[PATCH v6 29/60] i386/tdx: Handle KVM_SYSTEM_EVENT_TDX_FATAL

Xiaoyao Li
2024-11-05T06:38:27Z

TD guest can use TDG.VP.VMCALL<REPORT_FATAL_ERROR> to request
termination. KVM translates such request into KVM_EXIT_SYSTEM_EVENT with
type of KVM_SYSTEM_EVENT_TDX_FATAL.

Add hanlder for such exit. Parse and print the error message, and
terminate the TD guest in the handler.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
Changes in v6:
- replace the patch " i386/tdx: Handle TDG.VP.VMCALL<REPORT_FATAL_ERROR>"
in v5;
---
target/i386/kvm/kvm.c | 10 ++++++++++
target/i386/kvm/tdx-stub.c | 5 +++++
target/i386/kvm/tdx.c | 24 ++++++++++++++++++++++++
target/i386/kvm/tdx.h | 2 ++
4 files changed, 41 insertions(+)

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 4fafc003e9a7..dea0f83370d5 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -6116,6 +6116,16 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
case KVM_EXIT_HYPERCALL:
ret = kvm_handle_hypercall(run);
break;
+ case KVM_EXIT_SYSTEM_EVENT:
+ switch (run->system_event.type) {
+ case KVM_SYSTEM_EVENT_TDX_FATAL:
+ ret = tdx_handle_report_fatal_error(cpu, run);
+ break;
+ default:
+ ret = -1;
+ break;
+ }
+ break;
default:
fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason);
ret = -1;
diff --git a/target/i386/kvm/tdx-stub.c b/target/i386/kvm/tdx-stub.c
index a064d583d393..b5cb6d56c46a 100644
--- a/target/i386/kvm/tdx-stub.c
+++ b/target/i386/kvm/tdx-stub.c
@@ -11,3 +11,8 @@ int tdx_parse_tdvf(void *flash_ptr, int size)
{
return -EINVAL;
}
+
+int tdx_handle_report_fatal_error(X86CPU *cpu, struct kvm_run *run)
+{
+ return -EINVAL;
+}
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index b34707e93f4d..3f44dfbf6585 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -574,6 +574,30 @@ int tdx_parse_tdvf(void *flash_ptr, int size)
return tdvf_parse_metadata(&tdx_guest->tdvf, flash_ptr, size);
}

+int tdx_handle_report_fatal_error(X86CPU *cpu, struct kvm_run *run)
+{
+ uint64_t error_code = run->system_event.data[0];
+ char *message = NULL;
+
+ if (error_code & 0xffff) {
+ error_report("TDX: REPORT_FATAL_ERROR: invalid error code: 0x%lx",
+ error_code);
+ return -1;
+ }
+
+ /* It has optional message */
+ if (run->system_event.data[2]) {
+#define TDX_FATAL_MESSAGE_MAX 64
+ message = g_malloc0(TDX_FATAL_MESSAGE_MAX + 1);
+
+ memcpy(message, &run->system_event.data[2], TDX_FATAL_MESSAGE_MAX);
+ message[TDX_FATAL_MESSAGE_MAX] = '\0';
+ }
+
+ error_report("TD guest reports fatal error. %s", message ? : "");
+ return -1;
+}
+
static bool tdx_guest_get_sept_ve_disable(Object *obj, Error **errp)
{
TdxGuest *tdx = TDX_GUEST(obj);
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index c669e0d0daca..7222a5d31359 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -6,6 +6,7 @@
#endif

#include "confidential-guest.h"
+#include "cpu.h"
#include "hw/i386/tdvf.h"

#define TYPE_TDX_GUEST "tdx-guest"
@@ -57,5 +58,6 @@ bool is_tdx_vm(void);
int tdx_pre_create_vcpu(CPUState *cpu, Error **errp);
void tdx_set_tdvf_region(MemoryRegion *tdvf_mr);
int tdx_parse_tdvf(void *flash_ptr, int size);
+int tdx_handle_report_fatal_error(X86CPU *cpu, struct kvm_run *run);

#endif /* QEMU_I386_TDX_H */
--
2.34.1