[PATCH] tty: hvc: fix return value of __setup handler

[Randy Dunlap]

__setup() handlers should return 1 to indicate that the boot option
has been handled or 0 to indicate that it was not handled.
Add a pr_warn() message if the option value is invalid and then
always return 1.

Fixes: 86b40567b917 ("tty: replace strict_strtoul() with kstrtoul()")
Signed-off-by: Randy Dunlap <rdunlap at infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov at omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3 at omprussia.ru
Cc: Jingoo Han <jg1.han at samsung.com>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Cc: Jiri Slaby <jirislaby at kernel.org>
Cc: Michael Ellerman <mpe at ellerman.id.au>
Cc: Julian Wiedmann <jwi at linux.ibm.com>
Cc: Vasily Gorbik <gor at linux.ibm.com>
Cc: linuxppc-dev at lists.ozlabs.org
---
 drivers/tty/hvc/hvc_iucv.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- linux-next-20220307.orig/drivers/tty/hvc/hvc_iucv.c
+++ linux-next-20220307/drivers/tty/hvc/hvc_iucv.c
@@ -1417,7 +1417,9 @@ out_error:
  */
 static	int __init hvc_iucv_config(char *val)
 {
-	 return kstrtoul(val, 10, &hvc_iucv_devices);
+	if (kstrtoul(val, 10, &hvc_iucv_devices))
+		pr_warn("hvc_iucv= invalid parameter value '%s'\n", val);
+	return 1;
 }