s390/stack: set lowcore kernel stack pointer early

Make sure the lowcore kernel stack pointer reflects the kernel stack of the
current task as early as possible, instead of having a NULL pointer there.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/kernel/head64.S b/arch/s390/kernel/head64.S
index 82399b4..f67982f 100644 (file)
--- a/arch/s390/kernel/head64.S
+++ b/arch/s390/kernel/head64.S
@@ -25,6 +25,7 @@ ENTRY(startup_continue)
        larl    %r14,init_task
        stg     %r14,__LC_CURRENT
        larl    %r15,init_thread_union+STACK_INIT_OFFSET
+       stg     %r15,__LC_KERNEL_STACK
        brasl   %r14,sclp_early_adjust_va       # allow sclp_early_printk
        brasl   %r14,startup_init               # s390 specific early init
        brasl   %r14,start_kernel               # common init code