cxgbe(4): Do not report link state change during interface detach.
This fixes a panic when multiple VIs are configured on an interface and
only the non-primary VI is up at the time of driver detach. The problem
was that the driver would queue a link state change notification for an
interface about to be freed.
To reproduce the panic, add "hw.cxgbe.num_vis=2" to loader.conf and
- kldload if_cxgbe
- ifconfig vcc0 up
- devctl detach t6nex0
trap 0x9, rip = 0xffffffff8107db70, rsp = 0xfffffe0055263d60, rbp = 0xfffffe0055263dd0 taskqueue_run_locked() at taskqueue_run_locked+0x2a0/frame 0xfffffe0055263dd0 taskqueue_run() at taskqueue_run+0x72/frame 0xfffffe0055263df0 taskqueue_swi_run() at taskqueue_swi_run+0x18/frame 0xfffffe0055263e10 intr_event_execute_handlers() at intr_event_execute_handlers+0x249/frame 0xfffffe0055263e50 ithread_execute_handlers() at ithread_execute_handlers+0x9e/frame 0xfffffe0055263e70
Reviewed by: jhb
MFC after: 1 week
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D45864