Re: [BUG] usbip: vhci: Sleeping function called from invalid context in vhci_urb_enqueue on PREEMPT_RT

Alan Stern
2025-08-17T14:27:15Z

On Sat, Aug 16, 2025 at 10:16:34AM -0400, Alan Stern wrote:
> So it looks like we should be using a different function instead of
> local_irq_disable(). We need something which in a non-RT build will
> disable interrupts on the local CPU, but in an RT build will merely
> disable preemption. (In fact, every occurrence of local_irq_disable()
> in the USB subsystem probably should be changed in this way.)

Or maybe what we need is something that in a non-RT build will disable
local interrupts and in an RT build will do nothing. (I suspect that RT
kernels won't like it if we call spin_lock() while preemption is
disabled.)

> Is there such a function?

Alan Stern