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From:   Namjae Jeon <linkinjeon@kernel.org>
Date:   Tue, 21 Dec 2021 21:02:14 +0900
Message-ID: <CAKYAXd8pCfUBPRXT-44N_g2GD_BKtjboiepgTGz5DQ93YEiz-A@mail.gmail.com>
Subject: Re: [PATCH] ksmbd: use F_SETLK to force vfs_file_lock() to return asynchronously
To:     Vasily Averin <vvs@virtuozzo.com>
Cc:     Sergey Senozhatsky <senozhatsky@chromium.org>,
        Steve French <sfrench@samba.org>,
        Hyunchul Lee <hyc.lee@gmail.com>, kernel@openvz.org,
        linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org
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2021-12-19 18:34 GMT+09:00, Vasily Averin <vvs@virtuozzo.com>:
> To avoid possible deadlock ksmbd should process locks asynchronously.
> Callers expecting vfs_file_locks() to return asynchronously should only
> use F_SETLK, not F_SETLKW.
Should I check this patch instead of
[PATCH] ksmbd: force "fail immediately" flag on fs with its own ->lock ?

>
> Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
> ---
>  fs/ksmbd/smb2pdu.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index 0c020deb76bb..34f333549767 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -6646,13 +6646,13 @@ static int smb2_set_flock_flags(struct file_lock
> *flock, int flags)
>  	switch (flags) {
>  	case SMB2_LOCKFLAG_SHARED:
>  		ksmbd_debug(SMB, "received shared request\n");
> -		cmd = F_SETLKW;
> +		cmd = F_SETLK;
>  		flock->fl_type = F_RDLCK;
>  		flock->fl_flags |= FL_SLEEP;
>  		break;
>  	case SMB2_LOCKFLAG_EXCLUSIVE:
>  		ksmbd_debug(SMB, "received exclusive request\n");
> -		cmd = F_SETLKW;
> +		cmd = F_SETLK;
>  		flock->fl_type = F_WRLCK;
>  		flock->fl_flags |= FL_SLEEP;
>  		break;
> --
> 2.25.1
>
>