Re: [PATCH] xfs: Use WARN_ON rather than BUG() for bailout mount-operation

From: Christoph Hellwig
Date: Thu Aug 29 2019 - 04:18:27 EST


On Wed, Aug 28, 2019 at 03:47:49PM +0900, Austin Kim wrote:
> If the CONFIG_BUG is enabled, BUG() is executed and then system is crashed.
> However, the bailout for mount is no longer proceeding.
>
> For this reason, using WARN_ON rather than BUG() could prevent this situation.
> ---
> fs/xfs/xfs_mount.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
> index 322da69..10fe000 100644
> --- a/fs/xfs/xfs_mount.c
> +++ b/fs/xfs/xfs_mount.c
> @@ -213,8 +213,7 @@ xfs_initialize_perag(
> goto out_hash_destroy;
>
> spin_lock(&mp->m_perag_lock);
> - if (radix_tree_insert(&mp->m_perag_tree, index, pag)) {
> - BUG();
> + if (WARN_ON(radix_tree_insert(&mp->m_perag_tree, index, pag))){

Please make this a WARN_ON_ONCE so that we don't see a flodding of
messages in case of this error.