On Tue, 12 Jun 2018, Sebastian Andrzej Siewior wrote: > In the code path > __usb_hcd_giveback_urb() > -> wdm_in_callback() > -> service_outstanding_interrupt() > > The function service_outstanding_interrupt() will unconditionally enable > interrupts during unlock and invoke usb_submit_urb() with GFP_KERNEL. > If the HCD completes in BH (like ehci does) then the context remains > atomic due local_bh_disable() and enabling interrupts does not change > this. > > Add an argument to service_outstanding_interrupt() which decides > whether or not it is save to enable interrupts during unlocking and use > GFP_KERNEL or not. Wouldn't it be easier just to use spin_lock_irqsave() and GFP_ATOMIC all the time? That's what people normally do with code that can be called in both process and interrupt contexts. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
