-r--r-- | fs/nfs/nfs4filelayout.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c index 0a93e798df3a..03fd8be8c0c5 100644 --- a/fs/nfs/nfs4filelayout.c +++ b/fs/nfs/nfs4filelayout.c @@ -1216,17 +1216,17 @@ static void filelayout_recover_commit_reqs(struct list_head *dst, struct pnfs_commit_bucket *b; int i; - /* NOTE cinfo->lock is NOT held, relying on fact that this is - * only called on single thread per dreq. - * Can't take the lock because need to do pnfs_put_lseg - */ + spin_lock(cinfo->lock); for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) { if (transfer_commit_list(&b->written, dst, cinfo, 0)) { + spin_unlock(cinfo->lock); pnfs_put_lseg(b->wlseg); b->wlseg = NULL; + spin_lock(cinfo->lock); } } cinfo->ds->nwritten = 0; + spin_unlock(cinfo->lock); } static unsigned int |