On Sun, 20 Feb 2005, Max Laier wrote: > Joerg Sonnenberger has discovered a problem in the snc(4) driver that > might result in packets showing up on bpf multiple times. See the > changelog for sys/dev/netif/snc/dp83932.c in their source tree[1]. > > Attached is a fix for HEAD. I am almost sure that it is right, but I'd > welcome a review as there might be a chance that sonicput() and the TX > interrupt free the mbuf before it gets to bpf. From my reading it seems > that the mbuf is "safe" until sc->mtd_free is altered (see comment).
This change seems fine -- in the current world order, Giant will prevent the driver from preempting itself and freeing the mbuf, and if we get per-softc locking for snc, presumably that locking will provide the same protection. It may be worth annotating that we rely on non-preemption by the interrupt handler to avoid the mbuf being freed with a comment. Robert N M Watson _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
