From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 802383BF679; Tue, 8 Sep 2026 20:36:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788899787; cv=none; b=jTB62xeu3FFbvVc0Jm/Q6gp3hhEJcX3FYp8cY7oUIzfZcdeAh4sWaX4oaPqWbvRCmfBGDwMD67qidJLZ2kCqMFL11ecZgsdyi6x8aZPuBiTs4vHyiewZR153vccIYOkTf72urr6UpTrjVuAh5HloB38sa29BeeJPnj7fk+WsjcM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788899787; c=relaxed/simple; bh=wAJ7ikObQ7BdyD8JmXGdd6lEUfR3W8m2ceywh5stGKo=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=U1JfBoqGj8PZk8PAOB1cpNcBPaYMhvb/6vKxQSWjZ7WOGmyW2v1Goe2ENcdBaGk1C4meT0UymaM+tO0p3+kBMJdqjI4xDbJE7CKFxU7E53dPxzAD023jobti1jl2LQT1eP7GwRGqjWfVO1f6+XgwktIIl8lAg3r7GW7AGnaVdTY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Vw+3Z/GT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Vw+3Z/GT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E7401F00A3D; Tue, 8 Sep 2026 20:36:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788899785; bh=wAJ7ikObQ7BdyD8JmXGdd6lEUfR3W8m2ceywh5stGKo=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Vw+3Z/GTh+Dohhq4+9hT2hyhF257D90BGoxNyy/dMiyI/kx8l6o6yVGHmfV6TsCbu QJrR/OaDvqjzK6rjaBrKBmWKgVL/Q7kn9hHdw9Yli24KxnWoBB/40l/JJQKCI9AM3c jDuNOhAciZQLyDR5AIG4nLKerI+QUAy1b9L1JOqJM7pbEh1f/xZ2yfRPm+OSXyJFtC 3rpdr03OoNwCl+Y0FoCgxz7P5cjya9oXD2mhS23ex3fN17k/sqm1E6HiawWTZoDkkZ RAvKOnbiNyGtmQfyRwUQA0S4cRYW+mG98TCfG40v4QN0a11r/k8Sgu3XfmUZVckyR4 Irs0EZPvowRcg== From: sashiko-bot@kernel.org Subject: Re: [PATCH 20/39] mm/gup: error out early on !VMA_MAYREAD_BIT VMAs Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?TG9yZW56byBTdG9ha2VzIChBUk0p?= Cc: "Christian Borntraeger" , linux-s390@vger.kernel.org, bpf@vger.kernel.org, "Oliver Upton" , dri-devel@lists.freedesktop.org, kvm@vger.kernel.org, selinux@vger.kernel.org, linux-perf-users@vger.kernel.org, "Marc Zyngier" , "Alexander Gordeev" , linux-trace-kernel@vger.kernel.org, "Vasily Gorbik" , "Heiko Carstens" , kvmarm@lists.linux.dev, linux-scsi@vger.kernel.org In-Reply-To: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-20-dacf19cce22b@kernel.org> References: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-0-dacf19cce22b@kernel.org> <20260908-b4-mmap-prepare-vma-flag-sanify-v1-20-dacf19cce22b@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 08 Sep 2026 20:36:24 +0000 Message-Id: <20260908203625.2E7401F00A3D@smtp.kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > 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/20260908-b4-mmap-pr= epare-vma-flag-sanify-v1-0-dacf19cce22b@kernel.org?part=3D20