i386/tdx: Add TDVF memory via KVM_TDX_INIT_MEM_REGION

TDVF firmware (CODE and VARS) needs to be copied to TD's private
memory via KVM_TDX_INIT_MEM_REGION, as well as TD HOB and TEMP memory.

If the TDVF section has TDVF_SECTION_ATTRIBUTES_MR_EXTEND set in the
flag, calling KVM_TDX_EXTEND_MEMORY to extend the measurement.

After populating the TDVF memory, the original image located in shared
ramblock can be discarded.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250508150002.689633-25-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index e20ffee95507c0722b08f0ae94028e4cc9596d25..43529a9e0edbeba8cfabb400c620cb903f203593 100644 (file)
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -17,6 +17,7 @@
 #include "qom/object_interfaces.h"
 #include "crypto/hash.h"
 #include "system/system.h"
+#include "system/ramblock.h"
 
 #include "hw/i386/e820_memory_layout.h"
 #include "hw/i386/tdvf.h"
@@ -262,6 +263,9 @@ static void tdx_finalize_vm(Notifier *notifier, void *unused)
 {
     TdxFirmware *tdvf = &tdx_guest->tdvf;
     TdxFirmwareEntry *entry;
+    RAMBlock *ram_block;
+    Error *local_err = NULL;
+    int r;
 
     tdx_init_ram_entries();
 
@@ -297,6 +301,44 @@ static void tdx_finalize_vm(Notifier *notifier, void *unused)
           sizeof(TdxRamEntry), &tdx_ram_entry_compare);
 
     tdvf_hob_create(tdx_guest, tdx_get_hob_entry(tdx_guest));
+
+    for_each_tdx_fw_entry(tdvf, entry) {
+        struct kvm_tdx_init_mem_region region;
+        uint32_t flags;
+
+        region = (struct kvm_tdx_init_mem_region) {
+            .source_addr = (uint64_t)entry->mem_ptr,
+            .gpa = entry->address,
+            .nr_pages = entry->size >> 12,
+        };
+
+        flags = entry->attributes & TDVF_SECTION_ATTRIBUTES_MR_EXTEND ?
+                KVM_TDX_MEASURE_MEMORY_REGION : 0;
+
+        do {
+            error_free(local_err);
+            local_err = NULL;
+            r = tdx_vcpu_ioctl(first_cpu, KVM_TDX_INIT_MEM_REGION, flags,
+                               &region, &local_err);
+        } while (r == -EAGAIN || r == -EINTR);
+        if (r < 0) {
+            error_report_err(local_err);
+            exit(1);
+        }
+
+        if (entry->type == TDVF_SECTION_TYPE_TD_HOB ||
+            entry->type == TDVF_SECTION_TYPE_TEMP_MEM) {
+            qemu_ram_munmap(-1, entry->mem_ptr, entry->size);
+            entry->mem_ptr = NULL;
+        }
+    }
+
+    /*
+     * TDVF image has been copied into private region above via
+     * KVM_MEMORY_MAPPING. It becomes useless.
+     */
+    ram_block = tdx_guest->tdvf_mr->ram_block;
+    ram_block_discard_range(ram_block, 0, ram_block->max_length);
 }
 
 static Notifier tdx_machine_done_notify = {