Hello Filipe, 2013/12/14 Filipe David Borba Manana <fdman...@gmail.com>: > Wang Shilong got into a case where during inode eviction we were > removing an extent map while it was pinned. This triggered a warning > in remove_extent_mapping() because the extent map had the pinned > flag set: > > [ 1209.102076] [<ffffffffa04721b9>] remove_extent_mapping+0x69/0x70 [btrfs] > [ 1209.102084] [<ffffffffa0466b06>] btrfs_evict_inode+0x96/0x4d0 [btrfs] > [ 1209.102089] [<ffffffff81073010>] ? wake_atomic_t_function+0x40/0x40 > [ 1209.102092] [<ffffffff8118ab2e>] evict+0x9e/0x190 > [ 1209.102094] [<ffffffff8118b313>] iput+0xf3/0x180 > [ 1209.102101] [<ffffffffa0461fd1>] btrfs_run_delayed_iputs+0xb1/0xd0 [btrfs] > [ 1209.102107] [<ffffffffa045d358>] __btrfs_end_transaction+0x268/0x350 > [btrfs] > > Therefore wait for any pending ordered extents, if any, which will > trigger calls to unpin_extent_cache(), before removing the extent maps. > > Wang's solution of simply clearing the pinned bit wasn't enough, as after > unpin_extent_cache() will be called and trigger another WARN_ON() because > the lookup for the extent map returned NULL.
Why not in evict_inode_truncate_pages() move remove_extent_mapping() after clear_extent_bit()? Thanks, Wang > > Thanks Wang for finding out this. > > Signed-off-by: Filipe David Borba Manana <fdman...@gmail.com> > --- > fs/btrfs/inode.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index e889779..c2933fb 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -4509,6 +4509,9 @@ static void evict_inode_truncate_pages(struct inode > *inode) > ASSERT(inode->i_state & I_FREEING); > truncate_inode_pages(&inode->i_data, 0); > > + /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ > + btrfs_wait_ordered_range(inode, 0, (u64)-1); > + > write_lock(&map_tree->lock); > while (!RB_EMPTY_ROOT(&map_tree->map)) { > struct extent_map *em; > @@ -4566,8 +4569,6 @@ void btrfs_evict_inode(struct inode *inode) > btrfs_orphan_del(NULL, inode); > goto no_delete; > } > - /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ > - btrfs_wait_ordered_range(inode, 0, (u64)-1); > > if (root->fs_info->log_root_recovering) { > BUG_ON(test_bit(BTRFS_INODE_HAS_ORPHAN_ITEM, > -- > 1.7.9.5 > > -- > 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 -- 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