Thanks for giving us a nice API to UEFI! I have built a very simple demo app to test it, but my device (X12SPi-TF) behaves strangely after the app exits gracefully: I see the boot menu as expected, but I can neither start my app a second time, nor boot into the operating system on my NVMe (GRUB -> Ubuntu Server 2024). No matter what I select, after a brief glitch I get back to the boot menu. After a power reset the device works as expected again, and I can start the app once or boot into GRUB.

My app only attempts to open theDevicePath protocol on all handles that support theBlockIO protocol:

#[entry]fnmain() ->Status{    uefi::helpers::init().unwrap();info!("uefitest starting up");test_bug().unwrap();    boot::stall(10_000_000);Status::SUCCESS}fntest_bug() ->Result{info!("### Enumerating BlockIO handles ###");let block_io_handles = boot::locate_handle_buffer(SearchType::ByProtocol(&BlockIO::GUID)).unwrap();for handlein block_io_handles.iter(){letOk(_device_path_proto) = boot::open_protocol_exclusive::<DevicePath>(*handle)else{continue;};info!("DevicePath proto opened");}Ok(())}

I am testing with uefi0.35.0 with the logger, panic_handler, alloc, and global_allocator feature (rustc 1.88.0).

Is there something obvious which I am missing, or could this be a firmware bug? I anticipated that an UEFI app could be started a second time, and that I could boot into a mundane OS after running an app. Do I need to reset the environment somehow before exiting? If I omit theboot::open_protocol_exclusive::<DevicePath> call and just loop over the BlockIO protocols, everything behaves as expected, and I can boot into GRUB as expected.