From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-171.mta1.migadu.com (out-171.mta1.migadu.com [95.215.58.171]) (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 880162848BE; Thu, 2 Jul 2026 15:09:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783004956; cv=none; b=SttEHgqiU618H5sWf5PGwGxNP7HOji8CAo8VgQN40ppD9vL1Cy80QKVbYgnPdpoPXaO6HDq9+rIWVQ1K6m2b29XNe4ibzyBO+yfBStCnYWUaSAjTXo18sFAbzN5FA8FYowRP0i59ZdQtoHQcIQv1MQqAlPaFLwkCJV8nhJiTrts= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783004956; c=relaxed/simple; bh=yGJKHc5VaZqAcjK7B3O7FcXFuO948pn6B7TcAXQ0C7M=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qaYhc3kMy8mWR9k1S75en2G90vTNzS0Fvwcvgtd//th/SwXLBChHnNVzpE4fyokeaxAeNat9Wc0tOXNgMqs41/xv5ib4WY1ORiE49iLPqOXrYtslqx8+7aEIrGsAykBAXjmBhsbBMU5AjpeaJvC3frtWHeFOOqt37X/bCx9Njh4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Dkh9RWL9; arc=none smtp.client-ip=95.215.58.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Dkh9RWL9" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1783004941; h=from:from: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; bh=GVgi/IDW6MB0ICHH5yTujujreeH5t5fHN661xjkq/74=; b=Dkh9RWL9rMIQE6Ur1L+lFP9fWBIPUF1EBlETBXiV1FwoU/+0F4n7u3+DtwQotZKTkFazHu oHVZr/Vs+FAfYKVbUxY57cWOfPctKhbPm5r74IEfkBs57Xoqgu/OIspBSvCnXq9uEYouaN h+ygMrTbcJpYGV90L9aTDp+5SWenOgM= Date: Thu, 2 Jul 2026 23:08:32 +0800 Precedence: bulk X-Mailing-List: linux-tegra@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH 02/13] mm/vma: update do_mmap() to use vma_flags_t To: Lorenzo Stoakes Cc: akpm@linux-foundation.org, tsbogend@alpha.franken.de, maddy@linux.ibm.com, mpe@ellerman.id.au, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, l.stach@pengutronix.de, inki.dae@samsung.com, sw0312.kim@samsung.com, kyungmin.park@samsung.com, krzk@kernel.org, peter.griffin@linaro.org, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, tursulin@ursulin.net, robin.clark@oss.qualcomm.com, lumag@kernel.org, lyude@redhat.com, dakr@kernel.org, tomi.valkeinen@ideasonboard.com, hjc@rock-chips.com, heiko@sntech.de, andy.yan@rock-chips.com, thierry.reding@kernel.org, mperttunen@nvidia.com, jonathanh@nvidia.com, kraxel@redhat.com, dmitry.osipenko@collabora.com, zack.rusin@broadcom.com, matthew.brost@intel.com, thomas.hellstrom@linux.intel.com, oleksandr_andrushchenko@epam.com, deller@gmx.de, bcrl@kvack.org, viro@zeniv.linux.org.uk, brauner@kernel.org, muchun.song@linux.dev, osalvador@suse.de, david@kernel.org, ziy@nvidia.com, baolin.wang@linux.alibaba.com, liam@infradead.org, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, hughd@google.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, jannh@google.com, pfalcato@suse.de, kees@kernel.org, perex@perex.cz, tiwai@suse.com, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, dri-devel@lists.freedesktop.org, etnaviv@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, nouveau@lists.freedesktop.org, linux-rockchip@lists.infradead.org, linux-tegra@vger.kernel.org, virtualization@lists.linux.dev, intel-xe@lists.freedesktop.org, xen-devel@lists.xenproject.org, linux-fbdev@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-sound@vger.kernel.org References: <20260702111531.64883-1-lance.yang@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Lance Yang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 2026/7/2 22:16, Lorenzo Stoakes wrote: > On Thu, Jul 02, 2026 at 07:15:31PM +0800, Lance Yang wrote: [...] >> >> [...] >>> diff --git a/mm/mmap.c b/mm/mmap.c >>> index 46174e706bbe..547352183214 100644 >>> --- a/mm/mmap.c >>> +++ b/mm/mmap.c >> [...] >>> @@ -488,23 +496,27 @@ unsigned long do_mmap(struct file *file, unsigned long addr, >>> * Check to see if we are violating any seals and update VMA >>> * flags if necessary to avoid future seal violations. >>> */ >>> - err = memfd_check_seals_mmap(file, &vm_flags); >>> + err = memfd_check_seals_mmap(file, &vma_flags); >>> if (err) >>> return (unsigned long)err; >>> } else { >>> switch (flags & MAP_TYPE) { >>> case MAP_SHARED: >>> - if (vm_flags & (VM_GROWSDOWN|VM_GROWSUP)) >>> + if (vma_flags_can_grow(&vma_flags)) >>> return -EINVAL; >>> /* >>> * Ignore pgoff. >>> */ >>> pgoff = 0; >>> - vm_flags |= VM_SHARED | VM_MAYSHARE; >>> + vma_flags_set(&vma_flags, VMA_SHARED_BIT, VMA_MAYSHARE_BIT); >>> break; >>> - case MAP_DROPPABLE: >>> - if (VM_DROPPABLE == VM_NONE) >>> + case MAP_DROPPABLE: { >>> + vma_flags_t droppable = VMA_DROPPABLE; >>> + >>> + if (vma_flags_empty(&droppable)) >>> return -EOPNOTSUPP; >>> + vma_flags_set_mask(&vma_flags, droppable); >>> + >>> /* >>> * A locked or stack area makes no sense to be droppable. >>> * >>> @@ -515,23 +527,24 @@ unsigned long do_mmap(struct file *file, unsigned long addr, >>> */ >>> if (flags & (MAP_LOCKED | MAP_HUGETLB)) >>> return -EINVAL; >>> - if (vm_flags & (VM_GROWSDOWN | VM_GROWSUP)) >>> + if (vma_flags_can_grow(&vma_flags)) >>> return -EINVAL; >>> >>> - vm_flags |= VM_DROPPABLE; >> >> Old code checked VM_GROWSDOWN|VM_GROWSUP before seting VM_DROPPABLE. New >> code flips that around. Hmm, shouldn't master, just made me look twice ;) >> >> Maybe keep old order? > > I guess I feared that defining droppable above then referencing it below would > be less clear? > > Can move if you feel strongly about it, and sorry for making the move at the > same time as the general vm_flags_t -> vma_flags_t refactor as it does make that > less clear... No need to churn just for me. Thanks :)