re: kern/54495: stopping axe(4) may locks up if NET_MPSAFE is enabled

[matthew green <mrg%eterna.com.au@localhost>]

> The command `ifconfig axe0 down' often locks up on NET_MPSAFE kernel.

skrll added this in rev 1.76, and it comes with this comment:

        /*
         * softnet_lock can be taken when NET_MPAFE is not defined when calling
         * if_addr_init -> if_init.  This doesn't mix well with the
         * usbd_delay_ms calls in the init routines as things like nd6_slowtimo
         * can fire during the wait and attempt to take softnet_lock and then
         * block the softclk thread meaning the wait never ends.
         */
#ifndef NET_MPSAFE
        /* XXX What to reset? */

        /* Wait a little while for the chip to get its brains in order. */
        DELAY(1000);
#else
        axe_ax_init(un);
#endif


i think this is two problems.  (1) the above issue probably
occurs with NET_MPSAFE as well, just less often, and is what
you see here, and (2) we shouldn't reset so completely for
stop, just just disable/turn off stuff.


(fortunately, usbnet appears to be unrelated to this :-)


.mrg.