s390/head: avoid doubling early boot stack size under KASAN
Early boot stack uses predefined 4 pages of memory 0x8000-0xC000. This
stack is used to run not instumented decompressor/facilities
verification C code. It doesn't make sense to double its size when
the kernel is built with KASAN support. BOOT_STACK_ORDER is introduced
to avoid that.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S
index e209cfe..ce2cbbc 100644
--- a/arch/s390/boot/head.S
+++ b/arch/s390/boot/head.S
@@ -315,7 +315,7 @@
brasl %r14,startup_kernel
.Lstack:
- .long 0x8000 + THREAD_SIZE - STACK_FRAME_OVERHEAD
+ .long 0x8000 + (1<<(PAGE_SHIFT+BOOT_STACK_ORDER)) - STACK_FRAME_OVERHEAD
.align 8
6: .long 0x7fffffff,0xffffffff
diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h
index 79b4060..27248f4 100644
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -18,6 +18,7 @@
#else
#define THREAD_SIZE_ORDER 2
#endif
+#define BOOT_STACK_ORDER 2
#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
#ifndef __ASSEMBLY__
