From bf67802453d3ebe1a9bcead9201d48f8c97f0f5a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Wed, 2 Aug 2023 09:20:24 -0400 Subject: [PATCH] btrfs: set cache_block_group_error if we find an error commit 92fb94b69c6accf1e49fff699640fa0ce03dc910 upstream. We set cache_block_group_error if btrfs_cache_block_group() returns an error, this is because we could end up not finding space to allocate and mistakenly return -ENOSPC, and which could then abort the transaction with the incorrect errno, and in the case of ENOSPC result in a WARN_ON() that will trip up tests like generic/475. However there's the case where multiple threads can be racing, one thread gets the proper error, and the other thread doesn't actually call btrfs_cache_block_group(), it instead sees ->cached == BTRFS_CACHE_ERROR. Again the result is the same, we fail to allocate our space and return -ENOSPC. Instead we need to set cache_block_group_error to -EIO in this case to make sure that if we do not make our allocation we get the appropriate error returned back to the caller. CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/extent-tree.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 571fcc5ae4dcf..f2ee70c03f0d5 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4411,8 +4411,11 @@ static noinline int find_free_extent(struct btrfs_root *root, ret = 0; } - if (unlikely(block_group->cached == BTRFS_CACHE_ERROR)) + if (unlikely(block_group->cached == BTRFS_CACHE_ERROR)) { + if (!cache_block_group_error) + cache_block_group_error = -EIO; goto loop; + } bg_ret = NULL; ret = do_allocation(block_group, ffe_ctl, &bg_ret);