4.19-stable review patch. If anyone has any objections, please let me know.
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From: Anand Jain anand.jain@oracle.com
commit 05c49e6bc1e8866ecfd674ebeeb58cdbff9145c2 upstream.
In a secnario where balance and replace co-exists as below,
- start balance - pause balance - start replace - reboot
and when system restarts, balance resumes first. Then the replace is attempted to restart but will fail as the EXCL_OP lock is already held by the balance. If so place the replace state back to BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state.
Fixes: 010a47bde9420 ("btrfs: add proper safety check before resuming dev-replace") CC: stable@vger.kernel.org # 4.18+ Signed-off-by: Anand Jain anand.jain@oracle.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/dev-replace.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -900,6 +900,10 @@ int btrfs_resume_dev_replace_async(struc * dev-replace to start anyway. */ if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { + btrfs_dev_replace_write_lock(dev_replace); + dev_replace->replace_state = + BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; + btrfs_dev_replace_write_unlock(dev_replace); btrfs_info(fs_info, "cannot resume dev-replace, other exclusive operation running"); return 0;