From: Dave Voutila <dv@sisu.io>
Subject: remove VMFUNC feature detection
To: Openbsd Tech <tech@openbsd.org>
Cc: Mike Larkin <mlarkin@openbsd.org>
Date: Mon, 07 Oct 2024 11:09:43 -0400

As part of my cleanup of VMM feature identification, I'll be cutting a
few diffs to incrementally change the logic to keep things
reviewable. This is the first.

vmm(4) doesn't implement any support for the VMFUNC instruction, so
let's remove this detection and feature tracking.

ok?

diffstat refs/heads/master refs/heads/vmm-ident
 M  sys/arch/amd64/amd64/identcpu.c     |  0+   5-
 M  sys/arch/amd64/amd64/vmm_machdep.c  |  0+  10-
 M  sys/arch/amd64/include/cpu.h        |  0+   1-

3 files changed, 0 insertions(+), 16 deletions(-)

diff refs/heads/master refs/heads/vmm-ident
commit - 4f09e5189a0c43e3ec42299f2148c5a55c78be46
commit + 51b89aecc42f46c171160c8517a18189418a2223
blob - 755e0eeaafb78d4d23605576bbdb5e08a3c69e3a
blob + ea746d1a1b075ee9a7ecdb56737862e2e25d051f
--- sys/arch/amd64/amd64/identcpu.c
+++ sys/arch/amd64/amd64/identcpu.c
@@ -952,11 +952,6 @@ cpu_check_vmm_cap(struct cpu_info *ci)
 			/* EPT available? */
 			if (msr & (IA32_VMX_ENABLE_EPT) << 32)
 				ci->ci_vmm_flags |= CI_VMM_EPT;
-			/* VM Functions available? */
-			if (msr & (IA32_VMX_ENABLE_VM_FUNCTIONS) << 32) {
-				ci->ci_vmm_cap.vcc_vmx.vmx_vm_func =
-				    rdmsr(IA32_VMX_VMFUNC);
-			}
 		}
 	}
 
blob - 7c898fb559ff864b2542b36510a250cc1100c11c
blob + 225b9e39077678ca6ef77bbfd9a0760f733da714
--- sys/arch/amd64/amd64/vmm_machdep.c
+++ sys/arch/amd64/amd64/vmm_machdep.c
@@ -7157,16 +7157,6 @@ vmx_dump_vmcs(struct vcpu *vcpu)
 		}
 
 		if (vcpu_vmx_check_cap(vcpu, IA32_VMX_PROCBASED2_CTLS,
-		    IA32_VMX_ENABLE_VM_FUNCTIONS, 1)) {
-			/* We assume all CPUs have the same VMFUNC caps */
-			if (curcpu()->ci_vmm_cap.vcc_vmx.vmx_vm_func & 0x1) {
-				vmx_dump_vmcs_field(VMCS_EPTP_LIST_ADDRESS,
-				    "EPTP List Addr");
-				DPRINTF("\n");
-			}
-		}
-
-		if (vcpu_vmx_check_cap(vcpu, IA32_VMX_PROCBASED2_CTLS,
 		    IA32_VMX_VMCS_SHADOWING, 1)) {
 			vmx_dump_vmcs_field(VMCS_VMREAD_BITMAP_ADDRESS,
 			    "VMREAD Bitmap Addr");
blob - 34ba78776fc56d39e1b6622cf267da2d9e328f20
blob + f8c415390f9e101da4abb9f7dd8b87d3fac19e88
--- sys/arch/amd64/include/cpu.h
+++ sys/arch/amd64/include/cpu.h
@@ -73,7 +73,6 @@ struct vmx {
 	uint32_t	vmx_vmxon_revision;
 	uint32_t	vmx_msr_table_size;
 	uint32_t	vmx_cr3_tgt_count;
-	uint64_t	vmx_vm_func;
 	uint8_t		vmx_has_l1_flush_msr;
 	uint64_t	vmx_invept_mode;
 };