git: f493ea650e61 - main - vmm: Expose more registers to VM_GET_REGISTER

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=f493ea650e6137ba657dfa0627da1e8bb4a985e9

commit f493ea650e6137ba657dfa0627da1e8bb4a985e9
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2024-02-07 13:47:24 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-02-07 13:52:46 +0000

    vmm: Expose more registers to VM_GET_REGISTER
    
    In a follow-up revision the gdb stub will support sending an XML target
    description to gdb, which lets us send additional registers, including
    the ones added in this patch.
    
    Reviewed by:    jhb
    MFC after:      1 month
    Sponsored by:   Innovate UK
    Differential Revision:  https://reviews.freebsd.org/D43665
---
 sys/amd64/include/vmm.h    |  4 ++++
 sys/amd64/vmm/amd/vmcb.c   | 17 +++++++++++++++++
 sys/amd64/vmm/intel/vmcs.c |  5 ++++-
 sys/amd64/vmm/intel/vmx.c  | 10 +++++++++-
 4 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/sys/amd64/include/vmm.h b/sys/amd64/include/vmm.h
index 273a1a46ba04..7d5d13678122 100644
--- a/sys/amd64/include/vmm.h
+++ b/sys/amd64/include/vmm.h
@@ -98,6 +98,10 @@ enum vm_reg_name {
 	VM_REG_GUEST_DR3,
 	VM_REG_GUEST_DR6,
 	VM_REG_GUEST_ENTRY_INST_LENGTH,
+	VM_REG_GUEST_FS_BASE,
+	VM_REG_GUEST_GS_BASE,
+	VM_REG_GUEST_KGS_BASE,
+	VM_REG_GUEST_TPR,
 	VM_REG_LAST
 };
 
diff --git a/sys/amd64/vmm/amd/vmcb.c b/sys/amd64/vmm/amd/vmcb.c
index ce05c912fc6a..4bd2fae9f821 100644
--- a/sys/amd64/vmm/amd/vmcb.c
+++ b/sys/amd64/vmm/amd/vmcb.c
@@ -39,6 +39,7 @@
 
 #include "vmm_ktr.h"
 
+#include "vlapic.h"
 #include "vmcb.h"
 #include "svm.h"
 #include "svm_softc.h"
@@ -231,6 +232,22 @@ vmcb_read(struct svm_vcpu *vcpu, int ident, uint64_t *retval)
 		*retval = seg->selector;
 		break;
 
+	case VM_REG_GUEST_FS_BASE:
+	case VM_REG_GUEST_GS_BASE:
+		seg = vmcb_segptr(vmcb, ident == VM_REG_GUEST_FS_BASE ?
+		    VM_REG_GUEST_FS : VM_REG_GUEST_GS);
+		KASSERT(seg != NULL, ("%s: unable to get segment %d from VMCB",
+		    __func__, ident));
+		*retval = seg->base;
+		break;
+	case VM_REG_GUEST_KGS_BASE:
+		*retval = state->kernelgsbase;
+		break;
+
+	case VM_REG_GUEST_TPR:
+		*retval = vlapic_get_cr8(vm_lapic(vcpu->vcpu));
+		break;
+
 	case VM_REG_GUEST_GDTR:
 	case VM_REG_GUEST_IDTR:
 		/* GDTR and IDTR don't have segment selectors */
diff --git a/sys/amd64/vmm/intel/vmcs.c b/sys/amd64/vmm/intel/vmcs.c
index 52068b8eba54..35c2ee5b6eff 100644
--- a/sys/amd64/vmm/intel/vmcs.c
+++ b/sys/amd64/vmm/intel/vmcs.c
@@ -119,10 +119,13 @@ vmcs_field_encoding(int ident)
 		return (VMCS_GUEST_PDPTE3);
 	case VM_REG_GUEST_ENTRY_INST_LENGTH:
 		return (VMCS_ENTRY_INST_LENGTH);
+	case VM_REG_GUEST_FS_BASE:
+		return (VMCS_GUEST_FS_BASE);
+	case VM_REG_GUEST_GS_BASE:
+		return (VMCS_GUEST_GS_BASE);
 	default:
 		return (-1);
 	}
-
 }
 
 static int
diff --git a/sys/amd64/vmm/intel/vmx.c b/sys/amd64/vmm/intel/vmx.c
index b7c1544ac0b3..31ca9256b527 100644
--- a/sys/amd64/vmm/intel/vmx.c
+++ b/sys/amd64/vmm/intel/vmx.c
@@ -3404,8 +3404,16 @@ vmx_getreg(void *vcpui, int reg, uint64_t *retval)
 		panic("vmx_getreg: %s%d is running", vm_name(vmx->vm),
 		    vcpu->vcpuid);
 
-	if (reg == VM_REG_GUEST_INTR_SHADOW)
+	switch (reg) {
+	case VM_REG_GUEST_INTR_SHADOW:
 		return (vmx_get_intr_shadow(vcpu, running, retval));
+	case VM_REG_GUEST_KGS_BASE:
+		*retval = vcpu->guest_msrs[IDX_MSR_KGSBASE];
+		return (0);
+	case VM_REG_GUEST_TPR:
+		*retval = vlapic_get_cr8(vm_lapic(vcpu->vcpu));
+		return (0);
+	}
 
 	if (vmxctx_getreg(&vcpu->ctx, reg, retval) == 0)
 		return (0);