Re: [PATCH 8/8] ceph: hold i_ceph_lock when removing caps for freeing inode

[Yan, Zheng]

On 5/29/19 9:14 PM, Sasha Levin wrote:
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: all
>
> The bot has tested the following trees: v5.1.4, v5.0.18, v4.19.45, v4.14.121, v4.9.178, v4.4.180, v3.18.140.
>
> v5.1.4: Build OK!
> v5.0.18: Failed to apply! Possible dependencies:
>      e3ec8d6898f71 ("ceph: send cap releases more aggressively")
>
> v4.19.45: Failed to apply! Possible dependencies:
>      e3ec8d6898f71 ("ceph: send cap releases more aggressively")
>
> v4.14.121: Failed to apply! Possible dependencies:
>      a1c6b8358171c ("ceph: define argument structure for handle_cap_grant")
>      a57d9064e4ee4 ("ceph: flush pending works before shutdown super")
>      e3ec8d6898f71 ("ceph: send cap releases more aggressively")
>
> v4.9.178: Failed to apply! Possible dependencies:
>      a1c6b8358171c ("ceph: define argument structure for handle_cap_grant")
>      a57d9064e4ee4 ("ceph: flush pending works before shutdown super")
>      e3ec8d6898f71 ("ceph: send cap releases more aggressively")
>
> v4.4.180: Failed to apply! Possible dependencies:
>      13d1ad16d05ee ("libceph: move message allocation out of ceph_osdc_alloc_request()")
>      34b759b4a22b0 ("ceph: kill ceph_empty_snapc")
>      3f1af42ad0fad ("libceph: enable large, variable-sized OSD requests")
>      5be0389dac662 ("ceph: re-send AIO write request when getting -EOLDSNAP error")
>      7627151ea30bc ("libceph: define new ceph_file_layout structure")
>      779fe0fb8e188 ("ceph: rados pool namespace support")
>      922dab6134178 ("libceph, rbd: ceph_osd_linger_request, watch/notify v2")
>      a1c6b8358171c ("ceph: define argument structure for handle_cap_grant")
>      ae458f5a171ba ("libceph: make r_request msg_size calculation clearer")
>      c41d13a31fefe ("rbd: use header_oid instead of header_name")
>      c8fe9b17d055f ("ceph: Asynchronous IO support")
>      d30291b985d18 ("libceph: variable-sized ceph_object_id")
>      e3ec8d6898f71 ("ceph: send cap releases more aggressively")
>
> v3.18.140: Failed to apply! Possible dependencies:
>      10183a69551f7 ("ceph: check OSD caps before read/write")
>      28127bdd2f843 ("ceph: convert inline data to normal data before data write")
>      31c542a199d79 ("ceph: add inline data to pagecache")
>      5be0389dac662 ("ceph: re-send AIO write request when getting -EOLDSNAP error")
>      70db4f3629b34 ("ceph: introduce a new inode flag indicating if cached dentries are ordered")
>      745a8e3bccbc6 ("ceph: don't pre-allocate space for cap release messages")
>      7627151ea30bc ("libceph: define new ceph_file_layout structure")
>      779fe0fb8e188 ("ceph: rados pool namespace support")
>      83701246aee8f ("ceph: sync read inline data")
>      a1c6b8358171c ("ceph: define argument structure for handle_cap_grant")
>      affbc19a68f99 ("ceph: make sure syncfs flushes all cap snaps")
>      c8fe9b17d055f ("ceph: Asynchronous IO support")
>      d30291b985d18 ("libceph: variable-sized ceph_object_id")
>      d3383a8e37f80 ("ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_sync)")
>      e3ec8d6898f71 ("ceph: send cap releases more aggressively")
>      e96a650a8174e ("ceph, rbd: delete unnecessary checks before two function calls")
>
>
> How should we proceed with this patch?

please use following patch for old kernels

Regards
Yan, Zheng

---
From 55937416f12e096621b06ada7554cacb89d06e97 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@xxxxxxxxxx>
Date: Thu, 23 May 2019 11:01:37 +0800
Subject: [PATCH] ceph: hold i_ceph_lock when removing caps for freeing inode

ceph_d_revalidate(, LOOKUP_RCU) may call __ceph_caps_issued_mask()
on a freeing inode.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: "Yan, Zheng" <zyan@xxxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
 fs/ceph/caps.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index ff5d32cf9578..0fb4e919cdce 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1119,20 +1119,23 @@ static int send_cap_msg(struct cap_msg_args *arg)
 }

 /*
- * Queue cap releases when an inode is dropped from our cache.  Since
- * inode is about to be destroyed, there is no need for i_ceph_lock.
+ * Queue cap releases when an inode is dropped from our cache.
  */
 void ceph_queue_caps_release(struct inode *inode)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct rb_node *p;

+	/* lock i_ceph_lock, because ceph_d_revalidate(..., LOOKUP_RCU)
+	 * may call __ceph_caps_issued_mask() on a freeing inode. */
+	spin_lock(&ci->i_ceph_lock);
 	p = rb_first(&ci->i_caps);
 	while (p) {
 		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
 		p = rb_next(p);
 		__ceph_remove_cap(cap, true);
 	}
+	spin_unlock(&ci->i_ceph_lock);
 }

 /*
--
2.17.2





> --
> Thanks,
> Sasha