netdev - Re: [PATCH 2/4] virtio_net: return NETDEV_TX_BUSY instead of queueing an extra skb.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sun, 14 Jun 2009 16:45:28 +1000
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	Rusty Russell <rusty@...tcorp.com.au>
Cc:	netdev@...r.kernel.org, virtualization@...ts.linux-foundation.org,
	David Miller <davem@...emloft.net>
Subject: Re: [PATCH 2/4] virtio_net: return NETDEV_TX_BUSY instead of
	queueing an extra skb.

On Sat, Jun 13, 2009 at 10:00:37PM +0930, Rusty Russell wrote:
> 
> But re your comment that the 67 drivers using TX_BUSY are doing it because of 
> driver bugs, that's hard to believe.  It either hardly ever happens (in which 
> case just drop the packet), or it happens (in which case we should handle it 
> correctly).

Most of them just do this:

start_xmit:

if (unlikely(queue is full)) {
	/* This should never happen. */
	return TX_BUSY;
}

transmit

if (queue is full)
	stop queue

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html