From 18d3bff411c8d46d40537483bdc0b61b33ce0371 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Wed, 16 Dec 2020 11:22:05 -0500 Subject: [PATCH] btrfs: don't get an EINTR during drop_snapshot for reloc This was partially fixed by f3e3d9cc3525 ("btrfs: avoid possible signal interruption of btrfs_drop_snapshot() on relocation tree"), however it missed a spot when we restart a trans handle because we need to end the transaction. The fix is the same, simply use btrfs_join_transaction() instead of btrfs_start_transaction() when deleting reloc roots. Fixes: f3e3d9cc3525 ("btrfs: avoid possible signal interruption of btrfs_drop_snapshot() on relocation tree") CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/extent-tree.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index d79b8369e6aa..30b1a630dc2f 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -5549,7 +5549,15 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc) goto out_free; } - trans = btrfs_start_transaction(tree_root, 0); + /* + * Use join to avoid potential EINTR from transaction + * start. See wait_reserve_ticket and the whole + * reservation callchain. + */ + if (for_reloc) + trans = btrfs_join_transaction(tree_root); + else + trans = btrfs_start_transaction(tree_root, 0); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_free;