s390/vmcp: correct early_param handling

Check "p" is not NULL before passing it to memparse, which doesn't
handle that case explicitly.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/s390/char/vmcp.c b/drivers/s390/char/vmcp.c
index 0fa1b6b1491a..9e066281e2d0 100644
--- a/drivers/s390/char/vmcp.c
+++ b/drivers/s390/char/vmcp.c
@@ -43,6 +43,8 @@ static struct cma *vmcp_cma;
 
 static int __init early_parse_vmcp_cma(char *p)
 {
+        if (!p)
+                return 1;
         vmcp_cma_size = ALIGN(memparse(p, NULL), PAGE_SIZE);
         return 0;
 }