From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934814AbaFTIZw (ORCPT ); Fri, 20 Jun 2014 04:25:52 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:42523 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932937AbaFTIZt (ORCPT ); Fri, 20 Jun 2014 04:25:49 -0400 Date: Fri, 20 Jun 2014 09:25:20 +0100 From: Will Deacon To: Colin Cross Cc: "linux-arm-kernel@lists.infradead.org" , Catalin Marinas , "linux-kernel@vger.kernel.org" , Andrew Morton , "stable@vger.kernel.org" Subject: Re: [PATCH] ARM64: implement TASK_SIZE_OF Message-ID: <20140620082520.GC25104@arm.com> References: <1403122209-26352-1-git-send-email-ccross@android.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1403122209-26352-1-git-send-email-ccross@android.com> 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 Hi Colin, On Wed, Jun 18, 2014 at 09:10:09PM +0100, Colin Cross wrote: > include/linux/sched.h implements TASK_SIZE_OF as TASK_SIZE if it > is not set by the architecture headers. TASK_SIZE uses the > current task to determine the size of the virtual address space. > On a 64-bit kernel this will cause reading /proc/pid/pagemap of a > 64-bit process from a 32-bit process to return EOF when it reads > past 0xffffffff. > > Implement TASK_SIZE_OF exactly the same as TASK_SIZE with > test_tsk_thread_flag instead of test_thread_flag. Looks sane to me. Acked-by: Will Deacon I take it you're being bitten by this in real software, hence the CC stable tag? Will