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=-7.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_PASS,USER_AGENT_MUTT 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 28121C4360F for ; Thu, 7 Mar 2019 14:11:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EBCFC20684 for ; Thu, 7 Mar 2019 14:11:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="BIt+RkQP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726233AbfCGOLs (ORCPT ); Thu, 7 Mar 2019 09:11:48 -0500 Received: from mail-pg1-f195.google.com ([209.85.215.195]:32968 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726120AbfCGOLs (ORCPT ); Thu, 7 Mar 2019 09:11:48 -0500 Received: by mail-pg1-f195.google.com with SMTP id h11so11364190pgl.0 for ; Thu, 07 Mar 2019 06:11:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=9LeTIkdxMwZvglFvizWchN+b3CkwK+5wg9lYTOOyRLw=; b=BIt+RkQP7xn4VMu5EZCLcF4/fAcyOjxDJ/caPi6v0qVmX3X7V867du25cUTqhfXAPQ Uz3cXlWyGrl7B0616/obZ5oxFNHM1XmRNMTbS4k9ThhHepyV/gJbRvuWHCUB+dSTGcnH iYiOkT+GM8DbJlevNF2UUvC9US5Fzw78hxXzHUfZk3nDZyD9QT/PlGeWMwy7rsx/SizT johES3WqgNLfs1RQ2cbzlqe/0s9w3pCuwLS0/4j+Hg6kCXtFsHiinQy/oIJlIenPQxU9 RvEvQpokwfVBN0FKDmxBSSW9dWarSOWrkJIKzAD02a+jeGQTTQOQ/ZPg2BiXBJ1dFWhI H3eQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=9LeTIkdxMwZvglFvizWchN+b3CkwK+5wg9lYTOOyRLw=; b=iQ57tK/JyeuYqi8Qn5NMT73l2b9mEgk0eI8BgUiz6sATF0cQTX6zbQ1JkjHFtLUz28 3AQAimY6ya6s9nvgy2SUMu8rHQsBSCx15ntBaZwG2Cq9h5WAmCAsWxJKTFZfGrlQL6tL EpnS1je6OmAKDASQFhvQYBR8qpy6sI3lOcMwP2BVBYJOB5ZVB2zhWcfARHf1ueyKbesu IRwToAA0FN6kcLGLTXb25RY+YSW19gLRFdghZ7pZGrUW30EO1gyHXlj+MZzY3QdnQZgl scfPX2MXYWj4sM73RsaUojGrewaPP9J0XULcxuk4nAHCbN/Ky6wg4G8wNKxJK41lOrMg UBxg== X-Gm-Message-State: APjAAAWoK4BA550ydjUf7vH6IiSid8PU5xNU1A9IC7PRu7ehhHhDFr7l fOLYfP0bcTaG+VTwJAvB7tY= X-Google-Smtp-Source: APXvYqz5TcqtUPkAid/VyGs5g12QymmVgaWrtbhvtXvjtoF8haf/JDiLPIRDtWGga+IvXJw/q25SLg== X-Received: by 2002:a63:43:: with SMTP id 64mr11521398pga.64.1551967906120; Thu, 07 Mar 2019 06:11:46 -0800 (PST) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id a1sm7704690pfn.26.2019.03.07.06.11.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 07 Mar 2019 06:11:45 -0800 (PST) Date: Thu, 7 Mar 2019 06:11:43 -0800 From: Guenter Roeck To: Christophe Leroy Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v2 03/10] powerpc/6xx: Store PGDIR physical address in a SPRG Message-ID: <20190307141143.GA26761@roeck-us.net> References: <297f30d8ba75cb0e9ebe0a776d96c19750105570.1550745320.git.christophe.leroy@c-s.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <297f30d8ba75cb0e9ebe0a776d96c19750105570.1550745320.git.christophe.leroy@c-s.fr> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Thu, Feb 21, 2019 at 10:37:55AM +0000, Christophe Leroy wrote: > Use SPRN_SPRG2 to store the current thread PGDIR and > avoid reading thread_struct.pgdir at every TLB miss. > This patch causes a number of silent (no crash) qemu boot stalls in -next. See https://kerneltests.org/builders/qemu-ppc-next/builds/1080/steps/qemubuildcommand/logs/stdio for an example. Unfortunately, it is not possible to revert the patch due to subsequent patches, so I was unable to test a revert. Bisect log is attached. Guenter --- # bad: [cf08baa29613dd899954089e7cc7dba1d478b365] Add linux-next specific files for 20190306 # good: [1c163f4c7b3f621efff9b28a47abb36f7378d783] Linux 5.0 git bisect start 'HEAD' 'v5.0' # bad: [6cc8f3499ec8d31904ab9083980a91736512cb37] Merge remote-tracking branch 'vfs/for-next' git bisect bad 6cc8f3499ec8d31904ab9083980a91736512cb37 # good: [63bdf4284c38a48af21745ceb148a087b190cd21] Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 git bisect good 63bdf4284c38a48af21745ceb148a087b190cd21 # good: [520b5fc601ab760fee7ea0c403b42d04e8ebfd93] Merge remote-tracking branch 'arm-soc/for-next' git bisect good 520b5fc601ab760fee7ea0c403b42d04e8ebfd93 # bad: [d7f54e4e0d4e90f5df78da8d6a830bafad3b535a] Merge remote-tracking branch 'xtensa/xtensa-for-next' git bisect bad d7f54e4e0d4e90f5df78da8d6a830bafad3b535a # good: [0c1a78523542fb3d2e6c5ac7955c8ca8f6482e6f] Merge remote-tracking branch 'clk/clk-next' git bisect good 0c1a78523542fb3d2e6c5ac7955c8ca8f6482e6f # bad: [fb0b0a73b223fc113e961b1d921322844e9c30d9] powerpc: Enable kcov git bisect bad fb0b0a73b223fc113e961b1d921322844e9c30d9 # good: [d0055df0c9c1471c389197a69f43e300185a75aa] Merge branch 'topic/dma' into next git bisect good d0055df0c9c1471c389197a69f43e300185a75aa # good: [0df977eafc792a5365a7f81d8d5920132e03afad] powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS git bisect good 0df977eafc792a5365a7f81d8d5920132e03afad # bad: [665bed2386e5dc29844ad78c7ef1464664b103ec] powerpc/8xx: replace most #ifdef by IS_ENABLED() in 8xx_mmu.c git bisect bad 665bed2386e5dc29844ad78c7ef1464664b103ec # bad: [78ca1108b10927b3d068c8da91352b0f4cd01fc5] powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling git bisect bad 78ca1108b10927b3d068c8da91352b0f4cd01fc5 # bad: [a8a121995b2e4f227fddc534c6bd5f1c02cbe2ee] powerpc/603: Don't handle kernel page TLB misses when not need git bisect bad a8a121995b2e4f227fddc534c6bd5f1c02cbe2ee # bad: [2c12393f577396a51b7e0537bd3eb29dcc26dc1b] powerpc/603: use physical address directly in TLB miss handlers. git bisect bad 2c12393f577396a51b7e0537bd3eb29dcc26dc1b # bad: [93c4a162b014d238a287f8264adb25c009c79e61] powerpc/6xx: Store PGDIR physical address in a SPRG git bisect bad 93c4a162b014d238a287f8264adb25c009c79e61 # first bad commit: [93c4a162b014d238a287f8264adb25c009c79e61] powerpc/6xx: Store PGDIR physical address in a SPRG