Re: [PATCH v2] libceph: init the cursor when preparing the sparse read

[Luis Henriques <lhenriques@suse.de>]

xiubli@redhat.com writes:

> From: Xiubo Li <xiubli@redhat.com>
>
> The osd code has remove cursor initilizing code and this will make
> the sparse read state into a infinite loop. We should initialize
> the cursor just before each sparse-read in messnger v2.
>
> Cc: stable@vger.kernel.org
> URL: https://tracker.ceph.com/issues/64607
> Fixes: 8e46a2d068c9 ("libceph: just wait for more data to be available on the socket")
> Reported-by: Luis Henriques <lhenriques@suse.de>
> Signed-off-by: Xiubo Li <xiubli@redhat.com>
> ---
>
> V2:
> - Just removed the unnecessary 'sparse_read_total' check.
>

Thanks a lot for the quick fix, Xiubo.  FWIW:

Tested-by: Luis Henriques <lhenriques@suse.de>

Note that I still see this test failing occasionally, but I haven't had
time to help debugging it.  And that's a different issue, of course.  TBH
I don't remember if this test ever used to reliably pass.  Here's the
output diff shown by fstests in case you're not able to reproduce it:

@@ -65,7 +65,7 @@
 # Getting encryption key status
 Present (user_count=1, added_by_self)
 # Removing encryption key
-Removed encryption key with identifier 69b2f6edeee720cce0577937eb8a6751
+Removed encryption key with identifier 69b2f6edeee720cce0577937eb8a6751, but files still busy
 # Getting encryption key status
 Absent
 # Verifying that the encrypted directory was "locked"

Cheers,
-- 
Luís

>
> net/ceph/messenger_v2.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/net/ceph/messenger_v2.c b/net/ceph/messenger_v2.c
> index a0ca5414b333..ab3ab130a911 100644
> --- a/net/ceph/messenger_v2.c
> +++ b/net/ceph/messenger_v2.c
> @@ -2034,6 +2034,9 @@ static int prepare_sparse_read_data(struct ceph_connection *con)
>  	if (!con_secure(con))
>  		con->in_data_crc = -1;
>  
> +	ceph_msg_data_cursor_init(&con->v2.in_cursor, con->in_msg,
> +				  con->in_msg->sparse_read_total);
> +
>  	reset_in_kvecs(con);
>  	con->v2.in_state = IN_S_PREPARE_SPARSE_DATA_CONT;
>  	con->v2.data_len_remain = data_len(msg);
> -- 
>
> 2.43.0
>