DPDK patches and discussions
 help / color / mirror / Atom feed
From: Vlad Zolotarov <vladz@cloudius-systems.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] Having troubles binding an SR-IOV VF to uio_pci_generic on Amazon instance
Date: Wed, 30 Sep 2015 22:10:57 +0300	[thread overview]
Message-ID: <560C33C1.7030202@cloudius-systems.com> (raw)
In-Reply-To: <560C32CC.90708@cloudius-systems.com>



On 09/30/15 22:06, Vlad Zolotarov wrote:
>
>
> On 09/30/15 21:55, Michael S. Tsirkin wrote:
>> On Wed, Sep 30, 2015 at 09:15:56PM +0300, Vlad Zolotarov wrote:
>>>
>>> On 09/30/15 18:26, Michael S. Tsirkin wrote:
>>>> On Wed, Sep 30, 2015 at 03:50:09PM +0300, Vlad Zolotarov wrote:
>>>>> How not virtualizing iommu forces "all or nothing" approach?
>>>> Looks like you can't limit an assigned device to only access part of
>>>> guest memory that belongs to a given process.  Either let it access 
>>>> all
>>>> of guest memory ("all") or don't assign the device ("nothing").
>>> Ok. A question then: can u limit the assigned device to only access 
>>> part of
>>> the guest memory even if iommu was virtualized?
>> That's exactly what an iommu does - limit the device io access to 
>> memory.
>
> If it does - it will continue to do so with or without the patch and 
> if it doesn't (for any reason) it won't do it even without the patch.
> So, again, the above (rhetorical) question stands. ;)
>
> I think Avi has already explained quite in detail why security is 
> absolutely a non issue in regard to this patch or in regard to UIO in 
> general. Security has to be enforced by some other  means like iommu.
>
>>
>>> How would iommu
>>> virtualization change anything?
>> Kernel can use an iommu to limit device access to memory of
>> the controlling application.
>
> Ok, this is obvious but what it has to do with enabling using 
> MSI/MSI-X interrupts support in uio_pci_generic? kernel may continue 
> to limit the above access with this support as well.
>
>>
>>> And why do we care about an assigned device
>>> to be able to access all Guest memory?
>> Because we want to be reasonably sure a kernel memory corruption
>> is not a result of a bug in a userspace application.
>
> Corrupting Guest's memory due to any SW misbehavior (including bugs) 
> is a non-issue by design - this is what HV and Guest machines were 
> invented for. So, like Avi also said, instead of trying to enforce 
> nobody cares about 

Let me rephrase: by pretending enforcing some security promise that u 
don't actually fulfill... ;)

> we'd rather make the developers life easier instead (by applying the 
> not-yet-completed patch I'm working on).
>>
>

  reply	other threads:[~2015-09-30 19:10 UTC|newest]

Thread overview: 100+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-09-27  7:05 Vlad Zolotarov
2015-09-27  9:43 ` Michael S. Tsirkin
2015-09-27 10:50   ` Vladislav Zolotarov
2015-09-29 16:41   ` Vlad Zolotarov
2015-09-29 20:54     ` Michael S. Tsirkin
2015-09-29 21:46       ` Stephen Hemminger
2015-09-29 21:49         ` Michael S. Tsirkin
2015-09-30 10:37           ` Vlad Zolotarov
2015-09-30 10:58             ` Michael S. Tsirkin
2015-09-30 11:26               ` Vlad Zolotarov
     [not found]                 ` <20150930143927-mutt-send-email-mst@redhat.com>
2015-09-30 11:53                   ` Vlad Zolotarov
2015-09-30 12:03                     ` Michael S. Tsirkin
2015-09-30 12:16                       ` Vlad Zolotarov
2015-09-30 12:27                         ` Michael S. Tsirkin
2015-09-30 12:50                           ` Vlad Zolotarov
2015-09-30 15:26                             ` Michael S. Tsirkin
2015-09-30 18:15                               ` Vlad Zolotarov
2015-09-30 18:55                                 ` Michael S. Tsirkin
2015-09-30 19:06                                   ` Vlad Zolotarov
2015-09-30 19:10                                     ` Vlad Zolotarov [this message]
2015-09-30 19:11                                       ` Vlad Zolotarov
2015-09-30 19:39                                     ` Michael S. Tsirkin
2015-09-30 20:09                                       ` Vlad Zolotarov
2015-09-30 21:36                                         ` Stephen Hemminger
2015-09-30 21:53                                           ` Michael S. Tsirkin
2015-09-30 22:20                                           ` Vlad Zolotarov
2015-10-01  8:00                                           ` Vlad Zolotarov
2015-10-01 14:47                                             ` Stephen Hemminger
2015-10-01 15:03                                               ` Vlad Zolotarov
2015-09-30 13:05                           ` Avi Kivity
2015-09-30 14:39                             ` Michael S. Tsirkin
2015-09-30 14:53                               ` Avi Kivity
2015-09-30 15:21                                 ` Michael S. Tsirkin
2015-09-30 15:36                                   ` Avi Kivity
2015-09-30 20:40                                     ` Michael S. Tsirkin
2015-09-30 21:00                                       ` Avi Kivity
2015-10-01  8:44                                       ` Michael S. Tsirkin
2015-10-01  8:46                                         ` Vlad Zolotarov
2015-10-01  8:52                                         ` Avi Kivity
2015-10-01  9:15                                           ` Michael S. Tsirkin
2015-10-01  9:22                                             ` Avi Kivity
2015-10-01  9:42                                               ` Michael S. Tsirkin
2015-10-01  9:53                                                 ` Avi Kivity
2015-10-01 10:17                                                   ` Michael S. Tsirkin
2015-10-01 10:24                                                     ` Avi Kivity
2015-10-01 10:25                                                       ` Avi Kivity
2015-10-01 10:44                                                         ` Michael S. Tsirkin
2015-10-01 10:55                                                           ` Avi Kivity
2015-10-01 21:17                                                 ` Alexander Duyck
2015-10-02 13:50                                                   ` Michael S. Tsirkin
2015-10-01  9:42                                               ` Vincent JARDIN
2015-10-01  9:43                                                 ` Avi Kivity
2015-10-01  9:48                                                   ` Vincent JARDIN
2015-10-01  9:54                                                     ` Avi Kivity
2015-10-01 10:14                                                   ` Michael S. Tsirkin
2015-10-01 10:23                                                     ` Avi Kivity
2015-10-01 14:55                                                     ` Stephen Hemminger
2015-10-01 15:49                                                       ` Michael S. Tsirkin
2015-10-01 14:54                                                 ` Stephen Hemminger
2015-10-01  9:55                                               ` Michael S. Tsirkin
2015-10-01  9:59                                                 ` Avi Kivity
2015-10-01 10:38                                                   ` Michael S. Tsirkin
2015-10-01 10:50                                                     ` Avi Kivity
2015-10-01 11:09                                                       ` Michael S. Tsirkin
2015-10-01 11:20                                                         ` Avi Kivity
2015-10-01 11:27                                                           ` Michael S. Tsirkin
2015-10-01 11:32                                                             ` Avi Kivity
2015-10-01 15:01                                                               ` Stephen Hemminger
2015-10-01 15:08                                                                 ` Avi Kivity
2015-10-01 15:46                                                                 ` Michael S. Tsirkin
2015-10-01 15:11                                                               ` Michael S. Tsirkin
2015-10-01 15:19                                                                 ` Avi Kivity
2015-10-01 15:40                                                                   ` Michael S. Tsirkin
2015-10-01 11:31                                                           ` Michael S. Tsirkin
2015-10-01 11:34                                                             ` Avi Kivity
2015-10-01 11:08                                                     ` Bruce Richardson
2015-10-01 11:23                                                       ` Michael S. Tsirkin
2015-10-01 12:07                                                         ` Bruce Richardson
2015-10-01 13:14                                                           ` Michael S. Tsirkin
2015-10-01 16:04                                                             ` Michael S. Tsirkin
2015-10-01 21:02                                                             ` Alexander Duyck
2015-10-02 14:00                                                               ` Michael S. Tsirkin
2015-10-02 14:07                                                                 ` Bruce Richardson
2015-10-04  9:07                                                                   ` Michael S. Tsirkin
2015-10-02 15:56                                                                 ` Gleb Natapov
2015-10-02 16:57                                                                 ` Alexander Duyck
2015-10-01  9:15                                           ` Avi Kivity
2015-10-01  9:29                                             ` Michael S. Tsirkin
2015-10-01  9:38                                               ` Avi Kivity
2015-10-01 10:07                                                 ` Michael S. Tsirkin
2015-10-01 10:11                                                   ` Avi Kivity
2015-10-01  9:16                                         ` Michael S. Tsirkin
2015-09-30 17:28             ` Stephen Hemminger
2015-09-30 17:39               ` Michael S. Tsirkin
2015-09-30 17:43                 ` Stephen Hemminger
2015-09-30 18:50                   ` Michael S. Tsirkin
2015-09-30 20:00                     ` Gleb Natapov
2015-09-30 20:36                       ` Michael S. Tsirkin
2015-10-01  5:04                         ` Gleb Natapov
2015-09-30 17:44                 ` Gleb Natapov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=560C33C1.7030202@cloudius-systems.com \
    --to=vladz@cloudius-systems.com \
    --cc=dev@dpdk.org \
    --cc=mst@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).