linux-kernel - Re: [PATCH v3 01/18] nitro_enclaves: Add ioctl interface definition

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: <d639afa5-cca6-3707-4c80-40ee1bf5bcb5@amazon.com>
Date:   Mon, 1 Jun 2020 10:20:18 +0300
From:   "Paraschiv, Andra-Irina" <andraprs@...zon.com>
To:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Stefan Hajnoczi <stefanha@...il.com>
CC:     <linux-kernel@...r.kernel.org>,
        Anthony Liguori <aliguori@...zon.com>,
        Colm MacCarthaigh <colmmacc@...zon.com>,
        Bjoern Doebel <doebel@...zon.de>,
        David Woodhouse <dwmw@...zon.co.uk>,
        Frank van der Linden <fllinden@...zon.com>,
        Alexander Graf <graf@...zon.de>,
        Martin Pohlack <mpohlack@...zon.de>,
        Matt Wilson <msw@...zon.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Balbir Singh <sblbir@...zon.com>,
        Stefano Garzarella <sgarzare@...hat.com>,
        Stefan Hajnoczi <stefanha@...hat.com>,
        Stewart Smith <trawets@...zon.com>,
        Uwe Dannowski <uwed@...zon.de>, <kvm@...r.kernel.org>,
        <ne-devel-upstream@...zon.com>
Subject: Re: [PATCH v3 01/18] nitro_enclaves: Add ioctl interface definition



On 01/06/2020 06:02, Benjamin Herrenschmidt wrote:
> On Wed, 2020-05-27 at 09:49 +0100, Stefan Hajnoczi wrote:
>> What about feature bits or a API version number field? If you add
>> features to the NE driver, how will userspace detect them?
>>
>> Even if you intend to always compile userspace against the exact kernel
>> headers that the program will run on, it can still be useful to have an
>> API version for informational purposes and to easily prevent user
>> errors (running a new userspace binary on an old kernel where the API is
>> different).
>>
>> Finally, reserved struct fields may come in handy in the future. That
>> way userspace and the kernel don't need to explicitly handle multiple
>> struct sizes.
> Beware, Greg might disagree :)
>
> That said, yes, at least a way to query the API version would be
> useful.

I see there are several thoughts with regard to extensions possibilities. :)

I added an ioctl for getting the API version, we have now a way to query 
that info. Also, I updated the sample in this patch series to check for 
the API version.

Thanks,
Andra



Amazon Development Center (Romania) S.R.L. registered office: 27A Sf. Lazar Street, UBC5, floor 2, Iasi, Iasi County, 700045, Romania. Registered in Romania. Registration number J22/2621/2005.