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 69D1D49893D; Tue, 8 Sep 2026 20:38:00 +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=1788899881; cv=none; b=sNe29yfEWuE3f8IU8Vp4k9hIJiT6aYe8Im01gPz7ZCMiHL/yWbOeF+nO2wDCwJmpNyf/K2c5dYLaDS3Nqkl7cfRaFW14SK2JvTqZouFVWlE6Qep6RCEKAz540eOEIvEj7TC1v7/NoKj6fmEA3AtzrpgUgAvUDuA3BowZQIfXtdE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788899881; c=relaxed/simple; bh=F7DmoYHsBg14zxdNM6f82a6mXZ80MX2i1zvDc4vpwg0=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=daXEGuqTVow1UHzcqDEh5civmTg5jzbu2e8HZUEsSw1B8oHex8AyI3aJ7vYKPxv0uVpyOfb20mV8zSFSCZumXw3P+k7VlqGVZmnWj/AQjDXRlK0h3tliOkfU/rNID+a7WUrmTly+rJ6r13Xa6cYA3aIzHvq2mBTeyHCoBeX5pmk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eE9GmdLD; 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="eE9GmdLD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7AD691F00A3A; Tue, 8 Sep 2026 20:37:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788899880; bh=F7DmoYHsBg14zxdNM6f82a6mXZ80MX2i1zvDc4vpwg0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=eE9GmdLDwKtb/fVSpKHf42maGv86xcNqPguLsD4Ja85IBBHdNRQWyDBDp4krhIxaT IUmNEIDghowO1nMJoInHcn7Ki2FoWqmrVSkY/tuneHPeBePBlny4eRLjcpRGqY9faj +0/0QD8toMXpPD6H3WEBSPw8qU3Frua+06CoCN+OpGLKxEZTo16QtWaVqTfdRwR6vb gwm2r+oQ3s5UK776IO/DofRpLAo9AVk529/oPLbQliUwZZ2dSG09vofCJOTnOtCFhB B6fGn+474oNFE+wPzNGiwNsIrTHk4RNxpE9ED6Kt1Z4L2Bt6zITRfb51XWPAHNprvP mmQ+xfbg3qetg== From: sashiko-bot@kernel.org Subject: Re: [PATCH 17/39] scsi: sg: convert mmap hook to mmap_prepare and rework Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?TG9yZW56byBTdG9ha2VzIChBUk0p?= Cc: dri-devel@lists.freedesktop.org, "Christian Borntraeger" , "Marc Zyngier" , "Vasily Gorbik" , linux-scsi@vger.kernel.org, "Oliver Upton" , kvm@vger.kernel.org, selinux@vger.kernel.org, "Alexander Gordeev" , "Heiko Carstens" , kvmarm@lists.linux.dev, linux-s390@vger.kernel.org, bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org In-Reply-To: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-17-dacf19cce22b@kernel.org> References: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-0-dacf19cce22b@kernel.org> <20260908-b4-mmap-prepare-vma-flag-sanify-v1-17-dacf19cce22b@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 08 Sep 2026 20:37:58 +0000 Message-Id: <20260908203759.7AD691F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: selinux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > Move from the deprecated mmap hook to the new mmap_prepare hook. >=20 > We are mapping kernel pages here, so use the discontiguous kernel mapping > mmap action to do so. >=20 > Unwind the rather confusing loop and instead map as many pages as we can = at > one time. >=20 > Note that we do not need to pay attention to rsv_schp->k_use_sg here, as > the pages are populated for the length of the buffer at > rsv_schp->page_order granularity as compound pages. >=20 > The discontiguous kernel page mapping logic handles the compound pages for > us. >=20 > sfp->mmap_called keeps the buffer stable for us. As before it is never > cleared, so a failed mmap also leaves it set. >=20 > We also remove some useless vma, vma->vm_file NULL checks - these will > always be non-NULL if you reached the mmap hook logic. >=20 > We retain log output for consistency, but change what's output on page > mapping to indicate that sg_discontig_get() does the work now. >=20 > Note that we drop the VMA_IO_BIT flag for the VMA here. It was never > necessary as we invoke alloc_pages() which gives us refcounted folios that > are fine for GUP to access (VMA_IO_BIT would prevent that). >=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=3D17