diff --git a/src/asahi/lib/agx_device.c b/src/asahi/lib/agx_device.c
index 745685c0e8d..07d93e50bfb 100644
--- a/src/asahi/lib/agx_device.c
+++ b/src/asahi/lib/agx_device.c
@@ -227,13 +227,13 @@ agx_bo_alloc(struct agx_device *dev, size_t size, size_t align,
 }
 
 static void
-agx_bo_mmap(struct agx_device *dev, struct agx_bo *bo)
+agx_bo_mmap(struct agx_device *dev, struct agx_bo *bo, void *fixed_addr)
 {
    assert(bo->_map == NULL && "not double mapped");
 
    struct drm_asahi_gem_mmap_offset gem_mmap_offset = {.handle =
                                                           bo->uapi_handle};
-   int ret;
+   int ret, flags;
 
    ret = drmIoctl(dev->fd, DRM_IOCTL_ASAHI_GEM_MMAP_OFFSET, &gem_mmap_offset);
    if (ret) {
@@ -241,8 +241,9 @@ agx_bo_mmap(struct agx_device *dev, struct agx_bo *bo)
       assert(0);
    }
 
-   bo->_map = os_mmap(NULL, bo->size, PROT_READ | PROT_WRITE, MAP_SHARED,
-                      dev->fd, gem_mmap_offset.offset);
+   flags = MAP_SHARED | (fixed_addr ? MAP_FIXED : 0);
+   bo->_map = os_mmap(fixed_addr, bo->size, PROT_READ | PROT_WRITE,
+                      flags, dev->fd, gem_mmap_offset.offset);
    if (bo->_map == MAP_FAILED) {
       bo->_map = NULL;
       fprintf(stderr,
diff --git a/src/asahi/lib/agx_device.h b/src/asahi/lib/agx_device.h
index aabebec93ff..17c900b67aa 100644
--- a/src/asahi/lib/agx_device.h
+++ b/src/asahi/lib/agx_device.h
@@ -74,7 +74,7 @@ typedef struct {
                               enum agx_bo_flags flags);
    int (*bo_bind)(struct agx_device *dev, struct drm_asahi_gem_bind_op *ops,
                   uint32_t count);
-   void (*bo_mmap)(struct agx_device *dev, struct agx_bo *bo);
+   void (*bo_mmap)(struct agx_device *dev, struct agx_bo *bo, void *fixed_addr);
    ssize_t (*get_params)(struct agx_device *dev, void *buf, size_t size);
    int (*submit)(struct agx_device *dev, struct drm_asahi_submit *submit,
                  struct agx_submit_virt *virt);
@@ -201,14 +201,20 @@ agx_rw_addr_to_ro(struct agx_device *dev, uint64_t addr)
 }
 
 static inline void *
-agx_bo_map(struct agx_bo *bo)
+agx_bo_map_placed(struct agx_bo *bo, void *fixed_addr)
 {
    if (!bo->_map)
-      bo->dev->ops.bo_mmap(bo->dev, bo);
+      bo->dev->ops.bo_mmap(bo->dev, bo, fixed_addr);
 
    return bo->_map;
 }
 
+static inline void *
+agx_bo_map(struct agx_bo *bo)
+{
+   return agx_bo_map_placed(bo, NULL);
+}
+
 static inline bool
 agx_has_soft_fault(struct agx_device *dev)
 {
diff --git a/src/asahi/lib/agx_device_virtio.c b/src/asahi/lib/agx_device_virtio.c
index 347faa4e26c..13e4c631c3e 100644
--- a/src/asahi/lib/agx_device_virtio.c
+++ b/src/asahi/lib/agx_device_virtio.c
@@ -190,9 +190,9 @@ agx_virtio_bo_unbind_object(struct agx_device *dev, uint32_t object_handle)
 }
 
 static void
-agx_virtio_bo_mmap(struct agx_device *dev, struct agx_bo *bo)
+agx_virtio_bo_mmap(struct agx_device *dev, struct agx_bo *bo, void *fixed_addr)
 {
-   bo->_map = vdrm_bo_map(dev->vdrm, bo->handle, bo->size, NULL);
+   bo->_map = vdrm_bo_map(dev->vdrm, bo->handle, bo->size, fixed_addr);
    if (bo->_map == MAP_FAILED) {
       bo->_map = NULL;
       fprintf(stderr, "mmap failed: result=%p size=0x%llx fd=%i\n", bo->_map,
diff --git a/src/asahi/vulkan/hk_device_memory.c b/src/asahi/vulkan/hk_device_memory.c
index 69771d2d6a7..de50861103d 100644
--- a/src/asahi/vulkan/hk_device_memory.c
+++ b/src/asahi/vulkan/hk_device_memory.c
@@ -297,7 +297,7 @@ hk_MapMemory2KHR(VkDevice device, const VkMemoryMapInfoKHR *pMemoryMapInfo,
    const VkDeviceSize size = vk_device_memory_range(
       &mem->vk, pMemoryMapInfo->offset, pMemoryMapInfo->size);
 
-   UNUSED void *fixed_addr = NULL;
+   void *fixed_addr = NULL;
    if (pMemoryMapInfo->flags & VK_MEMORY_MAP_PLACED_BIT_EXT) {
       const VkMemoryMapPlacedInfoEXT *placed_info = vk_find_struct_const(
          pMemoryMapInfo->pNext, MEMORY_MAP_PLACED_INFO_EXT);
@@ -329,7 +329,8 @@ hk_MapMemory2KHR(VkDevice device, const VkMemoryMapInfoKHR *pMemoryMapInfo,
                        "Memory object already mapped.");
    }
 
-   mem->map = agx_bo_map(mem->bo);
+   mem->map = agx_bo_map_placed(mem->bo, fixed_addr);
+   assert(!fixed_addr || mem->map == fixed_addr);
    *ppData = mem->map + offset;
 
    return VK_SUCCESS;
@@ -345,16 +346,15 @@ hk_UnmapMemory2KHR(VkDevice device,
       return VK_SUCCESS;
 
    if (pMemoryUnmapInfo->flags & VK_MEMORY_UNMAP_RESERVE_BIT_EXT) {
-      unreachable("todo");
-#if 0
       VK_FROM_HANDLE(hk_device, dev, device);
 
-      int err = agx_bo_overmap(mem->bo, mem->map);
-      if (err) {
+      void *err = mmap(mem->bo->_map, mem->bo->size, PROT_NONE,
+                       MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
+      if (err == MAP_FAILED) {
          return vk_errorf(dev, VK_ERROR_MEMORY_MAP_FAILED,
                           "Failed to map over original mapping");
       }
-#endif
+      mem->bo->_map = NULL;
    } else {
       if (mem->bo->_map) {
          munmap(mem->bo->_map, mem->bo->size);
diff --git a/src/asahi/vulkan/hk_physical_device.c b/src/asahi/vulkan/hk_physical_device.c
index b63d1b8270c..0f518d02d9e 100644
--- a/src/asahi/vulkan/hk_physical_device.c
+++ b/src/asahi/vulkan/hk_physical_device.c
@@ -163,7 +163,7 @@ hk_get_device_extensions(const struct hk_instance *instance,
       .EXT_inline_uniform_block = true,
       .EXT_line_rasterization = true,
       .EXT_load_store_op_none = true,
-      .EXT_map_memory_placed = false,
+      .EXT_map_memory_placed = true,
       .EXT_memory_budget = false,
       .EXT_multi_draw = true,
       .EXT_mutable_descriptor_type = true,
@@ -535,9 +535,9 @@ hk_get_device_features(
       .minLod = true,
 
       /* VK_EXT_map_memory_placed */
-      .memoryMapPlaced = false,
+      .memoryMapPlaced = true,
       .memoryMapRangePlaced = false,
-      .memoryUnmapReserve = false,
+      .memoryUnmapReserve = true,
 
       /* VK_EXT_multi_draw */
       .multiDraw = true,