[gPXE] interrupt disabling in pxenv_undi_isr()

[Alex Zeffertt]

Hi,

I've noticed in pxe_undi.c that when the NBP calls PXENV_UNDI_ISR:START 
interrupts get disabled.  They are only re-enabled when the NBP calls 
PXENV_UNDI_ISR:GET_NEXT and this returns DONE because there are no more packets.

What happens if a packet is received by the NIC between when 
PXENV_UNDI_ISR:GET_NEXT calls netdev_poll() and when PXENV_UNDI_ISR:GET_NEXT 
returns DONE?

Would the NBP lose the interrupt and not know that it needs to call 
PXENV_UNDI_ISR:START again?

TIA,

Alex