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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 87924C31E46 for ; Wed, 12 Jun 2019 08:39:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 640F0206E0 for ; Wed, 12 Jun 2019 08:39:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731543AbfFLIj5 convert rfc822-to-8bit (ORCPT ); Wed, 12 Jun 2019 04:39:57 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([146.101.78.151]:51816 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731299AbfFLIj5 (ORCPT ); Wed, 12 Jun 2019 04:39:57 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-77-sKXNtwkfNyeBMA4oS27QZg-1; Wed, 12 Jun 2019 09:39:54 +0100 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b::d117) by AcuMS.aculab.com (fd9f:af1c:a25b::d117) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 12 Jun 2019 09:39:53 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Wed, 12 Jun 2019 09:39:53 +0100 From: David Laight To: 'Oleg Nesterov' , "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 , "linux-arch@vger.kernel.org" Subject: RE: [RFC PATCH 1/5] signal: Teach sigsuspend to use set_user_sigmask Thread-Topic: [RFC PATCH 1/5] signal: Teach sigsuspend to use set_user_sigmask Thread-Index: AQHVIIdIknGdQ9+D0UeylJNmvFzQKKaXsr4w Date: Wed, 12 Jun 2019 08:39:53 +0000 Message-ID: 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> <20190610162244.GB8127@redhat.com> <87lfy96sta.fsf@xmission.com> <20190611185548.GA31214@redhat.com> In-Reply-To: <20190611185548.GA31214@redhat.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-MC-Unique: sKXNtwkfNyeBMA4oS27QZg-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Oleg Nesterov [mailto:oleg@redhat.com] > Sent: 11 June 2019 19:56 > On 06/10, Eric W. Biederman wrote: > > > > Personally I don't think anyone sane would intentionally depend on this > > and I don't think there is a sufficiently reliable way to depend on this > > by accident that people would actually be depending on it. > > Agreed. > > As I said I like these changes and I see nothing wrong. To me they fix the > current behaviour, or at least make it more consistent. > > But perhaps this should be documented in the changelog? To make it clear > that this change was intentional. What happens if you run the test program I posted yesterday after the changes? It looks like pselect() and epoll_pwait() operated completely differently. pselect() would always calls the signal handlers. epoll_pwait() only calls them when EINTR is returned. So changing epoll_pwait() and pselect() to work the same way is bound to break some applications. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)