On Thu, Mar 26, 2015 at 3:24 AM, Eric Sandeen <sand...@redhat.com> wrote: > Looks like "btrfs: fix leak of path in btrfs_find_item" got sent > to stable trees, but in my testing, it causes deadlocks on mount: > > [23379.359246] mount D 0000000000000000 0 22541 22274 > 0x00000080 > [23379.366326] ffff8803ebadf6c8 0000000000000086 ffff88027ff10230 > 0000000000013680 > [23379.373770] 0000000000013680 ffff8803ebadffd8 ffff8803ebadc010 > 0000000000013680 > [23379.381208] ffff8803ebadffd8 0000000000013680 ffff880261c78b60 > ffff8802140a0b60 > [23379.388648] Call Trace: > [23379.391106] [<ffffffff816182b9>] schedule+0x29/0x70 > [23379.396091] [<ffffffffa06b82f5>] btrfs_tree_lock+0xb5/0x290 [btrfs] > [23379.402444] [<ffffffff8109b470>] ? wake_up_bit+0x40/0x40 > [23379.407855] [<ffffffffa064f7a5>] ? generic_bin_search+0xf5/0x180 [btrfs] > [23379.414643] [<ffffffffa065041b>] btrfs_lock_root_node+0x3b/0x50 [btrfs] > [23379.421345] [<ffffffffa065936b>] btrfs_search_slot+0x63b/0x800 [btrfs] > [23379.427956] [<ffffffffa064fa49>] ? btrfs_set_path_blocking+0x39/0x80 > [btrfs] > [23379.435088] [<ffffffffa0659ede>] btrfs_insert_empty_items+0x7e/0xe0 > [btrfs] > [23379.442125] [<ffffffffa065051a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs] > [23379.448655] [<ffffffffa06b8989>] btrfs_insert_orphan_item+0x69/0x90 > [btrfs] > [23379.455696] [<ffffffffa06ba938>] insert_orphan_item+0x68/0x90 [btrfs] > [23379.462251] [<ffffffffa06bf772>] replay_one_buffer+0x372/0x380 [btrfs] > [23379.468878] [<ffffffffa069a4c1>] ? mark_extent_buffer_accessed+0x51/0x70 > [btrfs] > [23379.476372] [<ffffffffa06ba54b>] walk_up_log_tree+0x1cb/0x250 [btrfs] > [23379.482910] [<ffffffffa06ba68f>] walk_log_tree+0xbf/0x1b0 [btrfs] > [23379.489098] [<ffffffffa06bd51c>] btrfs_recover_log_trees+0x1ec/0x4c0 > [btrfs] > ... > > I could hit this by running ./check generic/015 generic/039 in fstests, > with a SCRATCH_DEV_POOL defined (not sure it matters, it's just what I > have...) > > This fixes it, though I'm not totally sure why. Refcounts?
Hi Eric, Your patch seems correct to me. The problem is that btrfs_insert_orphan_item tries to get a write lock on the same node/leaf for which its caller (insert_orphan_item) is already holding a read lock. If you plan to submit a proper patch, feel free to add my Reviewed-by: Filipe Manana <fdman...@suse.com> thanks > > diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c > index 906934e..d37e6d1 100644 > --- a/fs/btrfs/tree-log.c > +++ b/fs/btrfs/tree-log.c > @@ -1265,11 +1265,11 @@ static int insert_orphan_item(struct > btrfs_trans_handle *trans, > > ret = btrfs_find_item(root, path, BTRFS_ORPHAN_OBJECTID, > offset, BTRFS_ORPHAN_ITEM_KEY, NULL); > + btrfs_free_path(path); > + > if (ret > 0) > ret = btrfs_insert_orphan_item(trans, root, offset); > > - btrfs_free_path(path); > - > return ret; > } > > > but it never likely showed up upstream, because > > 9c4f61f btrfs: simplify insert_orphan_item > > made the whole path alloc/free go away. > > -Eric > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Filipe David Manana, "Reasonable men adapt themselves to the world. Unreasonable men adapt the world to themselves. That's why all progress depends on unreasonable men." -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
