Re: [PATCH 2/3] KVM: PPC: Fix vmx/vsx mixup in mmio emulation

On 28/12/2021 04:28, Fabiano Rosas wrote:
> Nicholas Piggin <[email protected]> writes:
> 
>> Excerpts from Fabiano Rosas's message of December 24, 2021 7:15 am:
>>> The MMIO emulation code for vector instructions is duplicated between
>>> VSX and VMX. When emulating VMX we should check the VMX copy size
>>> instead of the VSX one.
>>>
>>> Fixes: acc9eb9305fe ("KVM: PPC: Reimplement LOAD_VMX/STORE_VMX instruction ...")
>>> Signed-off-by: Fabiano Rosas <[email protected]>
>>
>> Good catch. AFAIKS handle_vmx_store needs the same treatment? If you
>> agree then
> 
> Half the bug now, half the bug next year... haha I'll send a v2.
> 
> aside:
> All this duplication is kind of annoying. I'm looking into what it would
> take to have quadword instruction emulation here as well (Alexey caught
> a bug with syskaller) and the code would be really similar. I see that
> x86 has a more generic implementation that maybe we could take advantage
> of. See "f78146b0f923 (KVM: Fix page-crossing MMIO)"

Uff. My head exploded with vsx/vmx/vec :)
But this seems to have fixed "lvx" (which is vmx, right?).

Tested with: https://github.com/aik/linux/commits/my_kvm_tests



-- 
Alexey