From: Juergen Gross jgross@suse.com
[ Upstream commit 37a72b08a3e1eb28053214dd8211eb09c2fd3187 ]
When booting the xenbus driver will wait for PV devices to have connected to their backends before continuing. The timeout is different between essential and non-essential devices.
Non-essential devices are identified by their nodenames directly in the xenbus driver, which requires to update this list in case a new device type being non-essential is added (this was missed for several types in the past).
In order to avoid this problem, add a "not_essential" flag to struct xenbus_driver which can be set to "true" by the respective frontend.
Set this flag for the frontends currently regarded to be not essential (vkbs and vfb) and use it for testing in the xenbus driver.
Signed-off-by: Juergen Gross jgross@suse.com Link: https://lore.kernel.org/r/20211022064800.14978-2-jgross@suse.com Reviewed-by: Boris Ostrovsky boris.ostrovsky@oracle.com Signed-off-by: Boris Ostrovsky boris.ostrovsky@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/input/misc/xen-kbdfront.c | 1 + drivers/video/fbdev/xen-fbfront.c | 1 + drivers/xen/xenbus/xenbus_probe_frontend.c | 14 +++----------- include/xen/xenbus.h | 1 + 4 files changed, 6 insertions(+), 11 deletions(-)
diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c index 4ff5cd2a6d8de..3d17a0b3fe511 100644 --- a/drivers/input/misc/xen-kbdfront.c +++ b/drivers/input/misc/xen-kbdfront.c @@ -542,6 +542,7 @@ static struct xenbus_driver xenkbd_driver = { .remove = xenkbd_remove, .resume = xenkbd_resume, .otherend_changed = xenkbd_backend_changed, + .not_essential = true, };
static int __init xenkbd_init(void) diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c index 5ec51445bee88..6826f986da436 100644 --- a/drivers/video/fbdev/xen-fbfront.c +++ b/drivers/video/fbdev/xen-fbfront.c @@ -695,6 +695,7 @@ static struct xenbus_driver xenfb_driver = { .remove = xenfb_remove, .resume = xenfb_resume, .otherend_changed = xenfb_backend_changed, + .not_essential = true, };
static int __init xenfb_init(void) diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c index 480944606a3c9..07b010a68fcf9 100644 --- a/drivers/xen/xenbus/xenbus_probe_frontend.c +++ b/drivers/xen/xenbus/xenbus_probe_frontend.c @@ -211,19 +211,11 @@ static int is_device_connecting(struct device *dev, void *data, bool ignore_none if (drv && (dev->driver != drv)) return 0;
- if (ignore_nonessential) { - /* With older QEMU, for PVonHVM guests the guest config files - * could contain: vfb = [ 'vnc=1, vnclisten=0.0.0.0'] - * which is nonsensical as there is no PV FB (there can be - * a PVKB) running as HVM guest. */ + xendrv = to_xenbus_driver(dev->driver);
- if ((strncmp(xendev->nodename, "device/vkbd", 11) == 0)) - return 0; + if (ignore_nonessential && xendrv->not_essential) + return 0;
- if ((strncmp(xendev->nodename, "device/vfb", 10) == 0)) - return 0; - } - xendrv = to_xenbus_driver(dev->driver); return (xendev->state < XenbusStateConnected || (xendev->state == XenbusStateConnected && xendrv->is_ready && !xendrv->is_ready(xendev))); diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index b94074c827721..b13eb86395e05 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -112,6 +112,7 @@ struct xenbus_driver { const char *name; /* defaults to ids[0].devicetype */ const struct xenbus_device_id *ids; bool allow_rebind; /* avoid setting xenstore closed during remove */ + bool not_essential; /* is not mandatory for boot progress */ int (*probe)(struct xenbus_device *dev, const struct xenbus_device_id *id); void (*otherend_changed)(struct xenbus_device *dev,