linux-kernel - Re: [RFC PATCH 0/3] VFIO: capability chains

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:	Fri, 18 Dec 2015 13:05:49 +1100
From:	Alexey Kardashevskiy <aik@...abs.ru>
To:	Alex Williamson <alex.williamson@...hat.com>
Cc:	linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [RFC PATCH 0/3] VFIO: capability chains

On 11/24/2015 07:43 AM, Alex Williamson wrote:
> Please see the commit log and comments in patch 1 for a general
> explanation of the problems that this series tries to address.  The
> general problem is that we have several cases where we want to expose
> variable sized information to the user, whether it's sparse mmaps for
> a region, as implemented here, or DMA mapping ranges of an IOMMU, or
> reserved MSI mapping ranges, etc.  Extending data structures is hard;
> extending them to report variable sized data is really hard.  After
> considering several options, I think the best approach is to copy how
> PCI does capabilities.  This allows the ioctl to only expose the
> capabilities that are relevant for them, avoids data structures that
> are too complicated to parse, and avoids creating a new ioctl each
> time we think of something else that we'd like to report.  This method
> also doesn't preclude extensions to the fixed structure since the
> offset of these capabilities is entirely dynamic.
>
> Comments welcome, I'll also follow-up to the QEMU and KVM lists with
> an RFC making use of this for mmaps skipping over the MSI-X table.
> Thanks,

Out of curiosity - could this information be exposed to the userspace via 
/sys/bus/pci/devices/xxxx:xx:xx:x/vfio_xxxx? It seems not to change after 
vfio_pci driver is bound to a device.




> Alex
>
> ---
>
> Alex Williamson (3):
>        vfio: Define capability chains
>        vfio: Define sparse mmap capability for regions
>        vfio/pci: Include sparse mmap capability for MSI-X table regions
>
>
>   drivers/vfio/pci/vfio_pci.c |  101 +++++++++++++++++++++++++++++++++++++++++++
>   include/uapi/linux/vfio.h   |   53 ++++++++++++++++++++++-
>   2 files changed, 152 insertions(+), 2 deletions(-)
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
>


-- 
Alexey
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/