s390: clarify compressed image code path

The way the decompressor is hooked into the start-up code is rather
subtle, with a mix of multiply-defined symbols and hardcoded address
literals. Add some comments at the junction points to clarify how it
works.

Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S
index 56e4d8234ef2..4431905f8cfa 100644
--- a/arch/s390/kernel/head.S
+++ b/arch/s390/kernel/head.S
@@ -309,7 +309,9 @@ ENTRY(startup_kdump)
         l       %r15,.Lstack-.LPG0(%r13)
         ahi     %r15,-STACK_FRAME_OVERHEAD
         brasl   %r14,verify_facilities
-        /* Continue with startup code in head64.S */
+# For uncompressed images, continue in
+# arch/s390/kernel/head64.S. For compressed images, continue in
+# arch/s390/boot/compressed/head.S.
         jg      startup_continue
 
 .Lstack: