From: Julien Grall jgrall@amazon.com
commit c4295ab0b485b8bc50d2264bcae2acd06f25caaf upstream.
After Commit 3499ba8198cad ("xen: Fix event channel callback via INTX/GSI"), xenbus_probe() will be called too early on Arm. This will recent to a guest hang during boot.
If the hang wasn't there, we would have ended up to call xenbus_probe() twice (the second time is in xenbus_probe_initcall()).
We don't need to initialize xenbus_probe() early for Arm guest. Therefore, the call in xen_guest_init() is now removed.
After this change, there is no more external caller for xenbus_probe(). So the function is turned to a static one. Interestingly there were two prototypes for it.
Cc: stable@vger.kernel.org Fixes: 3499ba8198cad ("xen: Fix event channel callback via INTX/GSI") Reported-by: Ian Jackson iwj@xenproject.org Signed-off-by: Julien Grall jgrall@amazon.com Reviewed-by: David Woodhouse dwmw@amazon.co.uk Reviewed-by: Stefano Stabellini sstabellini@kernel.org Link: https://lore.kernel.org/r/20210210170654.5377-1-julien@xen.org Signed-off-by: Juergen Gross jgross@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm/xen/enlighten.c | 2 -- drivers/xen/xenbus/xenbus.h | 1 - drivers/xen/xenbus/xenbus_probe.c | 2 +- include/xen/xenbus.h | 2 -- 4 files changed, 1 insertion(+), 6 deletions(-)
--- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -404,8 +404,6 @@ static int __init xen_guest_init(void) return -ENOMEM; } gnttab_init(); - if (!xen_initial_domain()) - xenbus_probe();
/* * Making sure board specific code will not set up ops for --- a/drivers/xen/xenbus/xenbus.h +++ b/drivers/xen/xenbus/xenbus.h @@ -115,7 +115,6 @@ int xenbus_probe_node(struct xen_bus_typ const char *type, const char *nodename); int xenbus_probe_devices(struct xen_bus_type *bus); -void xenbus_probe(void);
void xenbus_dev_changed(const char *node, struct xen_bus_type *bus);
--- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -683,7 +683,7 @@ void unregister_xenstore_notifier(struct } EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
-void xenbus_probe(void) +static void xenbus_probe(void) { xenstored_ready = 1;
--- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -187,8 +187,6 @@ void xs_suspend_cancel(void);
struct work_struct;
-void xenbus_probe(void); - #define XENBUS_IS_ERR_READ(str) ({ \ if (!IS_ERR(str) && strlen(str) == 0) { \ kfree(str); \