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=-2.5 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 450F2C282DD for ; Thu, 23 May 2019 15:00:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2368D20881 for ; Thu, 23 May 2019 15:00:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730956AbfEWPAA (ORCPT ); Thu, 23 May 2019 11:00:00 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57502 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730796AbfEWO77 (ORCPT ); Thu, 23 May 2019 10:59:59 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D5BD88110C; Thu, 23 May 2019 14:59:53 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.159]) by smtp.corp.redhat.com (Postfix) with SMTP id 84FC0438A; Thu, 23 May 2019 14:59:48 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 23 May 2019 16:59:51 +0200 (CEST) Date: Thu, 23 May 2019 16:59:45 +0200 From: Oleg Nesterov To: David Laight Cc: 'Deepa Dinamani' , Linux Kernel Mailing List , Andrew Morton , Alexander Viro , Arnd Bergmann , "dbueso@suse.de" , "axboe@kernel.dk" , Davidlohr Bueso , Eric Wong , Jason Baron , Linux FS-devel Mailing List , linux-aio , Omar Kilani , Thomas Gleixner , "stable@vger.kernel.org" Subject: Re: [PATCH v2] signal: Adjust error codes according to restore_user_sigmask() Message-ID: <20190523145944.GB23070@redhat.com> References: <20190522032144.10995-1-deepa.kernel@gmail.com> <20190522150505.GA4915@redhat.com> <20190522161407.GB4915@redhat.com> <4f7b6dbeab1d424baaebd7a5df116349@AcuMS.aculab.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4f7b6dbeab1d424baaebd7a5df116349@AcuMS.aculab.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 23 May 2019 14:59:59 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 05/23, David Laight wrote: > > I'm confused... Me too. To clarify, the current code is obviously buggy, pselect/whatever shouldn't return 0 (or anything else) if it was interrupted and we are going to deliver the signal. But it seems that Deepa has other concerns which I do not understand at all. In any case, the signal_pending() check _inside_ restore_user_sigmask() can't be right, with or without this patch. If nothing else, a signal can come right after the check. > So epoll() can return 'success' or 'timeout' (etc) and the handler for SIG_URG > should still be called. Not sure I understand... OK, suppose that you do block-all-signals; ret = pselect(..., sigmask(SIG_URG)); if it returns success/timeout then the handler for SIG_URG should not be called? or I am totally confused... Oleg.