Re: [PATCH] KVM: s390: Do not leak kernel stack data in the KVM_S390_INTERRUPT ioctl

From: David Hildenbrand
Date: Fri Sep 13 2019 - 03:37:09 EST


On 13.09.19 09:34, Thomas Huth wrote:
> On 13/09/2019 09.20, Cornelia Huck wrote:
>> On Thu, 12 Sep 2019 13:23:38 +0200
>> Thomas Huth <thuth@xxxxxxxxxx> wrote:
>>
>>> Hmm, we already talked about deprecating support for pre-3.15 kernel
>>> stuff in the past (see
>>> https://wiki.qemu.org/ChangeLog/2.12#Future_incompatible_changes for
>>> example),
>>
>> Btw: did we ever do that? I don't quite recall what code we were
>> talking about...
>
> We never really did - but we also never fixed the issue: If you run the
> current QEMU on a kernel before 3.15, it refuses to work due to the
> missing in-kernel FLIC device:
>
> Initialization of device s390-flic-kvm failed: KVM is missing capability
> KVM_CAP_DEVICE_CTR
>
> Since nobody really complained so far that running QEMU with KVM is
> still required on a kernel < 3.15, I think we could make this also
> "official" now and improve the error message a little bit, pointing the
> user to a kernel >= 3.15.

Didn't we discuss back then to clean up *QEMU* and not the *kernel*?
Especially, to wait with cleanups until somebody requests to fix
instead. I mean you could have any user space in the wild that still
makes use of these interfaces ...

--

Thanks,

David / dhildenb