Re: [PATCH v3 0/7] efi/runtime-wrappers: bound the wait for EFI runtime service calls

[Breno Leitao]

Hello Ard,

On Tue, Jun 16, 2026 at 05:09:33AM -0700, Breno Leitao wrote:
> When an EFI runtime service call hangs in firmware, the kworker on
> efi_rts_wq is stuck inside the firmware call and cannot be cancelled.
> The kernel currently waits indefinitely on the completion, and the
> caller holds efi_runtime_lock for the duration, so every subsequent
> EFI runtime caller (efivarfs, NVRAM writes, set_wakeup_time, ACPI PRM
> handlers, ...) is wedged until reboot. The only externally visible
> symptom is a "workqueue lockup" message and userspace processes
> piling up uninterruptibly on the semaphore.

I'd appreciate your thoughts on this approach. Is there anything you'd
like me to adjust or improve before we move forward?

Thanks,
--breno