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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CDED4C77B7A for ; Thu, 18 May 2023 18:24:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229848AbjERSYO (ORCPT ); Thu, 18 May 2023 14:24:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229449AbjERSYN (ORCPT ); Thu, 18 May 2023 14:24:13 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C686189 for ; Thu, 18 May 2023 11:23:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684434204; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=RJi9ZlLdcLDeLRUcrDXyTC7zgfOSpkMfpLKIfWFhcvU=; b=NepfBqdVRNCffsLGEEH394sX4uGfAi8+RIOvm8cThpNWyXbdQDHpL8mQybTklU9xsKbyPz mV+cA9O4NB/etcLfPhKeTvZvYCDTD/MphL1zAR0sL6lGril/EhBoYcGu+nV54LZtXMQIe5 7RcB28LDQ3yp8MdAb5ImY1spWyASiN8= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-208-xNxDOZS-O3yjF8lhA3tZ7g-1; Thu, 18 May 2023 14:23:20 -0400 X-MC-Unique: xNxDOZS-O3yjF8lhA3tZ7g-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 294E029AB448; Thu, 18 May 2023 18:23:20 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.20]) by smtp.corp.redhat.com (Postfix) with SMTP id 2CF7EC15BA0; Thu, 18 May 2023 18:23:16 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 18 May 2023 20:23:05 +0200 (CEST) Date: Thu, 18 May 2023 20:23:02 +0200 From: Oleg Nesterov To: Christian Brauner Cc: Mike Christie , linux@leemhuis.info, nicolas.dichtel@6wind.com, axboe@kernel.dk, ebiederm@xmission.com, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, mst@redhat.com, sgarzare@redhat.com, jasowang@redhat.com, stefanha@redhat.com Subject: Re: [RFC PATCH 1/8] signal: Dequeue SIGKILL even if SIGNAL_GROUP_EXIT/group_exec_task is set Message-ID: <20230518182301.GB5817@redhat.com> References: <20230518000920.191583-1-michael.christie@oracle.com> <20230518000920.191583-2-michael.christie@oracle.com> <20230518-kontakt-geduckt-25bab595f503@brauner> <7412912a-a470-bd3d-fb1c-54c094cc01ee@oracle.com> <20230518-ratgeber-erbeben-843e68b0d6ac@brauner> <20230518180809.GA5817@redhat.com> <20230518-fettgehalt-erdbeben-25587a432815@brauner> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230518-fettgehalt-erdbeben-25587a432815@brauner> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/18, Christian Brauner wrote: > > On Thu, May 18, 2023 at 08:08:10PM +0200, Oleg Nesterov wrote: > > On 05/18, Christian Brauner wrote: > > > > > > Yeah, but these are issues that exist with PF_IO_WORKER then too > > > > This was my thought too but I am starting to think I was wrong. > > > > Of course I don't understand the code in io_uring/ but it seems > > that it always breaks the IO loops if get_signal() returns SIGKILL. > > Yeah, it does and I think Mike has a point that vhost could be running > into an issue here that io_uring currently does avoid. But I don't think > we should rely on that. So what do you propose? Unless (quite possibly) I am confused again, unlike io_uring vhost can't tolerate signal_pending() == T in the cleanup-after-SIGKILL paths? Oleg.