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 922E33B1031; Tue, 8 Sep 2026 20:28:45 +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=1788899329; cv=none; b=X1VSLVhQsx2c2DJUJ1aM3Ae31dCeOoOFuBrcKdSnZrGpMhLOT4/yx0zfT/T6uSHTWKiH/+8LjPSs322w7cSD1xtp8EkzZxOGS+QqZWtj0irwQNLjqZfaiPAur7K1/JEWCGeEYhoGDqbRjgMsWd/hFtY7z3jSAfRl7oZpaG6zpEI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788899329; c=relaxed/simple; bh=S6tE0uEfipTaQVVjMdd6O5/Vs/dJ9VaNo2fdl5bbGRQ=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=A/nGNhJmhR/cs+ey7p7lA524TKJkkezQKw29HOmgaMIozsI2yIsxHhAhkRMHPerDlS7v0W49/aU7CHjiXEJRy94p8QMs0AjXsSq43M+l6mbgSCscq9ge+PjLAoIsPeR/MFP9zGZHy7hXcoGiliIOX2GONJQCc1jRkx2Km7En7NY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QIcU+TT4; 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="QIcU+TT4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 89CE71F00A3A; Tue, 8 Sep 2026 20:28:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788899324; bh=S6tE0uEfipTaQVVjMdd6O5/Vs/dJ9VaNo2fdl5bbGRQ=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=QIcU+TT4km55OlwvKPUi/HitbxQoemt2pIlAm9eZzSCggpxtY6fmb3BUKG59Q72IB roECK+TdtDGYxye1yC29XAQ9+MzdmocReFcJ4r4tkNnSykIC8SHbjqGCZINuNM37nr D2cSbqXmgDXRHbQp6RXTDcp0qGYYvoYppIzA5IJLdET/4qNPAqpeGujkjtV5M8ijU0 jAgJV0g1Pg+/PxM1JxabtVAg9sq/mcdHPEUqxJ1sbpDaqWrteDOjFNaHFUoGVN9Gz6 J4bR4d6653K+x88nBNyS0gA3sZ1XVPnzJdLwYpOE5U7mle36yWXGlWIYkJfPfZ9kaL rCccthO2hghKQ== From: sashiko-bot@kernel.org Subject: Re: [PATCH 14/39] mm/vma: add vma[_flags]_is_kernel_owned() predicates Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?TG9yZW56byBTdG9ha2VzIChBUk0p?= Cc: linux-trace-kernel@vger.kernel.org, "Oliver Upton" , linux-scsi@vger.kernel.org, linux-s390@vger.kernel.org, dri-devel@lists.freedesktop.org, bpf@vger.kernel.org, "Vasily Gorbik" , selinux@vger.kernel.org, "Christian Borntraeger" , "Heiko Carstens" , linux-perf-users@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.linux.dev, "Alexander Gordeev" , "Marc Zyngier" In-Reply-To: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-14-dacf19cce22b@kernel.org> References: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-0-dacf19cce22b@kernel.org> <20260908-b4-mmap-prepare-vma-flag-sanify-v1-14-dacf19cce22b@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 08 Sep 2026 20:28:43 +0000 Message-Id: <20260908202843.89CE71F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Rather than referring to VMA flags with uncertain meaning, add a new > predicate that explicitly describes what possession of the VMA_PFNMAP_BIT > or VMA_MIXEDMAP_BIT flags mean, and then refer to that function for > determining VMA mergeability. >=20 > Either flag means the contents of the mapping are owned by the kernel, > usually a driver, rather than by the core mm: the memory may be MMIO, > kernel-allocated pages or even ordinary pages the driver maps itself, but > the core must not populate, reclaim, migrate, copy-on-write or merge the > range on its own initiative. >=20 > We initially also include VMA_IO_BIT here, as by implication, these must = be > kernel-owned. (mlock() also sets VMA_IO_BIT transiently on ordinary VMAs > while locking them, which is addressed later in this series.) >=20 > However the intent is to in future remove this, as no mapping should be > marked as an I/O mapping without also being marked with VMA_PFNMAP_BIT. >=20 > This forms the basis of further work intended to improve how we express V= MA > properties such as this. >=20 > Also update the VMA userland tests to reflect the change. >=20 > No functional change intended. >=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=3D14