diff --git a/src/asahi/vulkan/hk_device.c b/src/asahi/vulkan/hk_device.c
index 5478e673c08..e904f80eaa9 100644
--- a/src/asahi/vulkan/hk_device.c
+++ b/src/asahi/vulkan/hk_device.c
@@ -452,6 +452,10 @@ hk_CreateDevice(VkPhysicalDevice physicalDevice,
    agx_scratch_init(&dev->dev, &dev->scratch.fs);
    agx_scratch_init(&dev->dev, &dev->scratch.cs);
 
+   u_rwlock_init(&dev->external_bos.lock);
+   util_dynarray_init(&dev->external_bos.counts, NULL);
+   util_dynarray_init(&dev->external_bos.list, NULL);
+
    return VK_SUCCESS;
 
 fail_mem_cache:
@@ -491,6 +495,10 @@ hk_DestroyDevice(VkDevice _device, const VkAllocationCallbacks *pAllocator)
    if (!dev)
       return;
 
+   util_dynarray_fini(&dev->external_bos.counts);
+   util_dynarray_fini(&dev->external_bos.list);
+   u_rwlock_destroy(&dev->external_bos.lock);
+
    hk_device_finish_meta(dev);
    hk_destroy_internal_shaders(dev, &dev->kernels, false);
    hk_destroy_internal_shaders(dev, &dev->prolog_epilog, true);
diff --git a/src/asahi/vulkan/hk_device.h b/src/asahi/vulkan/hk_device.h
index cf05b26173c..08545826d09 100644
--- a/src/asahi/vulkan/hk_device.h
+++ b/src/asahi/vulkan/hk_device.h
@@ -8,7 +8,9 @@
 #pragma once
 
 #include "asahi/lib/agx_device.h"
+#include "util/rwlock.h"
 #include "util/simple_mtx.h"
+#include "util/u_dynarray.h"
 #include "agx_bg_eot.h"
 #include "agx_pack.h"
 #include "agx_scratch.h"
@@ -107,6 +109,12 @@ struct hk_device {
    } scratch;
 
    uint32_t perftest;
+
+   struct {
+      struct u_rwlock lock;
+      struct util_dynarray list;
+      struct util_dynarray counts;
+   } external_bos;
 };
 
 VK_DEFINE_HANDLE_CASTS(hk_device, vk.base, VkDevice, VK_OBJECT_TYPE_DEVICE)
diff --git a/src/asahi/vulkan/hk_device_memory.c b/src/asahi/vulkan/hk_device_memory.c
index a0922e80176..326ced5067e 100644
--- a/src/asahi/vulkan/hk_device_memory.c
+++ b/src/asahi/vulkan/hk_device_memory.c
@@ -49,6 +49,79 @@ hk_memory_type_flags(const VkMemoryType *type,
    return flags;
 }
 
+static void
+hk_add_ext_bo_locked(struct hk_device *dev, struct agx_bo *bo)
+{
+   uint32_t id = bo->vbo_res_id;
+
+   unsigned count = util_dynarray_num_elements(&dev->external_bos.list,
+                                               struct asahi_ccmd_submit_res);
+
+   for (unsigned i = 0; i < count; i++) {
+      struct asahi_ccmd_submit_res *p = util_dynarray_element(
+         &dev->external_bos.list, struct asahi_ccmd_submit_res, i);
+
+      if (p->res_id == id) {
+         ++*util_dynarray_element(&dev->external_bos.counts, unsigned, i);
+         return;
+      }
+   }
+
+   struct asahi_ccmd_submit_res res = {
+      .res_id = id,
+      .flags = ASAHI_EXTRES_READ | ASAHI_EXTRES_WRITE,
+   };
+   util_dynarray_append(&dev->external_bos.list, struct asahi_ccmd_submit_res,
+                        res);
+   util_dynarray_append(&dev->external_bos.counts, unsigned, 1);
+}
+
+static void
+hk_add_ext_bo(struct hk_device *dev, struct agx_bo *bo)
+{
+   if (dev->dev.is_virtio) {
+      u_rwlock_wrlock(&dev->external_bos.lock);
+      hk_add_ext_bo_locked(dev, bo);
+      u_rwlock_wrunlock(&dev->external_bos.lock);
+   }
+}
+
+static void
+hk_remove_ext_bo_locked(struct hk_device *dev, struct agx_bo *bo)
+{
+   uint32_t id = bo->vbo_res_id;
+   unsigned count = util_dynarray_num_elements(&dev->external_bos.list,
+                                               struct asahi_ccmd_submit_res);
+
+   for (unsigned i = 0; i < count; i++) {
+      struct asahi_ccmd_submit_res *p = util_dynarray_element(
+         &dev->external_bos.list, struct asahi_ccmd_submit_res, i);
+
+      if (p->res_id == id) {
+         unsigned *ctr =
+            util_dynarray_element(&dev->external_bos.counts, unsigned, i);
+         if (!--*ctr) {
+            *ctr = util_dynarray_pop(&dev->external_bos.counts, unsigned);
+            *p = util_dynarray_pop(&dev->external_bos.list,
+                                   struct asahi_ccmd_submit_res);
+         }
+         return;
+      }
+   }
+
+   unreachable("BO not found");
+}
+
+static void
+hk_remove_ext_bo(struct hk_device *dev, struct agx_bo *bo)
+{
+   if (dev->dev.is_virtio) {
+      u_rwlock_wrlock(&dev->external_bos.lock);
+      hk_remove_ext_bo_locked(dev, bo);
+      u_rwlock_wrunlock(&dev->external_bos.lock);
+   }
+}
+
 VKAPI_ATTR VkResult VKAPI_CALL
 hk_GetMemoryFdPropertiesKHR(VkDevice device,
                             VkExternalMemoryHandleTypeFlagBits handleType,
@@ -146,6 +219,9 @@ hk_AllocateMemory(VkDevice device, const VkMemoryAllocateInfo *pAllocateInfo,
       }
    }
 
+   if (mem->bo->flags & (AGX_BO_SHAREABLE | AGX_BO_SHARED))
+      hk_add_ext_bo(dev, mem->bo);
+
    if (fd_info && fd_info->handleType) {
       /* From the Vulkan spec:
        *
@@ -190,6 +266,9 @@ hk_FreeMemory(VkDevice device, VkDeviceMemory _mem,
    struct hk_memory_heap *heap = &pdev->mem_heaps[type->heapIndex];
    p_atomic_add(&heap->used, -((int64_t)mem->bo->size));
 
+   if (mem->bo->flags & (AGX_BO_SHAREABLE | AGX_BO_SHARED))
+      hk_remove_ext_bo(dev, mem->bo);
+
    agx_bo_unreference(&dev->dev, mem->bo);
 
    vk_device_memory_destroy(&dev->vk, pAllocator, &mem->vk);
diff --git a/src/asahi/vulkan/hk_queue.c b/src/asahi/vulkan/hk_queue.c
index 6a991c877e1..d34d855a732 100644
--- a/src/asahi/vulkan/hk_queue.c
+++ b/src/asahi/vulkan/hk_queue.c
@@ -272,7 +272,7 @@ max_commands_per_submit(struct hk_device *dev)
 }
 
 static VkResult
-queue_submit_single(struct agx_device *dev, struct drm_asahi_submit *submit)
+queue_submit_single(struct hk_device *dev, struct drm_asahi_submit *submit)
 {
    /* Currently we don't use the result buffer or implicit sync */
    struct agx_submit_virt virt = {
@@ -280,7 +280,17 @@ queue_submit_single(struct agx_device *dev, struct drm_asahi_submit *submit)
       .extres_count = 0,
    };
 
-   int ret = dev->ops.submit(dev, submit, &virt);
+   if (dev->dev.is_virtio) {
+      u_rwlock_rdlock(&dev->external_bos.lock);
+      virt.extres_count = util_dynarray_num_elements(
+         &dev->external_bos.list, struct asahi_ccmd_submit_res);
+      virt.extres = util_dynarray_begin(&dev->external_bos.list);
+   }
+
+   int ret = dev->dev.ops.submit(&dev->dev, submit, &virt);
+
+   if (dev->dev.is_virtio)
+      u_rwlock_rdunlock(&dev->external_bos.lock);
 
    /* XXX: don't trap */
    if (ret) {
@@ -348,7 +358,7 @@ queue_submit_looped(struct hk_device *dev, struct drm_asahi_submit *submit)
          .out_sync_count = last ? submit->out_sync_count : 0,
       };
 
-      VkResult result = queue_submit_single(&dev->dev, &submit_ioctl);
+      VkResult result = queue_submit_single(dev, &submit_ioctl);
       if (result != VK_SUCCESS)
          return result;
 
@@ -520,7 +530,7 @@ queue_submit(struct hk_device *dev, struct hk_queue *queue,
    };
 
    if (command_count <= max_commands_per_submit(dev))
-      return queue_submit_single(&dev->dev, &submit_ioctl);
+      return queue_submit_single(dev, &submit_ioctl);
    else
       return queue_submit_looped(dev, &submit_ioctl);
 }