Initialize the IPA state of RAM. Collect the images copied into guest
RAM into a sorted list, and issue POPULATE_REALM KVM ioctls once we've
created the Realm Descriptor. The images are part of the Realm Initial
Measurement.
Signed-off-by: Jean-Philippe Brucker <jean-phili...@linaro.org>
---
v2->v3: RIPAS is now initialized separately
---
target/arm/kvm_arm.h | 14 +++++
target/arm/kvm-rme.c | 128 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 142 insertions(+)
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 8b52a881b0..67db09a424 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -255,6 +255,16 @@ int kvm_arm_rme_vm_type(MachineState *ms);
*/
int kvm_arm_rme_vcpu_init(CPUState *cs);
+/*
+ * kvm_arm_rme_init_guest_ram
+ * @base: base address of RAM
+ * @size: size of RAM
+ *
+ * If the user requested a Realm, set the base and size of guest RAM, in order
+ * to initialize the Realm IPA space.
+ */
+void kvm_arm_rme_init_guest_ram(hwaddr base, size_t size);
+
#else
/*
@@ -281,6 +291,10 @@ static inline bool kvm_arm_mte_supported(void)
return false;
}
+static inline void kvm_arm_rme_init_guest_ram(hwaddr base, size_t size)
+{
+}
+
/*
* These functions should never actually be called without KVM support.
*/
diff --git a/target/arm/kvm-rme.c b/target/arm/kvm-rme.c
index e3cc37538a..83a29421df 100644
--- a/target/arm/kvm-rme.c
+++ b/target/arm/kvm-rme.c
@@ -9,6 +9,7 @@
#include "exec/confidential-guest-support.h"
#include "hw/boards.h"
#include "hw/core/cpu.h"
+#include "hw/loader.h"
#include "kvm_arm.h"
#include "migration/blocker.h"
#include "qapi/error.h"
@@ -20,16 +21,85 @@
#define TYPE_RME_GUEST "rme-guest"
OBJECT_DECLARE_SIMPLE_TYPE(RmeGuest, RME_GUEST)
+#define RME_PAGE_SIZE qemu_real_host_page_size()
+
struct RmeGuest {
ConfidentialGuestSupport parent_obj;
+ Notifier rom_load_notifier;
+ GSList *ram_regions;
+
+ hwaddr ram_base;
+ size_t ram_size;
};
OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES(RmeGuest, rme_guest, RME_GUEST,
CONFIDENTIAL_GUEST_SUPPORT,
{ TYPE_USER_CREATABLE }, { })
+typedef struct {
+ hwaddr base;
+ hwaddr size;
+} RmeRamRegion;
+
static RmeGuest *rme_guest;
+static int rme_init_ram(hwaddr base, size_t size, Error **errp)
+{
+ int ret;
+ uint64_t start = QEMU_ALIGN_DOWN(base, RME_PAGE_SIZE);
+ uint64_t end = QEMU_ALIGN_UP(base + size, RME_PAGE_SIZE);
+ struct kvm_cap_arm_rme_init_ipa_args init_args = {
+ .init_ipa_base = start,
+ .init_ipa_size = end - start,
+ };
+
+ ret = kvm_vm_enable_cap(kvm_state, KVM_CAP_ARM_RME, 0,
+ KVM_CAP_ARM_RME_INIT_IPA_REALM,
+ (intptr_t)&init_args);
+ if (ret) {
+ error_setg_errno(errp, -ret,
+ "failed to init RAM [0x%"HWADDR_PRIx",
0x%"HWADDR_PRIx")",
+ start, end);
+ }
+
+ return ret;
+}
+
+static int rme_populate_range(hwaddr base, size_t size, bool measure,
+ Error **errp)
+{
+ int ret;
+ uint64_t start = QEMU_ALIGN_DOWN(base, RME_PAGE_SIZE);
+ uint64_t end = QEMU_ALIGN_UP(base + size, RME_PAGE_SIZE);
+ struct kvm_cap_arm_rme_populate_realm_args populate_args = {
+ .populate_ipa_base = start,
+ .populate_ipa_size = end - start,
+ .flags = measure ? KVM_ARM_RME_POPULATE_FLAGS_MEASURE : 0,
+ };
+
+ ret = kvm_vm_enable_cap(kvm_state, KVM_CAP_ARM_RME, 0,
+ KVM_CAP_ARM_RME_POPULATE_REALM,
+ (intptr_t)&populate_args);
+ if (ret) {
+ error_setg_errno(errp, -ret,
+ "failed to populate realm [0x%"HWADDR_PRIx",
0x%"HWADDR_PRIx")",
+ start, end);
+ }
+ return ret;
+}
+
+static void rme_populate_ram_region(gpointer data, gpointer err)
+{
+ Error **errp = err;
+ const RmeRamRegion *region = data;
+
+ if (*errp) {
+ return;
+ }
+
+ rme_populate_range(region->base, region->size, /* measure */ true, errp);
+}
+
static int rme_init_cpus(Error **errp)
{
int ret;
@@ -60,6 +130,16 @@ static int rme_create_realm(Error **errp)
return -1;
}
+ if (rme_init_ram(rme_guest->ram_base, rme_guest->ram_size, errp)) {
+ return -1;
+ }
+
+ g_slist_foreach(rme_guest->ram_regions, rme_populate_ram_region, errp);
+ g_slist_free_full(g_steal_pointer(&rme_guest->ram_regions), g_free);
+ if (*errp) {
+ return -1;
+ }
+
if (rme_init_cpus(errp)) {
return -1;
}
@@ -105,6 +185,43 @@ static void rme_guest_finalize(Object *obj)
{
}
+static gint rme_compare_ram_regions(gconstpointer a, gconstpointer b)
+{
+ const RmeRamRegion *ra = a;
+ const RmeRamRegion *rb = b;
+
+ g_assert(ra->base != rb->base);
+ return ra->base < rb->base ? -1 : 1;
+}
+
+static void rme_rom_load_notify(Notifier *notifier, void *data)
+{
+ RmeRamRegion *region;
+ RomLoaderNotify *rom = data;
+
+ if (rom->addr == -1) {
+ /*
+ * These blobs (ACPI tables) are not loaded into guest RAM at reset.
+ * Instead the firmware will load them via fw_cfg and measure them
+ * itself.
+ */
+ return;
+ }
+
+ region = g_new0(RmeRamRegion, 1);
+ region->base = rom->addr;
+ region->size = rom->len;
+
+ /*
+ * The Realm Initial Measurement (RIM) depends on the order in which we
+ * initialize and populate the RAM regions. To help a verifier
+ * independently calculate the RIM, sort regions by GPA.
+ */
+ rme_guest->ram_regions = g_slist_insert_sorted(rme_guest->ram_regions,
+ region,
+ rme_compare_ram_regions);
+}
+
int kvm_arm_rme_init(MachineState *ms)
{
static Error *rme_mig_blocker;
@@ -132,11 +249,22 @@ int kvm_arm_rme_init(MachineState *ms)
*/
qemu_add_vm_change_state_handler(rme_vm_state_change, NULL);
+ rme_guest->rom_load_notifier.notify = rme_rom_load_notify;
+ rom_add_load_notifier(&rme_guest->rom_load_notifier);
+
cgs->require_guest_memfd = true;
cgs->ready = true;
return 0;
}
+void kvm_arm_rme_init_guest_ram(hwaddr base, size_t size)
+{
+ if (rme_guest) {
+ rme_guest->ram_base = base;
+ rme_guest->ram_size = size;
+ }
+}
+
int kvm_arm_rme_vcpu_init(CPUState *cs)
{
ARMCPU *cpu = ARM_CPU(cs);
--
2.47.0
