From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:56452 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965783AbeEXJpQ (ORCPT ); Thu, 24 May 2018 05:45:16 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hendrik Brueckner , Martin Schwidefsky Subject: [PATCH 4.4 61/92] s390: remove indirect branch from do_softirq_own_stack Date: Thu, 24 May 2018 11:38:38 +0200 Message-Id: <20180524093205.137407442@linuxfoundation.org> In-Reply-To: <20180524093159.286472249@linuxfoundation.org> References: <20180524093159.286472249@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martin Schwidefsky commit 9f18fff63cfd6f559daa1eaae60640372c65f84b upstream. 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 Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman --- arch/s390/kernel/irq.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/arch/s390/kernel/irq.c +++ b/arch/s390/kernel/irq.c @@ -173,10 +173,9 @@ 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 {