On Wed, Jul 01, 2020 at 08:59:23PM -0400, Waiman Long wrote:
> Suggested-by: Dave Chinner <david@xxxxxxxxxxxxx>
> Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
> ---
> fs/xfs/xfs_super.c | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 379cbff438bc..dcc97bad950a 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -913,11 +913,21 @@ xfs_fs_freeze(
> struct super_block *sb)
> {
> struct xfs_mount *mp = XFS_M(sb);
> + unsigned long pflags;
> + int ret;
>
> + /*
> + * Disable fs reclaim in memory allocation for fs freeze to avoid
> + * causing a possible circular locking dependency lockdep splat
> + * relating to fs reclaim.
> + */
/*
* The filesystem is now frozen far enough that memory reclaim
* cannot safely operate on the filesystem. Hence we need to
* set a GFP_NOFS context here to avoid recursion deadlocks.
*/
> + current_set_flags_nested(&pflags, PF_MEMALLOC_NOFS);
memalloc_nofs_save/restore(), please.
-Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx
