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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 76E7BC4740A for ; Tue, 10 Sep 2019 14:20:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46BB421881 for ; Tue, 10 Sep 2019 14:20:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kraav.com header.i=@kraav.com header.b="CJKPC/f4"; dkim=pass (1024-bit key) header.d=kraav.com header.i=@kraav.com header.b="ZqG4nvbg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732122AbfIJOUz (ORCPT ); Tue, 10 Sep 2019 10:20:55 -0400 Received: from mail-out.elkdata.ee ([185.7.252.64]:63251 "EHLO mail-out.elkdata.ee" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726060AbfIJOUy (ORCPT ); Tue, 10 Sep 2019 10:20:54 -0400 Received: from mail-relay2.elkdata.ee (unknown [185.7.252.69]) by mail-out.elkdata.ee (Postfix) with ESMTP id 023F337295B for ; Tue, 10 Sep 2019 17:20:51 +0300 (EEST) Received: from mail-relay2.elkdata.ee (unknown [185.7.252.69]) by mail-relay2.elkdata.ee (Postfix) with ESMTP id 00CA58308C9 for ; Tue, 10 Sep 2019 17:20:51 +0300 (EEST) X-Virus-Scanned: amavisd-new at elkdata.ee Received: from mail-relay2.elkdata.ee ([185.7.252.69]) by mail-relay2.elkdata.ee (mail-relay2.elkdata.ee [185.7.252.69]) (amavisd-new, port 10024) with ESMTP id bXGeo76rMJmW for ; Tue, 10 Sep 2019 17:20:48 +0300 (EEST) Received: from mail.elkdata.ee (unknown [185.7.252.68]) by mail-relay2.elkdata.ee (Postfix) with ESMTP id 324F98308AA for ; Tue, 10 Sep 2019 17:20:48 +0300 (EEST) Received: from mail.meie.biz (21-182-190-90.sta.estpak.ee [90.190.182.21]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: leho@jaanalind.ee) by mail.elkdata.ee (Postfix) with ESMTPSA id 29A2A60BF2D for ; Tue, 10 Sep 2019 17:20:48 +0300 (EEST) Received: by mail.meie.biz (Postfix, from userid 500) id 1F3E1A9568B; Tue, 10 Sep 2019 17:20:48 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kraav.com; s=mail; t=1568125248; bh=cKzJGcLcvGFlhWR96PpkKHDXEqAYhIVzH0O2bLoUI5M=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=CJKPC/f4i5w/89FBdAFSaf/wh1f9EDZNuZbAZDpG/QceOYuay0VtRrxRnJa7dFMcW dZVoFcFvoUaPrCDAlolRfNdXjzNsmfwStk5IMvakRhg1ARhb8Mln3RyDs0BP8WocWs K9nvh1NFt67ORIAyLDVl3QzgTvLE+ZLiAg/CNFps= Received: from papaya (papaya.meie.biz [192.168.1.206]) by mail.meie.biz (Postfix) with ESMTPA id A476DA95685; Tue, 10 Sep 2019 17:20:47 +0300 (EEST) Authentication-Results: mail.meie.biz; dmarc=fail (p=none dis=none) header.from=kraav.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kraav.com; s=mail; t=1568125247; bh=cKzJGcLcvGFlhWR96PpkKHDXEqAYhIVzH0O2bLoUI5M=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=ZqG4nvbgwQIPLlLUrxr8JwKybOsxS6R1lSq8I/RFqfuiBLssgCH2d5Zt+FtSzeNV2 5qJ/q1CnGiEvaiRIjEoOZQC872RhMa7hj+G62JjO8hxvXGfoabJ5ZOS57Phd5CDYAd 2LgEQPOGtuIaVpy3tm674rVQP/7HxJ+aYWHk/0KQ= Received: (nullmailer pid 3786 invoked by uid 1000); Tue, 10 Sep 2019 14:20:47 -0000 Date: Tue, 10 Sep 2019 17:20:47 +0300 From: Leho Kraav To: Chris Wilson Cc: "intel-gfx@lists.freedesktop.org" , Martin Wilck , "linux-kernel@vger.kernel.org" Subject: Re: 5.3-rc3: Frozen graphics with kcompactd migrating i915 pages Message-ID: <20190910142047.GB3029@papaya> References: <156535522344.29541.9312856809559678262@skylake-alporthouse-com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <156535522344.29541.9312856809559678262@skylake-alporthouse-com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Bogosity: Unsure, tests=bogofilter, spamicity=0.500000, version=1.2.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 09, 2019 at 01:53:43PM +0100, Chris Wilson wrote: > Quoting Martin Wilck (2019-08-09 13:41:42) > > This happened to me today, running kernel 5.3.0-rc3-1.g571863b-default > > (5.3-rc3 with just a few patches on top), after starting a KVM virtual > > machine. The X screen was frozen. Remote login via ssh was still > > possible, thus I was able to retrieve basic logs. > > > > sysrq-w showed two blocked processes (kcompactd0 and KVM). After a > > minute, the same two processes were still blocked. KVM seems to try to > > acquire a lock that kcompactd is holding. kcompactd is waiting for IO > > to complete on pages owned by the i915 driver. > > My bad, it's known. We haven't decided on whether to revert the > unfortunate recursive locking (and so hit another warn elsewhere) or to > ignore the dirty pages (and so risk losing data across swap). > > cb6d7c7dc7ff ("drm/i915/userptr: Acquire the page lock around set_page_dirty()") > -Chris Hi Chris. Is this exactly what I'm hitting at https://bugs.freedesktop.org/show_bug.cgi?id=111500 perhaps? It reliably breaks the graphics userland, as the machine consistently freezes at any random moment. Any workaround options, even if with a performance penalty? Revert cb6d7c7dc7ff but side effects? 5.3 has useful NVMe power mgmt updates for laptops, I'd like to stick with the newest if possible. -- Leho Kraav, senior technology & digital marketing architect