Re: [PATCH v3] enable x2APIC without interrupt remapping under KVM

Suresh Siddha
2009-06-29T15:01:42Z

On Mon, 2009-06-29 at 06:29 -0700, Gleb Natapov wrote:
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index d1430ef..3e5b6ea 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -260,12 +260,15 @@ config SMP
>
> config X86_X2APIC
> bool "Support x2apic"
> - depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
> + depends on X86_LOCAL_APIC && X86_64

Thinking more, probably we shouldn't remove this dependency. This might
encourage people (knowingly or unknowingly) to enable x2apic without
interrupt-remapping. Can we remove this? KVM mode will still work even
if we fail to enable interrupt-remapping. So this shouldn't be an issue,
correct?

Sorry I should have commented about this before.

>
> ioapic_entries = alloc_ioapic_entries();
> if (!ioapic_entries) {
> - pr_info("Allocate ioapic_entries failed: %d\n", ret);
> - goto end;
> + pr_info("Allocate ioapic_entries failed\n");
> + return;

We should go to ir_failed ..

> }
>
> ret = save_IO_APIC_setup(ioapic_entries);
> if (ret) {
> pr_info("Saving IO-APIC state failed: %d\n", ret);
> - goto end;
> + free_ioapic_entries(ioapic_entries);
> + return;

same here.

In few hours I will be on 24 hour flight. So please bear with me for
delayed responses.

thanks,
suresh