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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 E378DC433DF for ; Wed, 12 Aug 2020 12:46:37 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id AB09A2065C for ; Wed, 12 Aug 2020 12:46:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB09A2065C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 587A78D0009; Wed, 12 Aug 2020 08:46:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 540028D0001; Wed, 12 Aug 2020 08:46:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 426C78D0009; Wed, 12 Aug 2020 08:46:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0231.hostedemail.com [216.40.44.231]) by kanga.kvack.org (Postfix) with ESMTP id 297ED8D0001 for ; Wed, 12 Aug 2020 08:46:37 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id DF6B22496 for ; Wed, 12 Aug 2020 12:46:36 +0000 (UTC) X-FDA: 77141890392.08.eggs37_310f29c26feb Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin08.hostedemail.com (Postfix) with ESMTP id C64621819E785 for ; Wed, 12 Aug 2020 12:46:36 +0000 (UTC) X-HE-Tag: eggs37_310f29c26feb X-Filterd-Recvd-Size: 2923 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Wed, 12 Aug 2020 12:46:36 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BE4FD31B; Wed, 12 Aug 2020 05:46:35 -0700 (PDT) Received: from [10.163.66.87] (unknown [10.163.66.87]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DF5973F70D; Wed, 12 Aug 2020 05:46:33 -0700 (PDT) Subject: Re: [PATCH 08/16] debug_vm_pgtable/set_pmd: Don't use set_pmd_at to update an existing pmd entry To: "Aneesh Kumar K.V" , linux-mm@kvack.org, akpm@linux-foundation.org Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org References: <20200812063358.369514-1-aneesh.kumar@linux.ibm.com> <20200812063358.369514-8-aneesh.kumar@linux.ibm.com> From: Anshuman Khandual Message-ID: Date: Wed, 12 Aug 2020 18:16:04 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20200812063358.369514-8-aneesh.kumar@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: C64621819E785 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote: > set_pmd_at() should not be used to set a pte entry at locations that > already holds a valid pte entry. Architectures like ppc64 don't do TLB > invalidate in set_pmd_at() and hence expect it to be used to set locations > that are not a valid PTE. > > Signed-off-by: Aneesh Kumar K.V > --- > mm/debug_vm_pgtable.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c > index cd609a212dd4..60bf876081b8 100644 > --- a/mm/debug_vm_pgtable.c > +++ b/mm/debug_vm_pgtable.c > @@ -164,8 +164,6 @@ static void __init pmd_advanced_tests(struct mm_struct *mm, > pmd = READ_ONCE(*pmdp); > WARN_ON(pmd_write(pmd)); > > - pmd = pmd_mkhuge(pfn_pmd(pfn, prot)); > - set_pmd_at(mm, vaddr, pmdp, pmd); > pmdp_huge_get_and_clear(mm, vaddr, pmdp); > pmd = READ_ONCE(*pmdp); > WARN_ON(!pmd_none(pmd)); > @@ -180,12 +178,11 @@ static void __init pmd_advanced_tests(struct mm_struct *mm, > pmd = READ_ONCE(*pmdp); > WARN_ON(!(pmd_write(pmd) && pmd_dirty(pmd))); > > - pmd = pmd_mkhuge(pfn_pmd(pfn, prot)); > - set_pmd_at(mm, vaddr, pmdp, pmd); > pmdp_huge_get_and_clear_full(vma, vaddr, pmdp, 1); > pmd = READ_ONCE(*pmdp); > WARN_ON(!pmd_none(pmd)); > > + pmd = pmd_mkhuge(pfn_pmd(pfn, prot)); > pmd = pmd_mkyoung(pmd); > set_pmd_at(mm, vaddr, pmdp, pmd); > pmdp_test_and_clear_young(vma, vaddr, pmdp); > Very similar to [PATCH 3/16] wrt set_pte_at(), please fold it.