diff options
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 5 | ||||
| -rw-r--r-- | drivers/tty/hvc/hvc_xen.c | 29 |
2 files changed, 29 insertions, 5 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a8d0afde7f85..68ab6fa72b68 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -8414,6 +8414,11 @@ Kernel parameters save/restore/migration must be enabled to handle larger domains. + xen_console_io [XEN,EARLY] + Boolean option to enable/disable the usage of the Xen + console_io hypercalls to read and write to the console. + Mostly useful for debugging and development. + xen_emul_unplug= [HW,X86,XEN,EARLY] Unplug Xen emulated devices Format: [unplug0,][unplug1] diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index 388a71afd6ef..95ec01b1aacf 100644 --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -51,6 +51,22 @@ static DEFINE_SPINLOCK(xencons_lock); /* ------------------------------------------------------------------ */ +static bool xen_console_io = false; +static int __initdata opt_console_io = -1; + +static int __init parse_xen_console_io(char *arg) +{ + bool val; + int ret; + + ret = kstrtobool(arg, &val); + if (ret == 0) + opt_console_io = (int)val; + + return ret; +} +early_param("xen_console_io", parse_xen_console_io); + static struct xencons_info *vtermno_to_xencons(int vtermno) { struct xencons_info *entry, *ret = NULL; @@ -331,7 +347,7 @@ static int xen_initial_domain_console_init(void) struct xencons_info *info; unsigned long flags; - if (!xen_initial_domain()) + if (!xen_console_io) return -ENODEV; info = vtermno_to_xencons(HVC_COOKIE); @@ -369,7 +385,7 @@ void xen_console_resume(void) { struct xencons_info *info = vtermno_to_xencons(HVC_COOKIE); if (info != NULL && info->irq) { - if (!xen_initial_domain()) + if (!xen_console_io) xen_console_update_evtchn(info); rebind_evtchn_irq(info->evtchn, info->irq); } @@ -601,7 +617,7 @@ static int __init xen_hvc_init(void) if (!xen_domain()) return -ENODEV; - if (xen_initial_domain()) { + if (xen_console_io) { ops = &dom0_hvc_ops; r = xen_initial_domain_console_init(); if (r < 0) @@ -647,14 +663,17 @@ static int __init xen_hvc_init(void) } device_initcall(xen_hvc_init); -static int xen_cons_init(void) +static int __init xen_cons_init(void) { const struct hv_ops *ops; + xen_console_io = opt_console_io >= 0 ? opt_console_io : + xen_initial_domain(); + if (!xen_domain()) return 0; - if (xen_initial_domain()) + if (xen_console_io) ops = &dom0_hvc_ops; else { int r; |