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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,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 5A0CCC43381 for ; Thu, 7 Mar 2019 18:14:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2444120675 for ; Thu, 7 Mar 2019 18:14:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=c-s.fr header.i=@c-s.fr header.b="BDRkZ6hf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726542AbfCGSOz (ORCPT ); Thu, 7 Mar 2019 13:14:55 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:65434 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726180AbfCGSOy (ORCPT ); Thu, 7 Mar 2019 13:14:54 -0500 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 44Ff156TcVz9v0JP; Thu, 7 Mar 2019 19:14:49 +0100 (CET) Authentication-Results: localhost; dkim=pass reason="1024-bit key; insecure key" header.d=c-s.fr header.i=@c-s.fr header.b=BDRkZ6hf; dkim-adsp=pass; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id wTdFRGYppYtS; Thu, 7 Mar 2019 19:14:49 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 44Ff155FRFz9v0JM; Thu, 7 Mar 2019 19:14:49 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c-s.fr; s=mail; t=1551982489; bh=Q5wddiC7ZY4cQ0vEFxppoDBXvYS1NYMd0ly3QzUTL5E=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=BDRkZ6hfbteBarh7wE9TOm3KiKZygNkuDlTfdnV3bYPqyivONnDSf0qpoqHcq495c PkmHTkmB2j4Qk2MfAGc+O7Rqi+EVj2Q2caqDEp5lcpqu9sSUb9b8Ct9iBXZmJWZhVf S55hNuYnaLKELl/Zzi/CABPXXCnSn83QwmHAobQk= Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 36D7C8BF27; Thu, 7 Mar 2019 19:14:51 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id zVlMaDxUV_Cz; Thu, 7 Mar 2019 19:14:51 +0100 (CET) Received: from localhost.localdomain (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id B0D138BEE3; Thu, 7 Mar 2019 19:14:50 +0100 (CET) Subject: Re: [PATCH v2 03/10] powerpc/6xx: Store PGDIR physical address in a SPRG To: Guenter Roeck Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org References: <297f30d8ba75cb0e9ebe0a776d96c19750105570.1550745320.git.christophe.leroy@c-s.fr> <20190307141143.GA26761@roeck-us.net> From: Christophe Leroy Message-ID: <2acc1691-0f74-8843-ecdd-64ba8705de20@c-s.fr> Date: Thu, 7 Mar 2019 18:14:09 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20190307141143.GA26761@roeck-us.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 03/07/2019 02:11 PM, Guenter Roeck wrote: > 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. Oops. Could you try the fix below ? diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S b/arch/powerpc/kernel/cpu_setup_6xx.S index 6f1c11e0691f..7534ecff5e92 100644 --- a/arch/powerpc/kernel/cpu_setup_6xx.S +++ b/arch/powerpc/kernel/cpu_setup_6xx.S @@ -24,9 +24,6 @@ BEGIN_MMU_FTR_SECTION li r10,0 mtspr SPRN_SPRG_603_LRU,r10 /* init SW LRU tracking */ END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU) - lis r10, (swapper_pg_dir - PAGE_OFFSET)@h - ori r10, r10, (swapper_pg_dir - PAGE_OFFSET)@l - mtspr SPRN_SPRG_PGDIR, r10 BEGIN_FTR_SECTION bl __init_fpu_registers diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S index ce6a972f2584..48051c8977c5 100644 --- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S @@ -855,6 +855,9 @@ __secondary_start: li r3,0 stw r3, RTAS_SP(r4) /* 0 => not in RTAS */ #endif + lis r4, (swapper_pg_dir - PAGE_OFFSET)@h + ori r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l + mtspr SPRN_SPRG_PGDIR, r4 /* enable MMU and jump to start_secondary */ li r4,MSR_KERNEL @@ -942,6 +945,9 @@ start_here: li r3,0 stw r3, RTAS_SP(r4) /* 0 => not in RTAS */ #endif + lis r4, (swapper_pg_dir - PAGE_OFFSET)@h + ori r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l + mtspr SPRN_SPRG_PGDIR, r4 /* stack */ lis r1,init_thread_union@ha diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S index 1f13494efb2b..587e4550d83e 100644 --- a/arch/powerpc/mm/hash_low_32.S +++ b/arch/powerpc/mm/hash_low_32.S @@ -70,12 +70,12 @@ _GLOBAL(hash_page) lis r0,KERNELBASE@h /* check if kernel address */ cmplw 0,r4,r0 ori r3,r3,_PAGE_USER|_PAGE_PRESENT /* test low addresses as user */ - mfspr r5, SPRN_SPRG_PGDIR /* virt page-table root */ + mfspr r5, SPRN_SPRG_PGDIR /* phys page-table root */ blt+ 112f /* assume user more likely */ - lis r5,swapper_pg_dir@ha /* if kernel address, use */ - addi r5,r5,swapper_pg_dir@l /* kernel page table */ + lis r5, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ + addi r5 ,r5 , (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */ rlwimi r3,r9,32-12,29,29 /* MSR_PR -> _PAGE_USER */ -112: tophys(r5, r5) +112: #ifndef CONFIG_PTE_64BIT rlwimi r5,r4,12,20,29 /* insert top 10 bits of address */ lwz r8,0(r5) /* get pmd entry */ Thanks Christophe > > 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 >