linux-kernel - RE: [RFC v16 1/9] iommu: Introduce attach/detach_pasid

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 for Android: free password hash cracker in your pocket

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

Date:   Thu, 9 Dec 2021 03:59:57 +0000
From:   "Tian, Kevin" <kevin.tian@...el.com>
To:     Jason Gunthorpe <jgg@...dia.com>,
        Jean-Philippe Brucker <jean-philippe@...aro.org>
CC:     Eric Auger <eric.auger@...hat.com>,
        Lu Baolu <baolu.lu@...ux.intel.com>,
        Joerg Roedel <joro@...tes.org>,
        "peter.maydell@...aro.org" <peter.maydell@...aro.org>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "vivek.gautam@....com" <vivek.gautam@....com>,
        "kvmarm@...ts.cs.columbia.edu" <kvmarm@...ts.cs.columbia.edu>,
        "eric.auger.pro@...il.com" <eric.auger.pro@...il.com>,
        "Raj, Ashok" <ashok.raj@...el.com>,
        "maz@...nel.org" <maz@...nel.org>,
        "vsethi@...dia.com" <vsethi@...dia.com>,
        "zhangfei.gao@...aro.org" <zhangfei.gao@...aro.org>,
        "will@...nel.org" <will@...nel.org>,
        "alex.williamson@...hat.com" <alex.williamson@...hat.com>,
        "wangxingang5@...wei.com" <wangxingang5@...wei.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "lushenming@...wei.com" <lushenming@...wei.com>,
        "iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
        "robin.murphy@....com" <robin.murphy@....com>
Subject: RE: [RFC v16 1/9] iommu: Introduce attach/detach_pasid_table API

> From: Tian, Kevin
> Sent: Thursday, December 9, 2021 10:58 AM
> 
> For ARM it's SMMU's PASID table format. There is no step-2 since PASID
> is already within the address space covered by the user PASID table.
> 

One correction here. 'no step-2' is definitely wrong here as it means
more than user page table in your plan (e.g. dpdk).

To simplify it what I meant is:

iommufd reports how many 'user page tables' are supported given a device.

ARM always reports only one can be supported, and it must be created in 
PASID table format. tagged by RID.

Intel reports one in step1 (tagged by RID), and N in step2 (tagged by
RID+PASID). A special flag in attach call allows the user to specify the
additional PASID routing info for a 'user page table'.

Thanks
Kevin