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Piccoli" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , x86@kernel.org, "H . Peter Anvin" Message-Id: <361838e6-76e6-4ad3-95ab-994a56bf5f9e@app.fastmail.com> In-Reply-To: References: <20260616-efi_timeout-v3-0-76dd1d26657b@debian.org> Subject: Re: [PATCH v3 0/7] efi/runtime-wrappers: bound the wait for EFI runtime service calls Content-Type: text/plain Content-Transfer-Encoding: 7bit On Wed, 1 Jul 2026, at 15:28, Breno Leitao wrote: > 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? > This looks fine now, apologies for the delayed response. I've queued this up for v7.3