Still getting the following from valgrind:

fs_file_async

Syscall param io_uring_enter(sigsz) contains uninitialised byte(s)
   at 0x4993A3D: syscall (syscall.S:38)
   by 0x4F1366: uv__io_uring_enter (src/unix/linux.c:351)
   by 0x4F23A9: uv__iou_submit (src/unix/linux.c:644)
   by 0x4F24B5: uv__iou_fs_read_or_write (src/unix/linux.c:692)
   by 0x4DDAAC: uv_fs_write (src/unix/fs.c:2212)
   by 0x422F97: create_cb (test/test-fs.c:491)
   by 0x4DA38C: uv__fs_done (src/unix/fs.c:1779)
   by 0x4CDFD0: uv__work_done (src/threadpool.c:326)
   by 0x4D6433: uv__async_io (src/unix/async.c:176)
   by 0x4F2F95: uv__io_poll (src/unix/linux.c:1076)
   by 0x4D6B2D: uv_run (src/unix/core.c:417)
   by 0x42241C: run_test_fs_file_async (test/test-fs.c:915)

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