From: Josef Bacik Date: Tue, 23 Jul 2013 20:57:15 +0000 (-0400) Subject: Btrfs: cleanup reloc roots properly on error X-Git-Tag: v3.12-rc2~5^2~127 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b37b39cd6b8af7a7c39fc7340d71f3db492af9e2;p=profile%2Fivi%2Fkernel-x86-ivi.git Btrfs: cleanup reloc roots properly on error I was hitting the BUG_ON() at the end of merge_reloc_roots() because we were aborting the transaction at some point previously and then getting an error when we tried to drop the reloc root. I fixed btrfs_drop_snapshot to re-add us to the dead roots list if we failed, but this isn't the right thing to do for reloc roots since it uses root->root_list for it's own stuff in order to know what needs to be cleaned up. So fix btrfs_drop_snapshot to only do the re-add if we aren't dropping for reloc, and handle errors from merge_reloc_root() by dropping the reloc root we are processing since it won't be on the list of roots to cleanup. With this patch my reproducer no longer panics. Thanks, Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index ca02d3c..e868c35 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7696,7 +7696,7 @@ out: * don't have it in the radix (like when we recover after a power fail * or unmount) so we don't leak memory. */ - if (root_dropped == false) + if (!for_reloc && root_dropped == false) btrfs_add_dead_root(root); if (err) btrfs_std_error(root->fs_info, err); diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 295a611..5a23d87 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -2314,8 +2314,13 @@ again: BUG_ON(root->reloc_root != reloc_root); ret = merge_reloc_root(rc, root); - if (ret) + if (ret) { + __update_reloc_root(reloc_root, 1); + free_extent_buffer(reloc_root->node); + free_extent_buffer(reloc_root->commit_root); + kfree(reloc_root); goto out; + } } else { list_del_init(&reloc_root->root_list); }