diff options
| author | FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | 2008-07-31 13:31:33 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-08-06 09:03:11 -0700 |
| commit | c4ec1c369322fc6dd1512975e11d2d2abe90a705 (patch) | |
| tree | 987d1cd03dc1823a5d0439c92368cd204e4d1474 /block | |
| parent | 16ace6872d0191fdbd764102b46e175c95b67b66 (diff) | |
SCSI: bsg: fix bsg_mutex hang with device removal
commit 3f27e3ed11e67c5ee19d560a50eafd93cf8c6682 upstream
[SCSI] bsg: fix bsg_mutex hang with device removal
We don't need to hold bsg_mutex during bsg_complete_all_commands(). It
leads to a problem that we block bsg_unregister_queue during
bsg_complete_all_commands (untill all the outstanding commands
complete).
Thanks to Pete Wyckoff for finding the bug and testing the patch.
The detailed bug report is:
http://marc.info/?l=linux-scsi&m=121182137132145&w=2
Tested-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
CC: Oliver Pinter <oliver.pntr@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'block')
| -rw-r--r-- | block/bsg.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/block/bsg.c b/block/bsg.c index 54d617f7df3e..052647150fa2 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -725,8 +725,13 @@ static int bsg_put_device(struct bsg_device *bd) mutex_lock(&bsg_mutex); do_free = atomic_dec_and_test(&bd->ref_count); - if (!do_free) + if (!do_free) { + mutex_unlock(&bsg_mutex); goto out; + } + + hlist_del(&bd->dev_list); + mutex_unlock(&bsg_mutex); dprintk("%s: tearing down\n", bd->name); @@ -742,10 +747,8 @@ static int bsg_put_device(struct bsg_device *bd) */ ret = bsg_complete_all_commands(bd); - hlist_del(&bd->dev_list); kfree(bd); out: - mutex_unlock(&bsg_mutex); kref_put(&q->bsg_dev.ref, bsg_kref_release_function); if (do_free) blk_put_queue(q); |