From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: [PATCH 09/11] xen/hvm kexec: unregister the watch of the "device" node during reboot Date: Thu, 28 Jul 2011 15:23:09 +0200 Message-ID: <20110728132303.107520996@aepfle.de> References: <20110728132300.248098023@aepfle.de> Return-path: Content-Disposition: inline; filename=xen.syscore_ops.unregister_watch.xenbus_frontend.patch List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org The watch of the xenstore "device" node has to be unregistered during a kexec reboot. Otherwise the kexec kernel will crash due to a memory corruption because more than one watch is registered on that node. v2: use kexec_is_loaded() function Signed-off-by: Olaf Hering --- drivers/xen/xenbus/xenbus_probe_frontend.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) Index: linux-3.0/drivers/xen/xenbus/xenbus_probe_frontend.c =================================================================== --- linux-3.0.orig/drivers/xen/xenbus/xenbus_probe_frontend.c +++ linux-3.0/drivers/xen/xenbus/xenbus_probe_frontend.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include #include #include @@ -263,6 +265,18 @@ static int frontend_probe_and_watch(stru return NOTIFY_DONE; } +static void xenbus_frontend_shutdown_watcher(void) +{ + if (!kexec_is_loaded()) + return; + + unregister_xenbus_watch(&fe_watch); +} + +static struct syscore_ops xenbus_frontend_watcher_syscore_ops = { + .shutdown = xenbus_frontend_shutdown_watcher, +}; + static int __init xenbus_probe_frontend_init(void) { @@ -279,6 +293,7 @@ static int __init xenbus_probe_frontend_ return err; register_xenstore_notifier(&xenstore_notifier); + register_syscore_ops(&xenbus_frontend_watcher_syscore_ops); return 0; }