On Wed, May 04, 2016 at 02:09:46PM -0500, Suravee Suthikulpanit wrote:
> This patch introduces AVIC-related data structure, and AVIC
> initialization code.
>
> There are three main data structures for AVIC:
> * Virtual APIC (vAPIC) backing page (per-VCPU)
> * Physical APIC ID table (per-VM)
> * Logical APIC ID table (per-VM)
>
> Currently, AVIC is disabled by default. Users can manually
> enable AVIC via kernel boot option kvm-amd.avic=1 or during
> kvm-amd module loading with parameter avic=1.
>
> Signed-off-by: Suravee Suthikulpanit <[email protected]>
> ---
> arch/x86/include/asm/kvm_host.h | 4 +
> arch/x86/include/asm/svm.h | 3 +
> arch/x86/kvm/svm.c | 224
> +++++++++++++++++++++++++++++++++++++++-
> 3 files changed, 230 insertions(+), 1 deletion(-)
...
> + * Note:
> + * AVIC hardware walks the nested page table to check permissions,
> + * but does not use the SPA address specified in the leaf page
> + * table entry since it uses address in the AVIC_BACKING_PAGE pointer
> + * field of the VMCB. Therefore, we set up the
> + * APIC_ACCESS_PAGE_PRIVATE_MEMSLOT (4KB) here.
> + */
> +static int avic_init_access_page(struct kvm_vcpu *vcpu)
> +{
> + int ret = 0;
> + struct kvm *kvm = vcpu->kvm;
> +
> + if (!kvm->arch.apic_access_page_done) {
> + ret = x86_set_memory_region(kvm,
> + APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
> + APIC_DEFAULT_PHYS_BASE,
> + PAGE_SIZE);
> + if (ret)
> + return ret;
> + kvm->arch.apic_access_page_done = true;
> + }
> +
> + return ret;
> +}
You can save yourself and indentation level:
if (kvm->arch.apic_access_page_done)
return ret;
ret = x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
APIC_DEFAULT_PHYS_BASE, PAGE_SIZE);
if (ret)
return ret;
kvm->arch.apic_access_page_done = true;
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
