Re: [PATCH] xfs: fix double mutex_lock() call in xfs_ioc_health_monitor()

[Darrick J. Wong]

On Thu, Sep 10, 2026 at 10:29:55PM +0900, Shigeru Yoshida wrote:
> Commit 4870da4f49ae ("xfs: take hm->lock in xfs_ioc_health_monitor()
> before insert") intended to protect the __xfs_healthmon_insert() call
> with hm->lock, but the second mutex operation was accidentally left as
> mutex_lock() instead of mutex_unlock(), causing self-deadlock. Change
> the second call to mutex_unlock() as originally intended.
> 
> Fixes: 4870da4f49ae ("xfs: take hm->lock in xfs_ioc_health_monitor() before insert")
> Signed-off-by: Shigeru Yoshida <syoshida@xxxxxxxxxx>

The original patch I reviewed unlocked hm->lock correctly, not sure how
it got corrupted by the tooling such that we need this.  I think cem
fixed it already(?) but in case anyone needs it,

Reviewed-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>

--D

> ---
>  fs/xfs/xfs_healthmon.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/xfs_healthmon.c b/fs/xfs/xfs_healthmon.c
> index 6dc3f69d6798..c3749675ef19 100644
> --- a/fs/xfs/xfs_healthmon.c
> +++ b/fs/xfs/xfs_healthmon.c
> @@ -1225,7 +1225,7 @@ xfs_ioc_health_monitor(
>  	running_event->domain = XFS_HEALTHMON_MOUNT;
>  	mutex_lock(&hm->lock);
>  	__xfs_healthmon_insert(hm, INSERT_HEAD, running_event);
> -	mutex_lock(&hm->lock);
> +	mutex_unlock(&hm->lock);
>  
>  	/*
>  	 * Preallocate the unmount event so that we can't fail to notify the
> -- 
> 2.55.0
> 
>