linux-kernel - Re: [PATCH 2/2] iommu/ioasid: Remove custom IOASID allocator

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:   Mon, 13 Feb 2023 11:11:52 -0800
From:   Jacob Pan <jacob.jun.pan@...ux.intel.com>
To:     Jason Gunthorpe <jgg@...dia.com>
Cc:     Jean-Philippe Brucker <jean-philippe@...aro.org>,
        LKML <linux-kernel@...r.kernel.org>, iommu@...ts.linux.dev,
        Lu Baolu <baolu.lu@...ux.intel.com>,
        Joerg Roedel <joro@...tes.org>,
        Jean-Philippe Brucker <jean-philippe@...aro.com>,
        Robin Murphy <robin.murphy@....com>,
        David Woodhouse <dwmw2@...radead.org>,
        Raj Ashok <ashok.raj@...el.com>,
        "Tian, Kevin" <kevin.tian@...el.com>, Yi Liu <yi.l.liu@...el.com>,
        jacob.jun.pan@...ux.intel.com
Subject: Re: [PATCH 2/2] iommu/ioasid: Remove custom IOASID allocator

Hi Jason,

On Mon, 13 Feb 2023 12:24:15 -0400, Jason Gunthorpe <jgg@...dia.com> wrote:

> > We could also merge ioasid.c into iommu-sva.c at this point, since I
> > haven't seen any interest for having multiple IOASID sets on Arm, but
> > I'm not sure what the current plan is for vSVA on x86.  
> 
> Once the customer allocator is removed this is bascially a thin
> wrapper around xarray
> 
> So anything that needs multiple pasid spaces should just create it on
> its own directly with xarray
> 
Just wanted to double check that for devices on VT-d platforms that support
both SVA and DMA API with PASID, we will still need a single global pasid
space (due to IOTLB tagging). So this is not the "multiple pasid spaces"
case here, right?

As I replied to Jean as well, we could use the ioasid_set to separate SVA
and DMA API PASIDs.

Thanks,

Jacob