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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 A3BB3C31E40 for ; Mon, 10 Jun 2019 16:23:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8177420859 for ; Mon, 10 Jun 2019 16:23:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391173AbfFJQXK (ORCPT ); Mon, 10 Jun 2019 12:23:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38434 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389293AbfFJQXK (ORCPT ); Mon, 10 Jun 2019 12:23:10 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C117C31628ED; Mon, 10 Jun 2019 16:22:54 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.159]) by smtp.corp.redhat.com (Postfix) with SMTP id 34B64600C7; Mon, 10 Jun 2019 16:22:48 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 10 Jun 2019 18:22:52 +0200 (CEST) Date: Mon, 10 Jun 2019 18:22:45 +0200 From: Oleg Nesterov To: "Eric W. Biederman" Cc: Andrew Morton , Deepa Dinamani , linux-kernel@vger.kernel.org, arnd@arndb.de, dbueso@suse.de, axboe@kernel.dk, dave@stgolabs.net, e@80x24.org, jbaron@akamai.com, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, omar.kilani@gmail.com, tglx@linutronix.de, Al Viro , Linus Torvalds , David Laight , linux-arch@vger.kernel.org Subject: Re: [RFC PATCH 1/5] signal: Teach sigsuspend to use set_user_sigmask Message-ID: <20190610162244.GB8127@redhat.com> References: <20190522032144.10995-1-deepa.kernel@gmail.com> <20190529161157.GA27659@redhat.com> <20190604134117.GA29963@redhat.com> <20190606140814.GA13440@redhat.com> <87k1dxaxcl.fsf_-_@xmission.com> <87ef45axa4.fsf_-_@xmission.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87ef45axa4.fsf_-_@xmission.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Mon, 10 Jun 2019 16:23:10 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 06/07, Eric W. Biederman wrote: > > +static int set_sigmask(sigset_t *kmask) > +{ > + set_restore_sigmask(); > + current->saved_sigmask = current->blocked; > + set_current_blocked(kmask); > + > + return 0; > +} I was going to do the same change except my version returns void ;) So ACK. As for 2-5, sorry I can't read them today, will do tomorrow. But at first glance... yes, we can remove TIF_RESTORE_SIGMASK. As for "remove saved_sigmask" I have some concerns... At least this means a user-visible change iiuc. Say, pselect unblocks a fatal signal. Say, SIGINT without a handler. Suppose SIGINT comes after set_sigmask(). Before this change the process will be killed. After this change it will be killed or not. It won't be killed if do_select() finds an already ready fd without blocking, or it finds a ready fd right after SIGINT interrupts poll_schedule_timeout(). And _to me_ the new behaviour makes more sense. But when it comes to user-visible changes you can never know if it breaks something or not. Oleg.