On 2/23/24 7:03 PM, Kui-Feng Lee wrote:
+static void bpf_struct_ops_map_free_image(struct bpf_struct_ops_map *st_map)
+{
+ int i;
+ void *image;
+
+ bpf_jit_uncharge_modmem(PAGE_SIZE * st_map->image_pages_cnt);
+ for (i = 0; i < st_map->image_pages_cnt; i++) {
+ image = st_map->image_pages[i];
+ arch_free_bpf_trampoline(image, PAGE_SIZE);
+ }
+ st_map->image_pages_cnt = 0;
+}
+
[ ... ]
@@ -133,7 +128,8 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
err = bpf_struct_ops_prepare_trampoline(tlinks, link,
&st_ops->func_models[op_idx],
&dummy_ops_test_ret_function,
- image, image + PAGE_SIZE);
+ &image, &image_off,
+ true);
if (err < 0)
goto out;
@@ -147,6 +143,8 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
err = -EFAULT;
out:
kfree(args);
+ if (image)
+ bpf_jit_uncharge_modmem(PAGE_SIZE);
arch_free_bpf_trampoline(image, PAGE_SIZE);
It seems my last reply on v2 has crossed over with v3.
The bpf_struct_ops_free_trampoline() highlighted in my last reply should
address your concern in v2 that the caller needs to remember
the bpf_jit_uncharge_modmem here.
I think the trampoline alloc(aka prepare here)/free pair that you also
suggested in v2 discussion is a nice match here and work as a
charge+alloc and uncharge+free pair.
if (link)
bpf_link_put(&link->link);
