s390: remove indirect branch from do_softirq_own_stack

The inline assembly to call __do_softirq on the irq stack uses
an indirect branch. This can be replaced with a normal relative
branch.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5ed6 ("s390: introduce execute-trampolines for branches")
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2018-04-24 11:18:49 +02:00
parent 4253b0e062
commit 9f18fff63c

View File

@ -176,10 +176,9 @@ void do_softirq_own_stack(void)
new -= STACK_FRAME_OVERHEAD;
((struct stack_frame *) new)->back_chain = old;
asm volatile(" la 15,0(%0)\n"
" basr 14,%2\n"
" brasl 14,__do_softirq\n"
" la 15,0(%1)\n"
: : "a" (new), "a" (old),
"a" (__do_softirq)
: : "a" (new), "a" (old)
: "0", "1", "2", "3", "4", "5", "14",
"cc", "memory" );
} else {