From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753922AbdIIXEJ (ORCPT ); Sat, 9 Sep 2017 19:04:09 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43076 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753889AbdIIXEF (ORCPT ); Sat, 9 Sep 2017 19:04:05 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Marc Zyngier" , "Christoffer Dall" Date: Sat, 09 Sep 2017 22:47:15 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 160/233] arm: KVM: Allow unaligned accesses at HYP In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.48-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier commit 33b5c38852b29736f3b472dd095c9a18ec22746f upstream. We currently have the HSCTLR.A bit set, trapping unaligned accesses at HYP, but we're not really prepared to deal with it. Since the rest of the kernel is pretty happy about that, let's follow its example and set HSCTLR.A to zero. Modern CPUs don't really care. Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Ben Hutchings --- arch/arm/kvm/init.S | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/arch/arm/kvm/init.S +++ b/arch/arm/kvm/init.S @@ -109,7 +109,6 @@ __do_hyp_init: @ - Write permission implies XN: disabled @ - Instruction cache: enabled @ - Data/Unified cache: enabled - @ - Memory alignment checks: enabled @ - MMU: enabled (this code must be run from an identity mapping) mrc p15, 4, r0, c1, c0, 0 @ HSCR ldr r2, =HSCTLR_MASK @@ -117,8 +116,8 @@ __do_hyp_init: mrc p15, 0, r1, c1, c0, 0 @ SCTLR ldr r2, =(HSCTLR_EE | HSCTLR_FI | HSCTLR_I | HSCTLR_C) and r1, r1, r2 - ARM( ldr r2, =(HSCTLR_M | HSCTLR_A) ) - THUMB( ldr r2, =(HSCTLR_M | HSCTLR_A | HSCTLR_TE) ) + ARM( ldr r2, =(HSCTLR_M) ) + THUMB( ldr r2, =(HSCTLR_M | HSCTLR_TE) ) orr r1, r1, r2 orr r0, r0, r1 isb