[PATCH 2/3] pc-bios/s390-ccw: break loop if a null block number is reached

[Marc Hartmayer]

Break the loop if `cur_block_nr` is a null block number because this
means that the end of chunk is reached. In this case we will try to
boot the default entry.

Fixes: ba831b25262a ("s390-ccw: read stage2 boot loader data to find menu")
Reviewed-by: Collin Walling <wall...@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhart...@linux.ibm.com>
---
 pc-bios/s390-ccw/bootmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index 0d29dceaa3cc..08f16c5595a3 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -192,7 +192,7 @@ static int eckd_get_boot_menu_index(block_number_t 
s1b_block_nr)
     for (i = 0; i < STAGE2_BLK_CNT_MAX; i++) {
         cur_block_nr = eckd_block_num(&s1b->seek[i].chs);
 
-        if (!cur_block_nr) {
+        if (!cur_block_nr || is_null_block_number(cur_block_nr)) {
             break;
         }
 
-- 
2.25.4