On 6/27/23 21:57, Milind Changire wrote:

On Tue, Jun 27, 2023 at 12:33 PM xiubli@redhat.com wrote:

...

From: Xiubo Li xiubli@redhat.com

If just before the revoke request, which will increase the 'seq', is sent out the clients released the corresponding caps and sent out the cap update request to MDS with old 'seq', the mds will miss checking the seqs and calculating the caps.

We should always send an ack for revoke requests.

I think the commit message needs to be rephrased for better understanding to something like:

If a client sends out a cap update request with the old 'seq' just before a pending cap revoke request, then the MDS might miscalculate the 'seqs' and caps. It's therefore always a good idea to ack the cap revoke request with the bumped up 'seq'.

Xiubo, please let me know if this sounds okay to you.

Milind,

Yeah, this looks much better.

I will update it.

Thanks

- Xiubo

...

Cc: stable@vger.kernel.org Cc: Patrick Donnelly pdonnell@redhat.com URL: https://tracker.ceph.com/issues/61782 Signed-off-by: Xiubo Li xiubli@redhat.com

---

fs/ceph/caps.c | 9 +++++++++ 1 file changed, 9 insertions(+)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 1052885025b3..eee2fbca3430 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -3737,6 +3737,15 @@ static void handle_cap_grant(struct inode *inode, } BUG_ON(cap->issued & ~cap->implemented);

•   /* don't let check_caps skip sending a response to MDS for revoke msgs */
  

•   if (le32_to_cpu(grant->op) == CEPH_CAP_OP_REVOKE) {
  

•           cap->mds_wanted = 0;
  

•           if (cap == ci->i_auth_cap)
  

•                   check_caps = 1; /* check auth cap only */
  

•           else
  

•                   check_caps = 2; /* check all caps */
  

•   }
  

•    if (extra_info->inline_version > 0 &&
         extra_info->inline_version >= ci->i_inline_version) {
             ci->i_inline_version = extra_info->inline_version;
  

-- 2.40.1