[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] Qemu/KVM: Remove x2apic feature from CPU model
From: |
Paolo Bonzini |
Subject: |
Re: [Qemu-devel] [PATCH] Qemu/KVM: Remove x2apic feature from CPU model when kernel_irqchip is off |
Date: |
Fri, 26 Feb 2016 10:56:14 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 |
On 25/02/2016 16:15, Lan Tianyu wrote:
> x2apic feature is in the kvm_default_props and automatically added to all
> CPU models when KVM is enabled. But userspace devices don't support x2apic
> which can't be enabled without the in-kernel irqchip. It will trigger
> warning of "host doesn't support requested feature: CPUID.01H:ECX.x2apic
> [bit 21]" when kernel_irqchip is off. This patch is to fix it via removing
> x2apic feature when kernel_irqchip is off.
>
> Signed-off-by: Lan Tianyu <address@hidden>
> ---
> target-i386/cpu.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index c78f824..298fb62 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -2125,6 +2125,10 @@ static void x86_cpu_load_def(X86CPU *cpu,
> X86CPUDefinition *def, Error **errp)
>
> /* Special cases not set in the X86CPUDefinition structs: */
> if (kvm_enabled()) {
> + if (!kvm_irqchip_in_kernel()) {
> + x86_cpu_change_kvm_default("x2apic", "off");
> + }
> +
> x86_cpu_apply_props(cpu, kvm_default_props);
> }
>
>
Acked-by: Paolo Bonzini <address@hidden>