From mboxrd@z Thu Jan  1 00:00:00 1970
From: Laszlo Ersek <lersek@redhat.com>
Subject: [PATCH linux-2.6.18-xen] fix xenbus_transaction_start()
 hang caused by double xenbus_transaction_end()
Date: Thu, 12 May 2011 12:24:17 +0200
Message-ID: <4DCBB551.7000002@redhat.com>
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Cc: Ky Srinivasan <ksrinivasan@novell.com>
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fix xenbus_transaction_start() hang caused by double xenbus_transaction_end()

vbd_resize() up_read()'s xs_state.suspend_mutex twice in a row via double
xenbus_transaction_end() calls. The next down_read() in
xenbus_transaction_start() (at eg. the next resize attempt) hangs.

See RHBZ#618317.

Thanks for considering.

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---
 drivers/xen/blkback/vbd.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/xen/blkback/vbd.c b/drivers/xen/blkback/vbd.c
--- a/drivers/xen/blkback/vbd.c
+++ b/drivers/xen/blkback/vbd.c
@@ -156,6 +156,7 @@
 		goto again;
 	if (err)
 		printk(KERN_WARNING "Error ending transaction");
+	return;
 abort:
 	xenbus_transaction_end(xbt, 1);
 }