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 2731BEB64DA for ; Thu, 20 Jul 2023 10:32:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5E8FC2800EB; Thu, 20 Jul 2023 06:32:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5712628004C; Thu, 20 Jul 2023 06:32:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 412652800EB; Thu, 20 Jul 2023 06:32:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 2C3B128004C for ; Thu, 20 Jul 2023 06:32:41 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 002A8B1080 for ; Thu, 20 Jul 2023 10:32:40 +0000 (UTC) X-FDA: 81031626480.10.73221AA Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf10.hostedemail.com (Postfix) with ESMTP id 30096C0008 for ; Thu, 20 Jul 2023 10:32:38 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=WLqa6M1K; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of will@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=will@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1689849159; 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=OUON6SPXD8UlKuQH5xkLYD6nJZt43SVrKvyaSUTOtAY=; b=1t+i8BggzTHfChP/Rqa2QOfoG3MEcPXd2h/w445Bx+75PaKzy8TJ+4mgb4K69HgpH9M0z8 8S/7QdPvMrRoBbyYYZ2iV6hqvZDbXyjPaCrSKlfYkTW9ZXm/bkV8e1Uzujnng5/G/5jswo +cKSFoixquGmchfQvvxWx7ehPX4/FMk= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=WLqa6M1K; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of will@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=will@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1689849159; a=rsa-sha256; cv=none; b=ND56fsgUGjGiiTkDsaY1XbHUm+tztjHQ7A4f9IwHIwBqQx+FZK9i7qjX2dxvF7KgcZbdNP HTXuzRLmCpdW/B96NyKqto8rWowulfgXqyv8qwGU+yP0wNBhviOWqAc1huHEsty+35PjpD dGk2tgdaIg8VLL3ItyB16U02pjQgBzc= Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2718B619FD; Thu, 20 Jul 2023 10:32:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 609E1C433C8; Thu, 20 Jul 2023 10:32:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689849157; bh=hFrIlBp2xDjwZI1051zDpKcH1l8BEytCOqnbkdhdX2U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WLqa6M1Kzj1KflXtE9wcQoLVHPaMDX2RSx/Fw8r4kbz+nbZ3dNdPp53OcrsdZOnfe s9Vywjiz1qGVxnatND2unT5gE5dFxBQV8zzHnbpf9TvxWJRgwCjop8EfPzzv8xU5ar 7EC1KNqNa4MUOnq1c1DtpqC4/nN+pYPQISMJPHSEOLMqwbf0+N/2uHzE39QDCubwtF uOWsOtuM20hQ5kAHUzupKHG2LAh1pUvDIboxh1obAZy0DZm8C+1BTb/hUkM4VUk0jS ukrrssSaogtqCiS8b+YDiXV0zao+OxGaWUe3iDh63dT2cqHGQ7NFDnr7UgoifEWou3 HrGqc1I3qlPcQ== Date: Thu, 20 Jul 2023 11:32:28 +0100 From: Will Deacon To: Mark Brown Cc: Hugh Dickins , Lorenzo Stoakes , Andrew Morton , Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , Matthew Wilcox , David Hildenbrand , Suren Baghdasaryan , Qi Zheng , Yang Shi , Mel Gorman , Peter Xu , Peter Zijlstra , Yu Zhao , Alistair Popple , Ralph Campbell , Ira Weiny , Steven Price , SeongJae Park , Huang Ying , Naoya Horiguchi , Christophe Leroy , Zack Rusin , Jason Gunthorpe , Axel Rasmussen , Anshuman Khandual , Pasha Tatashin , Miaohe Lin , Minchan Kim , Christoph Hellwig , Song Liu , Thomas Hellstrom , Ryan Roberts , linux-kernel@vger.kernel.org, linux-mm@kvack.org, regressions@leemhuis.info, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 12/32] mm/vmalloc: vmalloc_to_page() use pte_offset_kernel() Message-ID: <20230720103227.GB11034@willie-the-truck> References: <696386a-84f8-b33c-82e5-f865ed6eb39@google.com> <42279f1f-7b82-40dc-8546-86171018729c@sirena.org.uk> <901ae88d-ad0c-4e9d-b199-f1566cc62a00@lucifer.local> <977ddee4-35f0-fcd1-2fd-1c3057e7ea2a@google.com> <591b5253-47f0-440c-84b6-7786ff59667d@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <591b5253-47f0-440c-84b6-7786ff59667d@sirena.org.uk> User-Agent: Mutt/1.10.1 (2018-07-13) X-Rspamd-Queue-Id: 30096C0008 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: 5o3m4yc5mkdwjwgoumuwd1o3ox6i58er X-HE-Tag: 1689849158-284312 X-HE-Meta: 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 MMCiwUI8 7PU9MxmL3Hfuhi4PZPYopJOX0V2sBuX4HxDyjeDcwsJSRuLrbxxNawKb6FVelQHFVYhNKJWYy1NJLSNW0pzy4HitEKQhMcN8i//hxwcnX2CVMH1K3vrPbJNVfuxCyAfosgNUr1bQG+RK8C+2KS9bXAxI8idVGs0lcK/X0LA7xAluM+MbpCocVv+Ss34TaUTitpVI5+tAa/sUYYxwmBnV5Vr3D1aAi6GHOxN61cJsBWK+EuANOc9V0DDlNvefGLvUbLa+xQqbeYu4n2tI2Cu4PV2n10lY4YlrvnCaJZAvFBX+FRNSav9gGibpREsTf50ti75Y+dc96zu7v6s8paHLe1AIXvA== 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 Tue, Jul 11, 2023 at 06:57:33PM +0100, Mark Brown wrote: > On Tue, Jul 11, 2023 at 09:13:18AM -0700, Hugh Dickins wrote: > > On Tue, 11 Jul 2023, Mark Brown wrote: > > > On Mon, Jul 10, 2023 at 09:34:42PM -0700, Hugh Dickins wrote: > > > > > > > I suppose I should ask you to try reverting this 0d1c81edc61e alone > > > > from 6.5-rc1: the consistency of your bisection implies that it will > > > > "fix" the issues, and it is a commit which we could drop. It makes > > > > me a little nervous, applying userspace-pagetable validation to kernel > > > > pagetables, so I don't want to drop it; and it would really be cargo- > > > > culting to drop it without understanding. But we could drop it. > > > > > > I did look at that, it doesn't revert cleanly by itself. ... > > > > Right, that ptep_get() wrapper on the next line came in on top. > > The patch to revert just 0d1c81edc61e is this: > > Still investigating but I'm pretty convinced this is nothing to do with > your commit/series and is just common or garden memory corruption that > just happens to get tickled by your changes. Sorry for the noise. Did you get to the bottom of this? If not, do you have a reliable way to reproduce the problem? I don't like the sound of memory corruption :( Will