Re: USB: add check to detect host controller hardware removal

[Sebastian Andrzej Siewior <bigeasy@linutronix.de>]

On 2023-10-16 12:56:24 [-0400], Steven Rostedt wrote:
> On Fri, 13 Oct 2023 13:17:52 -0400
> Alan Stern <stern@rowland.harvard.edu> wrote:
> 
> Because in RT, spin_lock()s are actually mutexes.
> 
> In RT, interrupt handlers do not even run with interrupts disabled (they
> run as threads), so the assumption that they run with interrupts disabled
> on RT is incorrect. One hack would simply be:
> 
> 	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
> 		local_irq_disable();
> 	usb_hcd_irq(0, hcd);
> 	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
> 		local_irq_enable();
> 
> But that's rather ugly. We use to have that as a wrapper of just:
> 
> 	local_irq_disable_nort();
> 
> but I don't know if we removed that or not.
> 
> Sebastian?

Got removed once it had zero users. It was hated because it was used
usually used as a quick solution to hide problems underneath.

> -- Steve

Sebastian