[PATCH v2 3/3] KVM: x86: dump_vmcs should include the autoload/autostore MSR lists

David Edmondson
2021-02-19T14:49:37Z

When dumping the current VMCS state, include the MSRs that are being
automatically loaded/stored during VM entry/exit.

Signed-off-by: David Edmondson <david.edmondson@oracle.com>
---
arch/x86/kvm/vmx/vmx.c | 25 +++++++++++++++++++++----
arch/x86/kvm/vmx/vmx.h | 2 +-
2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 25090e3683ca..5dbaab73e576 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5754,8 +5754,19 @@ static void vmx_dump_dtsel(char *name, uint32_t limit)
vmcs_readl(limit + GUEST_GDTR_BASE - GUEST_GDTR_LIMIT));
}

-void dump_vmcs(void)
+static void vmx_dump_msrs(char *name, struct vmx_msrs *m)
{
+ unsigned int i;
+ struct vmx_msr_entry *e;
+
+ pr_err("MSR %s:\n", name);
+ for (i = 0, e = m->val; i < m->nr; ++i, ++e)
+ pr_err(" %2d: msr=0x%08x value=0x%016llx\n", i, e->index, e->value);
+}
+
+void dump_vmcs(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
u32 vmentry_ctl, vmexit_ctl;
u32 cpu_based_exec_ctrl, pin_based_exec_ctrl, secondary_exec_control;
unsigned long cr4;
@@ -5826,6 +5837,10 @@ void dump_vmcs(void)
if (secondary_exec_control & SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY)
pr_err("InterruptStatus = %04x\n",
vmcs_read16(GUEST_INTR_STATUS));
+ if (vmcs_read32(VM_ENTRY_MSR_LOAD_COUNT) > 0)
+ vmx_dump_msrs("guest autoload", &vmx->msr_autoload.guest);
+ if (vmcs_read32(VM_EXIT_MSR_STORE_COUNT) > 0)
+ vmx_dump_msrs("guest autostore", &vmx->msr_autostore.guest);

pr_err("*** Host State ***\n");
pr_err("RIP = 0x%016lx RSP = 0x%016lx\n",
@@ -5855,6 +5870,8 @@ void dump_vmcs(void)
vmexit_ctl & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL)
pr_err("PerfGlobCtl = 0x%016llx\n",
vmcs_read64(HOST_IA32_PERF_GLOBAL_CTRL));
+ if (vmcs_read32(VM_EXIT_MSR_LOAD_COUNT) > 0)
+ vmx_dump_msrs("host autoload", &vmx->msr_autoload.host);

pr_err("*** Control State ***\n");
pr_err("PinBased=%08x CPUBased=%08x SecondaryExec=%08x\n",
@@ -5954,7 +5971,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
}

if (exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) {
- dump_vmcs();
+ dump_vmcs(vcpu);
vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
vcpu->run->fail_entry.hardware_entry_failure_reason
= exit_reason;
@@ -5963,7 +5980,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
}

if (unlikely(vmx->fail)) {
- dump_vmcs();
+ dump_vmcs(vcpu);
vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
vcpu->run->fail_entry.hardware_entry_failure_reason
= vmcs_read32(VM_INSTRUCTION_ERROR);
@@ -6048,7 +6065,7 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)

unexpected_vmexit:
vcpu_unimpl(vcpu, "vmx: unexpected exit reason 0x%x\n", exit_reason);
- dump_vmcs();
+ dump_vmcs(vcpu);
vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
vcpu->run->internal.suberror =
KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON;
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 9d3a557949ac..f8a0ce74798e 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -489,6 +489,6 @@ static inline bool vmx_guest_state_valid(struct kvm_vcpu *vcpu)
return is_unrestricted_guest(vcpu) || __vmx_guest_state_valid(vcpu);
}

-void dump_vmcs(void);
+void dump_vmcs(struct kvm_vcpu *vcpu);

#endif /* __KVM_X86_VMX_H */
--
2.30.0