Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751802AbcCFU1z (ORCPT ); Sun, 6 Mar 2016 15:27:55 -0500 Received: from port70.net ([81.7.13.123]:51978 "EHLO port70.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751360AbcCFU1k (ORCPT ); Sun, 6 Mar 2016 15:27:40 -0500 Date: Sun, 6 Mar 2016 21:27:38 +0100 From: Szabolcs Nagy To: Stas Sergeev Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Andy Lutomirski , Oleg Nesterov , Shuah Khan Subject: Re: [PATCH v4 0/2] make sigaltstack() compatible with swapcontext() Message-ID: <20160306202738.GU29662@port70.net> References: <1456781345-8243-1-git-send-email-stsp@list.ru> <20160306200207.GT29662@port70.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160306200207.GT29662@port70.net> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 637 Lines: 19 * Szabolcs Nagy [2016-03-06 21:02:08 +0100]: > * Stas Sergeev [2016-03-01 00:29:03 +0300]: > > The following patches make it possible to use swapcontext() > > in a sighandler that works on sigaltstack. > > i don't think that's possible, the (obsolete) userspace > *context functions cannot operate on kernel provided > ucontext_t structs, so they are not usable in signal > handlers. > > at least not on most target archs. > > so i don't understand how the tests can work portably. > i see the test does not use the kernel ucontext_t and only synchronous context switch is done sorry for the noise.