From: Ilya Dryomov <idryomov@gmail.com>
Date: Tue, 1 Aug 2023 19:14:24 +0200
Subject: libceph: fix potential hang in ceph_osdc_notify()
Git-commit: e6e2843230799230fc5deb8279728a7218b0d63c
Patch-mainline: v6.5-rc5
References: bsc#1214752
If the cluster becomes unavailable, ceph_osdc_notify() may hang even
with osd_request_timeout option set because linger_notify_finish_wait()
waits for MWatchNotify NOTIFY_COMPLETE message with no associated OSD
request in flight -- it's completely asynchronous.
Introduce an additional timeout, derived from the specified notify
timeout. While at it, switch both waits to killable which is more
correct.
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Acked-by: Luís Henriques <lhenriques@suse.de>
---
net/ceph/osd_client.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 11c04e7d928e..658a6f2320cf 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -3334,17 +3334,24 @@ static int linger_reg_commit_wait(struct ceph_osd_linger_request *lreq)
int ret;
dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
- ret = wait_for_completion_interruptible(&lreq->reg_commit_wait);
+ ret = wait_for_completion_killable(&lreq->reg_commit_wait);
return ret ?: lreq->reg_commit_error;
}
-static int linger_notify_finish_wait(struct ceph_osd_linger_request *lreq)
+static int linger_notify_finish_wait(struct ceph_osd_linger_request *lreq,
+ unsigned long timeout)
{
- int ret;
+ long left;
dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
- ret = wait_for_completion_interruptible(&lreq->notify_finish_wait);
- return ret ?: lreq->notify_finish_error;
+ left = wait_for_completion_killable_timeout(&lreq->notify_finish_wait,
+ ceph_timeout_jiffies(timeout));
+ if (left <= 0)
+ left = left ?: -ETIMEDOUT;
+ else
+ left = lreq->notify_finish_error; /* completed */
+
+ return left;
}
/*
@@ -4896,7 +4903,8 @@ int ceph_osdc_notify(struct ceph_osd_client *osdc,
linger_submit(lreq);
ret = linger_reg_commit_wait(lreq);
if (!ret)
- ret = linger_notify_finish_wait(lreq);
+ ret = linger_notify_finish_wait(lreq,
+ msecs_to_jiffies(2 * timeout * MSEC_PER_SEC));
else
dout("lreq %p failed to initiate notify %d\n", lreq, ret);