Re: [PATCH] PCI/AER: Use IRQF_NO_THREAD on aer_irq

[Lukas Wunner <lukas@wunner.de>]

On Tue, Sep 02, 2025 at 05:44:41PM -0500, Crystal Wood wrote:
> On PREEMPT_RT, currently both aer_irq and aer_isr run in separate threads,

My understanding is that if request_threaded_irq() is passed both a
non-NULL handler and a non-NULL thread_fn, the former runs in hardirq
context and the latter in kthread context.  Even on PREEMPT_RT.

So how can aer_irq() and aer_isr() ever both run in kthread context?
Am I missing something?

> at the same FIFO priority.  This can lead to the aer_isr thread starving
> the aer_irq thread, particularly if multi_error_valid causes a scan of
> all devices, and multiple errors are raised during the scan.

I'm not seeing aer_isr() waiting on a spinlock, so how can it be starved?

Thanks,

Lukas