From: Cong Wang <amwang@redhat.com>
To: Debabrata Banerjee <dbavatar@gmail.com>
Cc: netdev@vger.kernel.org, "Banerjee,
Debabrata" <dbanerje@akamai.com>,
"David S. Miller" <davem@davemloft.net>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
Patrick McHardy <kaber@trash.net>
Subject: Re: [PATCH 1/2] ipv6: do not hold route table lock when send ndisc probe
Date: Mon, 20 Aug 2012 20:15:49 +0800 [thread overview]
Message-ID: <1345464949.22373.14.camel@cr0> (raw)
In-Reply-To: <CAATkVEzKuTeUbU75B6EoSfFvGVsz_eK47XNWmsP5KcCvjTDEDA@mail.gmail.com>
On Fri, 2012-08-17 at 14:54 -0400, Debabrata Banerjee wrote:
> Well it get rids of the deadlock for sure, but I am not sure it
> doesn't break something else, one would have to know all of this code
> much better to tell. You'll notice read_unlock_bh(&table->tb6_lock)
> for the first lock in ip6_pol_route() has more in the critical section
> after the rt6_select() call, especially that rather scary BACKTRACK()
> macro.
>
Yeah, I noticed that, ->tb6_lock seems to protect lookup of ->tb6_root,
not sure if 'rt' may still valid after retaking this lock... Hmm,
probably calling ndisc_send_ns() inside a work is a better approach.
I will update the patch.
Thanks!
next prev parent reply other threads:[~2012-08-20 12:16 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-17 7:11 [PATCH 1/2] ipv6: do not hold route table lock when send ndisc probe Cong Wang
2012-08-17 7:11 ` [PATCH 2/2] ipv6: remove some useless RCU read lock Cong Wang
2012-08-17 18:54 ` [PATCH 1/2] ipv6: do not hold route table lock when send ndisc probe Debabrata Banerjee
2012-08-20 12:15 ` Cong Wang [this message]
2012-08-21 3:44 ` Cong Wang
2012-08-22 16:04 ` Banerjee, Debabrata
2012-08-23 9:11 ` Cong Wang
2012-08-23 16:10 ` Eric Dumazet
2012-08-24 9:15 ` Cong Wang
2012-08-24 9:44 ` Eric Dumazet
2012-08-24 10:45 ` Cong Wang
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