[PATCH] s390: 31 bit memory size limit

Limit reported memory size to 2GB if running in 31 bit mode.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S
index 928ca65e8bb2..d12cff11b4bc 100644
--- a/arch/s390/kernel/head.S
+++ b/arch/s390/kernel/head.S
@@ -535,8 +535,13 @@ startup:basr  %r13,0                     # get base
         lhi   %r1,0
         icm   %r1,3,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
         jnz   .Lscnd
-        l     %r1,.Lscpincr2-PARMAREA+4(%r4) # otherwise use this one
+        lhi   %r1,0x800                 # otherwise report 2GB
 .Lscnd:
+        lhi   %r3,0x800                 # limit reported memory size to 2GB
+        cr    %r1,%r3
+        jl    .Lno2gb
+        lr    %r1,%r3
+.Lno2gb:
         xr    %r3,%r3                   # same logic
         ic    %r3,.Lscpa1-PARMAREA(%r4)
         chi   %r3,0x00