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Date:   Wed, 1 Apr 2020 12:01:25 +0200
From:   Jan Kara <jack@suse.cz>
To:     Jules Irenge <jbi.octave@gmail.com>
Cc:     linux-kernel@vger.kernel.org, boqun.feng@gmail.com,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Dan Williams <dan.j.williams@intel.com>,
        Matthew Wilcox <willy@infradead.org>, Jan Kara <jack@suse.cz>,
        "open list:FILESYSTEMS (VFS and infrastructure)" 
        <linux-fsdevel@vger.kernel.org>,
        "open list:FILESYSTEM DIRECT ACCESS (DAX)" 
        <linux-nvdimm@lists.01.org>
Subject: Re: [PATCH 3/7] dax: Add missing annotation for wait_entry_unlocked()
Message-ID: <20200401100125.GB19466@quack2.suse.cz>
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On Tue 31-03-20 21:46:39, Jules Irenge wrote:
> Sparse reports a warning at wait_entry_unlocked()
> 
> warning: context imbalance in wait_entry_unlocked()
> 	- unexpected unlock
> 
> The root cause is the missing annotation at wait_entry_unlocked()
> Add the missing __releases(xa) annotation.
> 
> Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
> ---
>  fs/dax.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/fs/dax.c b/fs/dax.c
> index 1f1f0201cad1..adcd2a57fbad 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -244,6 +244,7 @@ static void *get_unlocked_entry(struct xa_state *xas, unsigned int order)
>   * After we call xas_unlock_irq(), we cannot touch xas->xa.
>   */
>  static void wait_entry_unlocked(struct xa_state *xas, void *entry)
> +	__releases(xa)

Thanks for the patch but is this a proper sparse annotation? I'd rather
expect something like __releases(xas->xa->xa_lock) here...

								Honza

>  {
>  	struct wait_exceptional_entry_queue ewait;
>  	wait_queue_head_t *wq;
> -- 
> 2.24.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR