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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 33FFAC88E72 for ; Thu, 17 Sep 2026 17:30:55 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 62AE710F004; Thu, 17 Sep 2026 17:30:54 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="Ia3avcmk"; dkim-atps=neutral Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by gabe.freedesktop.org (Postfix) with ESMTPS id AAE6010F004 for ; Thu, 17 Sep 2026 17:30:53 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id E9A046020A; Thu, 17 Sep 2026 17:30:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC88D1F000FF; Thu, 17 Sep 2026 17:30:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789666252; bh=4xh76FaC1Y6V3vEMO/lt4Zv37crcHMuvNHrxjU/1JCo=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Ia3avcmkpTpvuz+wXWTipzEb3hi+te/YkFH5JTkbB3ipE+deqYcOnP9os8UQB39/j cyjG+j5XV6RzLucZrWm8ducEpdrhj/WVqgFnjQnmoGSKSuPMkT+lH1+zhV1c1R0j2e r2jdMV2orAQZXEYA4b6VrtKIhGz91X3b2bkz1ihjH1KwgocDtfVugEQ4UU3lzZyhRs 9pMAkHQA4DgvwceJH2p/PNrXUk/tBXq3zN3fSyFV6qlxKYjpv48IREEJUWkLcbyNSh d/HBfCwCqdGbz3uNYljGTxyAEGSbrXWcsC1zzllz3x5vFZU3Mk2vC9ATlO/95klaPL dvpofggkytP4Q== From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 21/40] mm/gup: error out early on !VMA_MAYREAD_BIT VMAs To: =?utf-8?b?TG9yZW56byBTdG9ha2VzIChBUk0p?= Cc: bpf@vger.kernel.org, "Alexander Gordeev" , "Heiko Carstens" , "Christian Borntraeger" , "Marc Zyngier" , "Oliver Upton" , kvmarm@lists.linux.dev, linux-trace-kernel@vger.kernel.org, kvm@vger.kernel.org, dri-devel@lists.freedesktop.org, selinux@vger.kernel.org, "Vasily Gorbik" , linux-scsi@vger.kernel.org, linux-s390@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-rdma@vger.kernel.org In-Reply-To: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-21-4583d8a23bca@kernel.org> References: <20260917-b4-mmap-prepare-vma-flag-sanify-v3-0-4583d8a23bca@kernel.org> <20260917-b4-mmap-prepare-vma-flag-sanify-v3-21-4583d8a23bca@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 17 Sep 2026 17:30:51 +0000 Message-Id: <20260917173051.CC88D1F000FF@smtp.kernel.org> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" > When populating a VMA range via the aptly named populate_vma_page_range() > an unreadable VMA will always eventually fail with -EFAULT. >=20 > That a VMA is accessible is always checked, however VMA_MAYREAD_BIT is no= t. >=20 > All user mappings always have VMA_MAYREAD_BIT set, so this check only > impacts kernel mappings. >=20 > It is implemented specifically to disallow population of uprobes XOL > mappings which are exec-only. >=20 > A nasty interaction with these mappings may occur if they are mlocked, so > actively disallow this early. >=20 > This allows a subsequent commit to remove the VM_IO check in > __mm_populate() which otherwise requires non-MMIO mappings to be wrongly > flagged simply as a workaround. >=20 > Signed-off-by: Lorenzo Stoakes (ARM) Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260917-b4-mmap-pr= epare-vma-flag-sanify-v3-0-4583d8a23bca@kernel.org?part=3D21