From a947f0f8f7012a5e8689a9cff7209ec6964ec154 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Mon, 4 Oct 2010 16:10:06 +0100 Subject: [PATCH] xen: do not set xenstored_ready before xenbus_probe on hvm Register_xenstore_notifier should guarantee that the caller gets notified even if xenstore is already up. Therefore we revert "do not notify callers from register_xenstore_notifier" and set xenstored_read at the right time for PV on HVM guests too. In fact in case of PV on HVM guests xenstored is ready only after the platform pci driver has completed the initialization, so do not set xenstored_ready before the call to xenbus_probe(). This patch fixes a shutdown_event watcher registration bug that causes "xm shutdown" not to work properly. Signed-off-by: Stefano Stabellini Acked-by: Jeremy Fitzhardinge --- drivers/xen/xenbus/xenbus_probe.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index 29bac5118877..d409495876f1 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -755,7 +755,10 @@ int register_xenstore_notifier(struct notifier_block *nb) { int ret = 0; - blocking_notifier_chain_register(&xenstore_chain, nb); + if (xenstored_ready > 0) + ret = nb->notifier_call(nb, 0, NULL); + else + blocking_notifier_chain_register(&xenstore_chain, nb); return ret; } @@ -769,7 +772,7 @@ EXPORT_SYMBOL_GPL(unregister_xenstore_notifier); void xenbus_probe(struct work_struct *unused) { - BUG_ON((xenstored_ready <= 0)); + xenstored_ready = 1; /* Enumerate devices in xenstore and watch for changes. */ xenbus_probe_devices(&xenbus_frontend); @@ -835,8 +838,8 @@ static int __init xenbus_init(void) xen_store_evtchn = xen_start_info->store_evtchn; xen_store_mfn = xen_start_info->store_mfn; xen_store_interface = mfn_to_virt(xen_store_mfn); + xenstored_ready = 1; } - xenstored_ready = 1; } /* Initialize the interface to xenstore. */