[RFC,v4,17/36] i386/tdx: Parse TDVF metadata for TDX VM

Commit Message

Xiaoyao Li May 12, 2022, 3:17 a.m. UTC

TDX cannot support pflash device since it doesn't support read-only
memslot and doesn't support emulation. Load TDVF(OVMF) with -bios option
for TDs.

When boot a TD, besides load TDVF to the address below 4G, it needs
parse TDVF metadata.

Signed-off-by: Xiaoyao Li <[e-mail]>
---
 hw/i386/pc_sysfw.c         | 7 +++++++
 hw/i386/x86.c              | 3 ++-
 target/i386/kvm/tdx-stub.c | 5 +++++
 target/i386/kvm/tdx.c      | 4 ++++
 target/i386/kvm/tdx.h      | 4 ++++
 5 files changed, 22 insertions(+), 1 deletion(-)

Comments

Gerd Hoffmann May 24, 2022, 7:03 a.m. UTC | #1

On Thu, May 12, 2022 at 11:17:44AM +0800, Xiaoyao Li wrote:
> TDX cannot support pflash device since it doesn't support read-only
> memslot and doesn't support emulation. Load TDVF(OVMF) with -bios option
> for TDs.
> 
> When boot a TD, besides load TDVF to the address below 4G, it needs
> parse TDVF metadata.
> 
> Signed-off-by: Xiaoyao Li <[e-mail]>

Acked-by: Gerd Hoffmann <[e-mail]>

Patch

diff --git a/hw/i386/pc_sysfw.c b/hw/i386/pc_sysfw.c
index c8d9e71b889b..cf63434ba89d 100644
--- a/hw/i386/pc_sysfw.c
+++ b/hw/i386/pc_sysfw.c
@@ -37,6 +37,7 @@ 
 #include "hw/block/flash.h"
 #include "sysemu/kvm.h"
 #include "sev.h"
+#include "kvm/tdx.h"
 
 #define FLASH_SECTOR_SIZE 4096
 
@@ -265,5 +266,11 @@  void x86_firmware_configure(void *ptr, int size)
         }
 
         sev_encrypt_flash(ptr, size, &error_fatal);
+    } else if (is_tdx_vm()) {
+        ret = tdx_parse_tdvf(ptr, size);
+        if (ret) {
+            error_report("failed to parse TDVF for TDX VM");
+            exit(1);
+        }
     }
 }
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index 4d0b0047627d..fdf6af2f6add 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -47,6 +47,7 @@ 
 #include "hw/intc/i8259.h"
 #include "hw/rtc/mc146818rtc.h"
 #include "target/i386/sev.h"
+#include "kvm/tdx.h"
 
 #include "hw/acpi/cpu_hotplug.h"
 #include "hw/irq.h"
@@ -1115,7 +1116,7 @@  void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
     }
     bios = g_malloc(sizeof(*bios));
     memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_fatal);
-    if (sev_enabled()) {
+    if (sev_enabled() || is_tdx_vm()) {
         /*
          * The concept of a "reset" simply doesn't exist for
          * confidential computing guests, we have to destroy and
diff --git a/target/i386/kvm/tdx-stub.c b/target/i386/kvm/tdx-stub.c
index 2871de9d7b56..395a59721266 100644
--- a/target/i386/kvm/tdx-stub.c
+++ b/target/i386/kvm/tdx-stub.c
@@ -12,3 +12,8 @@  int tdx_pre_create_vcpu(CPUState *cpu)
 {
     return -EINVAL;
 }
+
+int tdx_parse_tdvf(void *flash_ptr, int size)
+{
+    return -EINVAL;
+}
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 23bc3c32b14a..2953d2728b32 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -261,6 +261,10 @@  out:
     qemu_mutex_unlock(&tdx_guest->lock);
     return r;
 }
+int tdx_parse_tdvf(void *flash_ptr, int size)
+{
+    return tdvf_parse_metadata(&tdx_guest->tdvf, flash_ptr, size);
+}
 
 /* tdx guest */
 OBJECT_DEFINE_TYPE_WITH_INTERFACES(TdxGuest,
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index 46a24ee8c7cc..12bcf25bb95b 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -6,6 +6,7 @@ 
 #endif
 
 #include "exec/confidential-guest-support.h"
+#include "hw/i386/tdvf.h"
 
 #define TYPE_TDX_GUEST "tdx-guest"
 #define TDX_GUEST(obj)  OBJECT_CHECK(TdxGuest, (obj), TYPE_TDX_GUEST)
@@ -21,6 +22,8 @@  typedef struct TdxGuest {
 
     bool initialized;
     uint64_t attributes;    /* TD attributes */
+
+    TdxFirmware tdvf;
 } TdxGuest;
 
 #ifdef CONFIG_TDX
@@ -33,5 +36,6 @@  int tdx_kvm_init(MachineState *ms, Error **errp);
 void tdx_get_supported_cpuid(uint32_t function, uint32_t index, int reg,
                              uint32_t *ret);
 int tdx_pre_create_vcpu(CPUState *cpu);
+int tdx_parse_tdvf(void *flash_ptr, int size);
 
 #endif /* QEMU_I386_TDX_H */