[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation
From: |
Markus Armbruster |
Subject: |
Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation |
Date: |
Thu, 14 Apr 2016 09:36:28 +0200 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) |
"Michael S. Tsirkin" <address@hidden> writes:
> On Wed, Apr 13, 2016 at 06:17:29PM +0200, Markus Armbruster wrote:
>> "Michael S. Tsirkin" <address@hidden> writes:
>>
>> > On Wed, Apr 13, 2016 at 10:59:35AM +0200, Markus Armbruster wrote:
>> >> I have a hard time coming up with realistic unclean breakage.
>> >
>> > The issue is that Linux is now exposing fw cfg to userspace.
>> > So it's use is about to expand significantly.
>> >
>> > This is what I am trying to prevent:
>> > - in 2016, users build a guest using a path XXX outside opt.
>> > there's a warning on host, but it is not noticed.
>>
>> Amend:
>>
>> The guest treats path XXX as optional.
>>
>> > - in 2020, qemu starts using path XXX for internal purposes.
>> > - using guest from 2016 now breaks uncleanly on this new qemu
>>
>> Amend:
>>
>> when we're not specifying the optional path XXX with -fw_cfg.
>>
>> > since guest thinks it's talking to the external tool.
>>
>> Okay, that's a much more plausible scenario. The question remains
>> whether preventing it justifies the compat break and the additional
>> interface complexity.
>
> there is no break as long as people follow the rules.
-fw_cfg exists since 2.4. You can't slap rules onto it in 2.6, and
immediately claim compatibility matters only for usage following these
rules.
- [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/08
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/08
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/09
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/11
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/11
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation,
Markus Armbruster <=
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/14
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/14
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/13
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/14
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/14
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/14
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Michael S. Tsirkin, 2016/04/14
- Re: [Qemu-devel] [PATCH v3] fw_cfg: RFQDN rules, documentation, Markus Armbruster, 2016/04/15