From: Evgeniy Polyakov <zbr@ioremap•net>
To: Eric Dumazet <dada1@cosmosbay•com>
Cc: Stephen Hemminger <shemminger@vyatta•com>,
Herbert Xu <herbert@gondor•apana.org.au>,
berrange@redhat•com, et-mgmt-tools@redhat•com,
davem@davemloft•net, netdev@vger•kernel.org
Subject: Re: virt-manager broken by bind(0) in net-next.
Date: Sat, 31 Jan 2009 00:50:08 +0300 [thread overview]
Message-ID: <20090130215008.GB12210@ioremap.net> (raw)
In-Reply-To: <498349F7.4050300@cosmosbay.com>
On Fri, Jan 30, 2009 at 07:41:59PM +0100, Eric Dumazet (dada1@cosmosbay•com) wrote:
> Reviewing commit a9d8f9110d7e953c2f2b521087a4179677843c2a
>
> I see use of a hashinfo->bsockets field that :
>
> - lacks proper lock/synchronization
It should contain rough number of sockets, there is no need to be very
precise because of this hueristic.
> - suffers from cache line ping pongs on SMP
I used free alignment slot so that socket structure would not be
icreased.
> Also there might be a problem at line 175
>
> if (sk->sk_reuse && sk->sk_state != TCP_LISTEN && --attempts >= 0) {
> spin_unlock(&head->lock);
> goto again;
>
> If we entered inet_csk_get_port() with a non null snum, we can "goto again"
> while it was not expected.
>
> diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
> index df8e72f..752c6b2 100644
> --- a/net/ipv4/inet_connection_sock.c
> +++ b/net/ipv4/inet_connection_sock.c
> @@ -172,7 +172,8 @@ tb_found:
> } else {
> ret = 1;
> if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
> - if (sk->sk_reuse && sk->sk_state != TCP_LISTEN && --attempts >= 0) {
> + if (sk->sk_reuse && sk->sk_state != TCP_LISTEN &&
> + smallest_size == -1 && --attempts >= 0) {
I think it should be smallest_size != -1, since we really want to goto
to the again label when hueristic is used, which in turn changes
smallest_size.
--
Evgeniy Polyakov
next prev parent reply other threads:[~2009-01-30 21:50 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20090128212114.38be3e8c@extreme>
[not found] ` <20090129103544.GC22110@redhat.com>
2009-01-30 5:35 ` virt-manager broken by bind(0) in net-next Stephen Hemminger
2009-01-30 8:16 ` Evgeniy Polyakov
[not found] ` <20090130081600.GA2717-i6C2adt8DTjR7s880joybQ@public.gmane.org>
2009-01-30 10:27 ` Daniel P. Berrange
2009-01-30 11:21 ` Evgeniy Polyakov
2009-01-30 12:53 ` Herbert Xu
[not found] ` <20090130125337.GA7155-lOAM2aK0SrRLBo1qDEOMRrpzq4S04n8Q@public.gmane.org>
2009-01-30 17:57 ` Stephen Hemminger
2009-01-30 18:41 ` Eric Dumazet
2009-01-30 21:50 ` Evgeniy Polyakov [this message]
2009-01-30 22:30 ` Eric Dumazet
2009-01-30 22:51 ` Evgeniy Polyakov
[not found] ` <20090130225113.GA13977-i6C2adt8DTjR7s880joybQ@public.gmane.org>
2009-01-31 0:36 ` Stephen Hemminger
2009-01-31 8:35 ` Evgeniy Polyakov
2009-01-31 2:52 ` Stephen Hemminger
2009-01-31 8:37 ` Evgeniy Polyakov
2009-01-31 9:17 ` Eric Dumazet
2009-01-31 9:31 ` Evgeniy Polyakov
2009-01-31 9:49 ` Eric Dumazet
2009-01-31 9:56 ` Evgeniy Polyakov
2009-01-31 10:17 ` Eric Dumazet
2009-02-01 12:42 ` Evgeniy Polyakov
2009-02-01 16:12 ` Eric Dumazet
2009-02-01 17:40 ` Evgeniy Polyakov
2009-02-01 20:31 ` David Miller
[not found] ` <20090130215008.GB12210-i6C2adt8DTjR7s880joybQ@public.gmane.org>
2009-02-01 5:58 ` Stephen Hemminger
2009-02-01 9:07 ` David Miller
2009-02-01 12:44 ` Evgeniy Polyakov
[not found] ` <498349F7.4050300-fPLkHRcR87vqlBn2x/YWAg@public.gmane.org>
2009-02-01 5:29 ` Stephen Hemminger
2009-01-30 6:50 ` Stephen Hemminger
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090130215008.GB12210@ioremap.net \
--to=zbr@ioremap$(echo .)net \
--cc=berrange@redhat$(echo .)com \
--cc=dada1@cosmosbay$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=et-mgmt-tools@redhat$(echo .)com \
--cc=herbert@gondor$(echo .)apana.org.au \
--cc=netdev@vger$(echo .)kernel.org \
--cc=shemminger@vyatta$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox