Re: [RFC][PATCH 07/10] orangefs: Use RCU for destroy_inode

From: Al Viro
Date: Fri Feb 24 2017 - 15:52:49 EST


That, AFAICS, fixes a real bug. Applied, and it needs Cc:stable as well.


> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
> fs/orangefs/super.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> --- a/fs/orangefs/super.c
> +++ b/fs/orangefs/super.c
> @@ -115,6 +115,13 @@ static struct inode *orangefs_alloc_inod
> return &orangefs_inode->vfs_inode;
> }
>
> +static void orangefs_i_callback(struct rcu_head *head)
> +{
> + struct inode *inode = container_of(head, struct inode, i_rcu);
> + struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
> + kmem_cache_free(orangefs_inode_cache, orangefs_inode);
> +}
> +
> static void orangefs_destroy_inode(struct inode *inode)
> {
> struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
> @@ -123,7 +130,7 @@ static void orangefs_destroy_inode(struc
> "%s: deallocated %p destroying inode %pU\n",
> __func__, orangefs_inode, get_khandle_from_ino(inode));
>
> - kmem_cache_free(orangefs_inode_cache, orangefs_inode);
> + call_rcu(&inode->i_rcu, orangefs_i_callback);
> }
>
> /*
>
>