netdev - Re: [PATCH 06/16] iommu/dma: use page allocation function provided by iommu-pages.h

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Tue, 28 Nov 2023 17:50:01 -0500
From: Pasha Tatashin <pasha.tatashin@...een.com>
To: Robin Murphy <robin.murphy@....com>
Cc: akpm@...ux-foundation.org, alex.williamson@...hat.com, 
	alim.akhtar@...sung.com, alyssa@...enzweig.io, asahi@...ts.linux.dev, 
	baolu.lu@...ux.intel.com, bhelgaas@...gle.com, cgroups@...r.kernel.org, 
	corbet@....net, david@...hat.com, dwmw2@...radead.org, hannes@...xchg.org, 
	heiko@...ech.de, iommu@...ts.linux.dev, jasowang@...hat.com, 
	jernej.skrabec@...il.com, jgg@...pe.ca, jonathanh@...dia.com, joro@...tes.org, 
	kevin.tian@...el.com, krzysztof.kozlowski@...aro.org, kvm@...r.kernel.org, 
	linux-arm-kernel@...ts.infradead.org, linux-doc@...r.kernel.org, 
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org, 
	linux-mm@...ck.org, linux-rockchip@...ts.infradead.org, 
	linux-samsung-soc@...r.kernel.org, linux-sunxi@...ts.linux.dev, 
	linux-tegra@...r.kernel.org, lizefan.x@...edance.com, marcan@...can.st, 
	mhiramat@...nel.org, mst@...hat.com, m.szyprowski@...sung.com, 
	netdev@...r.kernel.org, paulmck@...nel.org, rdunlap@...radead.org, 
	samuel@...lland.org, suravee.suthikulpanit@....com, sven@...npeter.dev, 
	thierry.reding@...il.com, tj@...nel.org, tomas.mudrunka@...il.com, 
	vdumpa@...dia.com, virtualization@...ts.linux.dev, wens@...e.org, 
	will@...nel.org, yu-cheng.yu@...el.com
Subject: Re: [PATCH 06/16] iommu/dma: use page allocation function provided by iommu-pages.h

On Tue, Nov 28, 2023 at 5:34 PM Robin Murphy <robin.murphy@....com> wrote:
>
> On 2023-11-28 8:49 pm, Pasha Tatashin wrote:
> > Convert iommu/dma-iommu.c to use the new page allocation functions
> > provided in iommu-pages.h.
>
> These have nothing to do with IOMMU pagetables, they are DMA buffers and
> they belong to whoever called the corresponding dma_alloc_* function.

Hi Robin,

This is true, however, we want to account and observe the pages
allocated by IOMMU subsystem for DMA buffers, as they are essentially
unmovable locked pages. Should we separate IOMMU memory from KVM
memory all together and add another field to /proc/meminfo, something
like "iommu -> iommu pagetable and dma memory", or do we want to
export DMA memory separately from IOMMU page tables?

Since, I included DMA memory, I specifically removed mentioning of
IOMMU page tables in the most of places, and only report it as IOMMU
memory. However, since it is still bundled together with SecPageTables
it can be confusing.

Pasha