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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90F7AC77B7D for ; Sun, 14 May 2023 18:20:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E3E28900003; Sun, 14 May 2023 14:20:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DD05B900002; Sun, 14 May 2023 14:20:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C686E900003; Sun, 14 May 2023 14:20:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id B4CB0900002 for ; Sun, 14 May 2023 14:20:33 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 450724125E for ; Sun, 14 May 2023 18:20:33 +0000 (UTC) X-FDA: 80789675946.11.42E56AB Received: from mail-yb1-f173.google.com (mail-yb1-f173.google.com [209.85.219.173]) by imf08.hostedemail.com (Postfix) with ESMTP id 5C816160015 for ; Sun, 14 May 2023 18:20:31 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=google.com header.s=20221208 header.b=3hM1VI6N; spf=pass (imf08.hostedemail.com: domain of hughd@google.com designates 209.85.219.173 as permitted sender) smtp.mailfrom=hughd@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1684088431; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=/w8Ik+B9LqquAVc24RATG4RXaBZs1t11jn/s3N/obhU=; b=l3V5bwz5u+UlVY5qxQ2qmW0Upbw0C+jZ0TcgeNrXw7qaYQLNCTeDFMYDdBENY3zHpnU/lq AY/Xeb4LOBE4nKjWo2s4djpJBWyMdjXDdUC3OjBshrVvx6mRUajSS4lpiZPdDroj4bhgmH t4JDZXJcF3VYD1kv+Wr8ngZ7oHe2W9I= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=google.com header.s=20221208 header.b=3hM1VI6N; spf=pass (imf08.hostedemail.com: domain of hughd@google.com designates 209.85.219.173 as permitted sender) smtp.mailfrom=hughd@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1684088431; a=rsa-sha256; cv=none; b=5mQ6dLU4a6MdKDqtBVf/hpbHuLw7JgBffVeKYdF2cUIz7lCj6DfUrio+m6yb5+yWG1qrk9 MTF48CcHGXsHzICAhL0CGjCAXw98fyU0kpPrXIBl5fOTRz2RRZxO2pN9VOiqCFyG8CyOAY ZwE/nOWAZBfEbk0KCpLLrJFKGKKSy+4= Received: by mail-yb1-f173.google.com with SMTP id 3f1490d57ef6-ba1815e12efso10173271276.3 for ; Sun, 14 May 2023 11:20:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1684088430; x=1686680430; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=/w8Ik+B9LqquAVc24RATG4RXaBZs1t11jn/s3N/obhU=; b=3hM1VI6NWGWu8nKjmz4E776n6/tfMkoFz07qqIrs1oaapPZVpFGqRfLcsrD2Q9+aIl lVkR5CaBLhkLbvj6PetC97KquetslVNm4ewYDv3VlmeuHTS81B9LSL8mS5hv5NNIrJ5k qfkEuu9pgy+dtpTd6GHTh0Gi0u67Y0T46ElzOPo7riZGmKUfHA7vSk0Zmd7HgvGJHxab DqbZyXByDthzzyzxr91aGkpWgNkslpXmOPPlerkZVQyLnPVqgNtVTmJy+exwCn44tZ+/ VxkE3CJ7HkShwyo4XrVtp449lbAR3UPOjv88P7k+8G1RfjN7YRQ6k8XKtpgdfILs4FOB 5kcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684088430; x=1686680430; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=/w8Ik+B9LqquAVc24RATG4RXaBZs1t11jn/s3N/obhU=; b=Q1zrVoEayX8/A3uC/aOmtoTYA6Ki+MQatzWhDkGzG5gcFWYcKqoSdp7GdtGr4o9O5s oeK0cntsIXQ30WqCXsW9f+mu5FB7iZ5RJOEOshIbfgZwtuZjQ5geURb/7tKa1IX9Tc6Z O+I5soM/7MWUz/aFFjx1je+5JG2k5RcfpGLF0iLDssaK8PdKOgW4oKPOnGl4aT4e/v2n rZz+ytVKE19GraPPRlu27pbpWrrwwzg/sB2kF0GJvbcNaCFPfsTJa4MZoVzBu+2sgGG4 Cm0FNemDVGDRtYwJP6CfKpCTKli44eQE6rFuLAbR6mH0Wb/NvwZhKgBzEJSqbSZ1wKSs l4Sg== X-Gm-Message-State: AC+VfDyZNpzHZ7y9QtbvAV1s6syGK7/azCFpYWfcrB2yV7QdpKDqLO1v ay2CyKSPx81rst+233u3yKOiNA== X-Google-Smtp-Source: ACHHUZ4uC/iK9slyVYAwsZbskAJfVUMUdzJpIRbgKgSPhKsknTzzPntrNJG85XVm7SRutl/ig2uJ2g== X-Received: by 2002:a25:abe5:0:b0:ba1:b539:a39a with SMTP id v92-20020a25abe5000000b00ba1b539a39amr27412446ybi.6.1684088430350; Sun, 14 May 2023 11:20:30 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id 192-20020a2503c9000000b00ba73c26f0d6sm1520144ybd.15.2023.05.14.11.20.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 May 2023 11:20:28 -0700 (PDT) Date: Sun, 14 May 2023 11:20:16 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.attlocal.net To: Helge Deller cc: Hugh Dickins , Andrew Morton , Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , Matthew Wilcox , David Hildenbrand , Suren Baghdasaryan , Qi Zheng , Russell King , Catalin Marinas , Will Deacon , Geert Uytterhoeven , Greg Ungerer , Michal Simek , Thomas Bogendoerfer , John David Anglin , "Aneesh Kumar K.V" , Michael Ellerman , Alexandre Ghiti , Palmer Dabbelt , Heiko Carstens , Christian Borntraeger , Claudio Imbrenda , John Paul Adrian Glaubitz , "David S. Miller" , Chris Zankel , Max Filippov , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 08/23] parisc: add pte_unmap() to balance get_ptep() In-Reply-To: Message-ID: <6de39db5-d9aa-b35a-1652-8bdf90e7df72@google.com> References: <77a5d8c-406b-7068-4f17-23b7ac53bc83@google.com> <44ebbf90-5fbb-2815-17c7-fcfe3c87d78e@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 5C816160015 X-Stat-Signature: rgde9hkzfo3u81nh8gxxobbw37buehgw X-HE-Tag: 1684088431-877810 X-HE-Meta: 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 hWKkCmUQ O9LRxXUH/7A+OjpcF4zkUHDKOzpGnK7miPt3F3s5gKA6+WjHmXSolQSYiSiNocZrGH6DlwNDeyiTlFnoWlDwW37rwNZgaRMXrRhXBo5HXzD/UYySHTSQOStYbKRT55OLYEpMgi19ko4oMtiOeZPETE585X1ew9ZDedgF3S5XG5i48Pna0iizJe0X7nK3WS3TmzAyC/NKYhjwTH7GcmwrbcfgHqYDIbfMQY7lMhj4Z89PuFSjQKKmvVG7wywSfCtp79ZnCWqyr4L5q9upqeD+53jSHLDyb0VBLJrq55RJNohlYZceOvRkZ6X3FHAZPvQe8c0uYNjgLDHToJbFZ0oCDuubvSIeM5XT6cSgyrMXB9MBO7rfQrm7ZNqW2HYbLCwwGQRLGn31Du9THvKK3nyg+ab3lATx4S++GIgd231XKVz5IztHegPeqcJIFdQ== 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 Sat, 13 May 2023, Helge Deller wrote: > Hi Hugh, > > On 5/10/23 06:52, Hugh Dickins wrote: > > To keep balance in future, remember to pte_unmap() after a successful > > get_ptep(). And (we might as well) pretend that flush_cache_pages() > > really needed a map there, to read the pfn before "unmapping". > > > > Signed-off-by: Hugh Dickins > > --- > > arch/parisc/kernel/cache.c | 26 +++++++++++++++++++++----- > > 1 file changed, 21 insertions(+), 5 deletions(-) > > > > diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c > > index 1d3b8bc8a623..b0c969b3a300 100644 > > --- a/arch/parisc/kernel/cache.c > > +++ b/arch/parisc/kernel/cache.c > > @@ -425,10 +425,15 @@ void flush_dcache_page(struct page *page) > > offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT; > > addr = mpnt->vm_start + offset; > > if (parisc_requires_coherency()) { > > + bool needs_flush = false; > > pte_t *ptep; > > > > ptep = get_ptep(mpnt->vm_mm, addr); > > - if (ptep && pte_needs_flush(*ptep)) > > + if (ptep) { > > + needs_flush = pte_needs_flush(*ptep); > > + pte_unmap(ptep); > > + } > > + if (needs_flush) > > flush_user_cache_page(mpnt, addr); > > } else { > > /* > > @@ -560,14 +565,20 @@ EXPORT_SYMBOL(flush_kernel_dcache_page_addr); > > static void flush_cache_page_if_present(struct vm_area_struct *vma, > > unsigned long vmaddr, unsigned long pfn) > > { > > - pte_t *ptep = get_ptep(vma->vm_mm, vmaddr); > > + bool needs_flush = false; > > + pte_t *ptep; > > > > /* > > * The pte check is racy and sometimes the flush will trigger > > * a non-access TLB miss. Hopefully, the page has already been > > * flushed. > > */ > > - if (ptep && pte_needs_flush(*ptep)) > > + ptep = get_ptep(vma->vm_mm, vmaddr); > > + if (ptep) { > > + needs_flush = pte_needs_flush(*ptep)) > > ^^^^^ > One ")" too much and lacks a trailing ";" > Should be: > needs_flush = pte_needs_flush(*ptep); > > With that fixed the kernel compiles and boots sucessfully on parisc. Urgh! Indeed, thanks a lot Helge: I'll fold that in. Hugh