From: Bob Liu <bob.liu@oracle.com>
To: xen-devel@lists.xenproject.org
Cc: Bob Liu <bob.liu@oracle.com>,
linux-kernel@vger.kernel.org, roger.pau@citrix.com
Subject: [PATCH] block: xen-blkback: don't get/put blkif ref for each queue
Date: Mon, 26 Sep 2016 15:36:24 +0800 [thread overview]
Message-ID: <1474875384-24671-1-git-send-email-bob.liu__23509.1100483716$1474875467$gmane$org@oracle.com> (raw)
xen_blkif_get/put() for each queue is useless, and introduces a bug:
If there is I/O inflight when removing device, xen_blkif_disconnect() will
return -EBUSY and xen_blkif_put() not be called.
Which means the references are leaked, then even if I/O completed, the
xen_blkif_put() won't call xen_blkif_deferred_free() to free resources anymore.
Signed-off-by: Bob Liu <bob.liu@oracle.com>
---
drivers/block/xen-blkback/xenbus.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 3cc6d1d..2e1bb6d 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -159,7 +159,6 @@ static int xen_blkif_alloc_rings(struct xen_blkif *blkif)
init_waitqueue_head(&ring->shutdown_wq);
ring->blkif = blkif;
ring->st_print = jiffies;
- xen_blkif_get(blkif);
}
return 0;
@@ -296,7 +295,6 @@ static int xen_blkif_disconnect(struct xen_blkif *blkif)
BUG_ON(ring->free_pages_num != 0);
BUG_ON(ring->persistent_gnt_c != 0);
WARN_ON(i != (XEN_BLKIF_REQS_PER_PAGE * blkif->nr_ring_pages));
- xen_blkif_put(blkif);
}
blkif->nr_ring_pages = 0;
/*
--
1.7.10.4
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next reply other threads:[~2016-09-26 7:36 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-26 7:36 Bob Liu [this message]
[not found] <1474875384-24671-1-git-send-email-bob.liu@oracle.com>
2016-09-26 14:14 ` [PATCH] block: xen-blkback: don't get/put blkif ref for each queue Konrad Rzeszutek Wilk
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