Re: [kvm-unit-tests PATCH] x86/run: Use separate "-accel" option to configure the accelerator

[Xiaoyao Li <xiaoyao.li@intel.com>]

On 6/3/2026 4:22 AM, Sean Christopherson wrote:
> On Tue, Jun 02, 2026, Sean Christopherson wrote:
>> On Tue, Jun 02, 2026, Xiaoyao Li wrote:
>>> On 5/29/2026 8:09 AM, Xiaoyao Li wrote:
>>>> On 5/28/2026 9:00 PM, Sean Christopherson wrote:
>>>>> On Thu, May 28, 2026, Xiaoyao Li wrote:
>>>>>> When configuring accelerator via machine's "accel" property, it cannot
>>>>>> pass additional ACCEL_PROPS. For example, it hits following error when
>>>>>> configuring KVM with "notify-vmexit":
>>>>>>
>>>>>>    # ACCEL="kvm,notify-vmexit=internal-error" ./x86-run x86/apic.c
>>>>>>    #   qemu-system-x86_64: Property
>>>>>> 'pc-i440fx-11.1-machine.notify- vmexit' not found
>>>>>>
>>>>>> Switch to use separate "-accel" option to configure the accelerator.
>>>>>>
>>>>>> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
>>>>>> ---
>>>>>>   x86/run | 2 +-
>>>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>>
>>>>>> diff --git a/x86/run b/x86/run
>>>>>> index dd38f14c871f..a68d469dd1b8 100755
>>>>>> --- a/x86/run
>>>>>> +++ b/x86/run
>>>>>> @@ -43,7 +43,7 @@ fi
>>>>>>   pit="-global kvm-pit.lost_tick_policy=discard"
>>>>>>   command="${qemu} --no-reboot -nodefaults $pit $pc_testdev
>>>>>> -display none -serial stdio $pci_testdev"
>>>>>> -command+=" -machine accel=$ACCEL$ACCEL_PROPS"
>>>>>> +command+=" -accel $ACCEL$ACCEL_PROPS"
>>>>>
>>>>> This breaks my setup for specifying kernel_irqchip=split.
>>>>>
>>>>>    qemu: -accel kvm,kernel_irqchip=split: Property 'kvm-
>>>>> accel.kernel_irqchip' not found
>>>>
>>>> If you switch "kernel_irqchip" to "kernel-irqchip", it should work again.
>>>>
>>>> This needs to be fixed on QEMU side. I'll look at it.
>>>
>>> Well, I feel hard to justify a QEMU "fix" for it.
>>>
>>> "kernel_irqchip" was a property of "machine" in old QEMU, and QEMU switched
>>> it to "kernel-irqchip" automatically.
>>>
>>> Then QEMU moved it to be a property of "accel", while keeping the
>>> compatibility when users configure it via "machine" that QEMU internally
>>> setting it to accel's property in this case.
>>>
>>> However, "kernel_irqchip" is only valid on "machine", but not on "accel".
>>>
>>> For this KVM unit test issue, do we need to add workaround to keep your
>>> (work-by-accident) usage working? or just kill it?
>>
>> Nah, just switch to "accel" and call it good.  I'm likely the one and only user
>> of kernel_irqchip.
> 
> There's another problem: the CET and LAM tests force -enable-kvm:
> 
>   [cet]
>   file = cet.flat
>   arch = x86_64
>   smp = 2
>   qemu_params = -enable-kvm -m 2048 -cpu host
> 
>   [lam]
>   file = lam.flat
>   arch = x86_64
>   qemu_params = -enable-kvm -cpu max
> 
> Which apparently is wired up to "-machine accel=" under the hood, because they
> get skipped with:
> 
>   SKIP cet (qemu: The -accel and "-machine accel=" options are incompatible)
>   SKIP lam (qemu: The -accel and "-machine accel=" options are incompatible)

Oh, sorry for not respond. I didn't see this mail until I decided to ping you
for this patch after I noticed you were queuing kvm-unit-test patches.

I just sent a v2, which adds one patch to handle cet and lam tests:

https://lore.kernel.org/all/20260929202434.174501-1-xiaoyao.li@intel.com/