s390/protvirt: support ultravisor without secure storage limit

Avoid potential crash due to lack of secure storage limit. Check that
max_sec_stor_addr is not 0 before adjusting vmalloc position.

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

diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
index 4233245..1a166a1 100644 (file)
--- a/arch/s390/kernel/uv.c
+++ b/arch/s390/kernel/uv.c
@@ -90,7 +90,8 @@ fail:
 
 void adjust_to_uv_max(unsigned long *vmax)
 {
-       *vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr);
+       if (uv_info.max_sec_stor_addr)
+               *vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr);
 }
 
 /*