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 A784EC00140 for ; Sun, 21 Aug 2022 23:31:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D0C0E8E0001; Sun, 21 Aug 2022 19:31:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CBB756B0074; Sun, 21 Aug 2022 19:31:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B83148E0001; Sun, 21 Aug 2022 19:31:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id A6B8F6B0073 for ; Sun, 21 Aug 2022 19:31:23 -0400 (EDT) Received: from smtpin31.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 7EFD3140481 for ; Sun, 21 Aug 2022 23:31:23 +0000 (UTC) X-FDA: 79825198446.31.A638198 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf06.hostedemail.com (Postfix) with ESMTP id 16A62180030 for ; Sun, 21 Aug 2022 23:31:22 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 306D860DB6; Sun, 21 Aug 2022 23:31:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3F2C4C433C1; Sun, 21 Aug 2022 23:31:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1661124681; bh=93frIIZD4/yh9PJpmvMIraSV7amDnWg//cgKG28t8Ac=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=DIejz73nGK0sraa6YCTmiNxF8hiK3k38BjQWFkn31D+ghdIOUVkxt7cItO4cRpqvz G5fRavDspWQ898Ps0Po3KYXYhAQRhs29rITOflDaa1QVqF5Ea1zlTy+tiSIR3gMG0D CkeN9KOMrzZ/U8DV1PBTURCDrM8lrIelm4C5+rgY= Date: Sun, 21 Aug 2022 16:31:20 -0700 From: Andrew Morton To: John Hubbard Cc: syzbot , hughd@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, Alistair Popple , David Hildenbrand , Jason Gunthorpe Subject: Re: [syzbot] general protection fault in vma_is_shmem Message-Id: <20220821163120.df7d936c9f47b6dc875ab763@linux-foundation.org> In-Reply-To: <0004c00e-e50f-5dcf-20f9-1b8da0822bfd@nvidia.com> References: <0000000000002c73fd05e6ba3e0b@google.com> <20220821013246.a706fa7c2d8cb494efdba02e@linux-foundation.org> <0004c00e-e50f-5dcf-20f9-1b8da0822bfd@nvidia.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661124683; a=rsa-sha256; cv=none; b=GL4iMzW7oitwqinMAXRfRV1Wkt8vIKUiCqyHBcmFF0DNfu8kM0SOK06ykc9CITbYMI9RNk ndjNyVNTfKnLqGVfESW3U0huO16dm6l9MLAvO8wDR4UQlKdob8r21AUQ8auYNQGgT/buk8 YuYBS6eII+zThap2l8QKSwtJbrVPkKw= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=DIejz73n; spf=pass (imf06.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661124683; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=c1srgJM0y5eqDU45n0tELPGDKCiGyx0lUwrU4+2YEI0=; b=rot5I2929S2jSg3zU05AoL3IJGnNxgW0j78YrrlGu/HVDvVYqPkAbgi/5NgMo8JFtZ/1LT 5Liw+kP4bAbl1pRhTGZs3HfF+60BTh6aRQ/vSHP8jU2vf6l2lwlnLQHpD3VQxoIJGQ1wzu luvarNw6TNRnz9m7QskdSdES/2P98yI= X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 16A62180030 X-Rspam-User: Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=DIejz73n; spf=pass (imf06.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Stat-Signature: oifn5b4quus9b9yfiq7fpapccun5eaut X-HE-Tag: 1661124682-145923 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 Sun, 21 Aug 2022 16:18:48 -0700 John Hubbard wrote: > > vmas[] array. We haven't messed with gup.c much this time around - > > just one patch from Alistair ("mm/gup.c: simplify and fix > > check_and_migrate_movable_pages() return codes"). It does touch this > > area, but I can't immediately see how it could newly cause this. > > > > Neither can I, even after looking at both of these recent commits to > gup.c in this branch: > > commit 4d1225cd5560 ("mm/gup.c: simplify and fix > check_and_migrate_movable_pages() return codes") > > commit 0e5d6dac6b65 ("mm/gup: fix FOLL_FORCE COW security issue and > remove FOLL_COW") > > As you say, a bisection would really help here. Might https://lkml.kernel.org/r/20220821183547.950370-1-syoshida@redhat.com save us?