From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 949FBC43334 for ; Wed, 5 Sep 2018 14:34:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D7F02075C for ; Wed, 5 Sep 2018 14:34:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2D7F02075C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727729AbeIETFE (ORCPT ); Wed, 5 Sep 2018 15:05:04 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:59160 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726528AbeIETFE (ORCPT ); Wed, 5 Sep 2018 15:05:04 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9875280D; Wed, 5 Sep 2018 07:34:36 -0700 (PDT) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 67A343F575; Wed, 5 Sep 2018 07:34:36 -0700 (PDT) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id CB7A51AE3546; Wed, 5 Sep 2018 15:34:50 +0100 (BST) From: Will Deacon To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, arnd@arndb.de, linux@dominikbrodowski.net, ebiederm@xmission.com, akpm@linux-foundation.org, viro@zeniv.linux.org.uk, oleg@redhat.com, steve.mcintyre@arm.com, dave.martin@arm.com, Will Deacon Subject: [RESEND PATCH 0/2] Don't use SIGMINSTKSZ when enforcing alternative signal stack size for compat tasks Date: Wed, 5 Sep 2018 15:34:41 +0100 Message-Id: <1536158083-30166-1-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, This is a resend of: http://lists.infradead.org/pipermail/linux-arm-kernel/2018-July/593559.html now based on 4.19-rc2. The Debian folks have observed a failure in the 32-bit arm glibc testsuite when running under a 64-bit kernel. They tracked this down to sigaltstack(2) enforcing the alternative signal stack to be at least SIGMINSTKSZ bytes, which is higher for native arm64 tasks than compat 32-bit tasks. These patches resolve the issue by allowing an architecture to define COMPAT_SIGMINSTKSZ for compat tasks, which is then used by the sigaltstack checking code. Feedback welcome, Will --->8 Will Deacon (2): signal: Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstack arm64: compat: Provide definition for COMPAT_SIGMINSTKSZ arch/arm64/include/asm/compat.h | 1 + include/linux/compat.h | 3 +++ kernel/signal.c | 14 +++++++++----- 3 files changed, 13 insertions(+), 5 deletions(-) -- 2.1.4