On 11-Aug-2003 Ted Unangst wrote: > one more. This falls into the very improbable category. Ordinarily, I > don't think this is possible because FreeBSD doesn't support hotplug PCI, > so sk attachment can't be raced. > > However, assuming I had some hot plug sk card, it seems like running > ifconfig sk0 at just the wrong point during sk1 attach will deadlock. If > it absolutely can not happen (for a reason other than sk is attached > before init runs) please explain. > > sk.c: > sk_attach_xmac() > SK_LOCK(sc); /* grabs */ > ether_ifattach() > ifattach() > IFNET_WLOCK() /* waits for 2 */ > > in6_ifattach.c: > in6_nigroup_attach() > IFNET_RLOCK() /* grabs */ > in6_addmulti() > if_addmulti() > sk_ioctl() > SK_IF_LOCK(); /* waits for 1 */
You can't ifconfig sk0 until after it attaches. sk0 and sk1 don't share locks, so you don't have to worry about the interaction there. Also, SK_LOCK != SK_IF_LOCK, or is that a typo? If it is a typo, then the lock order should still be fixed in some fashion. -- John Baldwin <[EMAIL PROTECTED]> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
