vfio: Restrict to 64-bit host platforms

[PATCH 0/2] vfio: Restrict to 64-bit host platforms

Posted by Cédric Le Goater 11 months, 2 weeks ago

Hello,

This series avoids compiling VFIO on 32-bit host platforms where it is
not needed.

Thanks,

C.

Cédric Le Goater (2):
  vfio: Make vfio-pci available on 64-bit host platforms only
  vfio: Make vfio-platform available on Aarch64 platforms only

 hw/vfio/Kconfig | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.48.1

Re: [PATCH 0/2] vfio: Restrict to 64-bit host platforms

Posted by Daniel P. Berrangé 11 months, 2 weeks ago

On Wed, Feb 26, 2025 at 09:47:19AM +0100, Cédric Le Goater wrote:
> Hello,
> 
> This series avoids compiling VFIO on 32-bit host platforms where it is
> not needed.

If it was previously enabled on 32-bit and was possible to successfully
build & use, then it needs to go through the deprecation process - we
can't just rip out features with no prior warning.

In any case this recently merged:

  commit 6d701c9bac1d3571e9ad511e01b27df7237f0b13
  Author: Richard Henderson <richard.henderson@linaro.org>
  Date:   Mon Jan 27 16:22:24 2025 -0800

    meson: Deprecate 32-bit host support

    We deprecated i686 system mode support for qemu 8.0.  However, to
    make real cleanups to TCG we need to deprecate all 32-bit hosts.

so 32-bit host support in general is nearing end of life. Given that,
I don't think we need to further limit 32-bit host for individual
features, just let it die all at once.

With regards,
Daniel
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Re: [PATCH 0/2] vfio: Restrict to 64-bit host platforms

Posted by Cédric Le Goater 11 months, 2 weeks ago

Hello

On 2/26/25 15:01, Daniel P. Berrangé wrote:
> On Wed, Feb 26, 2025 at 09:47:19AM +0100, Cédric Le Goater wrote:
>> Hello,
>>
>> This series avoids compiling VFIO on 32-bit host platforms where it is
>> not needed.
> 
> If it was previously enabled on 32-bit and was possible to successfully
> build & use, then it needs to go through the deprecation process - we
> can't just rip out features with no prior warning.

well, x86 32-bit was the host platform I was not sure about and Alex
confirmed it worked. We would need deprecation for it I agree.
  
> In any case this recently merged:
> 
>    commit 6d701c9bac1d3571e9ad511e01b27df7237f0b13
>    Author: Richard Henderson <richard.henderson@linaro.org>
>    Date:   Mon Jan 27 16:22:24 2025 -0800
> 
>      meson: Deprecate 32-bit host support
>      
>      We deprecated i686 system mode support for qemu 8.0.  However, to
>      make real cleanups to TCG we need to deprecate all 32-bit hosts.

oh. I missed that. Great, at last !

> so 32-bit host support in general is nearing end of life. Given that,
> I don't think we need to further limit 32-bit host for individual
> features, just let it die all at once.

yes. Let's do that.

Now, I have to look more closely at those patches modifying VFIO for
32-bit support.

Thanks,

C.