[PATCH v10 056/108] KVM: TDX: don't request KVM_REQ_APIC_PAGE_RELOAD

isaku.yamahata
2022-10-30T06:28:43Z

From: Isaku Yamahata <isaku.yamahata@intel.com>

TDX doesn't need APIC page depending on vapic and its callback is
WARN_ON_ONCE(is_tdx). To avoid unnecessary overhead and WARN_ON_ONCE(),
skip requesting KVM_REQ_APIC_PAGE_RELOAD when TD.

WARNING: arch/x86/kvm/vmx/main.c:696 vt_set_apic_access_page_addr+0x3c/0x50 [kvm_intel]
RIP: 0010:vt_set_apic_access_page_addr+0x3c/0x50 [kvm_intel]
Call Trace:
vcpu_enter_guest+0x145d/0x24d0 [kvm]
kvm_arch_vcpu_ioctl_run+0x25d/0xcc0 [kvm]
kvm_vcpu_ioctl+0x414/0xa30 [kvm]
__x64_sys_ioctl+0xc0/0x100
do_syscall_64+0x39/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
arch/x86/kvm/x86.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3868605462ed..5dadd0f9a10e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10487,7 +10487,9 @@ void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
* Update it when it becomes invalid.
*/
apic_address = gfn_to_hva(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT);
- if (start <= apic_address && apic_address < end)
+ /* TDX doesn't need APIC page. */
+ if (kvm->arch.vm_type != KVM_X86_TDX_VM &&
+ start <= apic_address && apic_address < end)
kvm_make_all_cpus_request(kvm, KVM_REQ_APIC_PAGE_RELOAD);
}

--
2.25.1