linux-kernel - Re: VTIO support on USB

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: <CAHXL5pdW-3P4vJf8wmUHc=VBzXsFYkHXw=6yVc-hqfY-mE8wWA@mail.gmail.com>
Date: Wed, 13 Nov 2024 12:24:01 +0530
From: Jason fab <siliconfab@...il.com>
To: Greg KH <gregkh@...uxfoundation.org>
Cc: linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: VTIO support on USB

On Wed, Nov 13, 2024 at 11:48 AM Greg KH <gregkh@...uxfoundation.org> wrote:
>
> On Wed, Nov 13, 2024 at 11:27:47AM +0530, Jason fab wrote:
> > Hello,
> >
> > I would like to know if the linux kernel usb subsystem supports
> > Virtualization based Trusted IO Management (USB VTIO)?
>
> What exactly is that, I can't seem to search for it and have not heard
> of it before.  Do you have a link to it somewhere?  Is there a USB.org
> specification published for it?

I came across the below xHCI document and am wondering if the
Linux kernel already supports it.

Here is the link to the document:
https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf
Section 4.5 USB Virtualization Based Trusted IO Management (USB VTIO):

The USB Virtualization based Trusted IO Management capability provided
by the xHC is optional functionality that enables a multi SW/HW function
ownership and access model for the various XHCI defined memory structures
and messages. As an example we can view a PCI based xHC implementation
as using the PCI defined function as the method to comply with the USB VTIO
requirements.

The PCI Bus/Device/Function (BDF) for a given PCI function is determined during
the standard PCI enumeration of devices. PCI controllers captures its BDF when
it receives a downstream Type-0 Config Write (CfgWr0) cycle targeting its
Configuration header. This latched value is used as a "Requester ID" or
“DMA Identification” for all transactions initiated by the controller.
The PCI BDF
which is determined by the standard PCI discovery/enumeration process will be
referred to as the Primary DMA-ID.
>
> thanks,
>
> greg k-h