From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964978AbaE3SVH (ORCPT ); Fri, 30 May 2014 14:21:07 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:34612 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964826AbaE3SVE (ORCPT ); Fri, 30 May 2014 14:21:04 -0400 Date: Fri, 30 May 2014 19:20:37 +0100 From: Will Deacon To: Larry Bassel Cc: Catalin Marinas , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linaro-kernel@lists.linaro.org" , "khilman@linaro.org" Subject: Re: [PATCH v6 1/2] arm64: adjust el0_sync so that a function can be called Message-ID: <20140530182037.GH22895@arm.com> References: <1401399904-24471-1-git-send-email-larry.bassel@linaro.org> <1401399904-24471-2-git-send-email-larry.bassel@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1401399904-24471-2-git-send-email-larry.bassel@linaro.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 29, 2014 at 10:45:03PM +0100, Larry Bassel wrote: > To implement the context tracker properly on arm64, > a function call needs to be made after debugging and > interrupts are turned on, but before the lr is changed > to point to ret_to_user(). If the function call > is made after the lr is changed the function will not > return to the correct place. > > For similar reasons, defer the setting of x0 so that > it doesn't need to be saved around the function call > (save far_el1 in x26 temporarily instead). Acked-by: Will Deacon Thanks guys! Will