linux-kernel - Re: [PATCH v3 1/4] iommu: Introduce device_iommu

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]

Message-ID: <20220406052812.GA10507@lst.de>
Date:   Wed, 6 Apr 2022 07:28:12 +0200
From:   Christoph Hellwig <hch@....de>
To:     Robin Murphy <robin.murphy@....com>
Cc:     joro@...tes.org, baolu.lu@...ux.intel.com,
        andreas.noever@...il.com, michael.jamet@...el.com,
        mika.westerberg@...ux.intel.com, YehezkelShB@...il.com,
        iommu@...ts.linux-foundation.org, linux-usb@...r.kernel.org,
        linux-kernel@...r.kernel.org, mario.limonciello@....com, hch@....de
Subject: Re: [PATCH v3 1/4] iommu: Introduce device_iommu_capable()

On Tue, Apr 05, 2022 at 11:41:01AM +0100, Robin Murphy wrote:
> iommu_capable() only really works for systems where all IOMMU instances
> are completely homogeneous, and all devices are IOMMU-mapped. Implement
> the new variant which can give an accurate answer for whichever device
> the caller is actually interested in.
> 
> Signed-off-by: Robin Murphy <robin.murphy@....com>
> ---
> 
> v3: New patch; now that the dev_iommu_ops() work has landed we can go
>     straight to a proper implementation. Also s/dev/device/ to match
>     the precedent of device_iommu_mapped() for the public API.

I'm a little worrited about a method with a parameter than can be
NULL.

Also usnic, vmd, and vdpa really want to use your new
device_iommu_capable as they check based on a device.  Just VFIO
is special as usual..