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From: Joe Buehler <aspam@cox.net>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: netdev@vger.kernel.org, David Daney <ddaney@caviumnetworks.com>
Subject: Re: kernel panic in fib_rules_lookup [2.6.27.7 vendor-patched]
Date: Sat, 23 Oct 2010 11:40:35 -0400	[thread overview]
Message-ID: <4CC301F3.5010504@cox.net> (raw)
In-Reply-To: <1287847465.2658.266.camel@edumazet-laptop>

Eric Dumazet wrote:
>
> David Daney added a nudge_writes(), actually doing a "syncw"
> instruction, and this seems to be the smp_wmb() this platform should be
> using in the first place, not a pure compiler barrier (barrier()) 
>
> So Joe, you might want to change the smp_wmb() call in
> rcu_assign_pointer() by the nudge_writes() call, and see what happens...
>
>
>   

I think Daney is Cavium's Octeon LINUX guru from the posts I've seen so
he would definitely know the platform.  I'm not sure I quite understand
what you are saying but it sounds as though you are saying that smp_wb
is not doing a syncw and that sounds *totally* broken -- snycw is what
the low-level Cavium SDK uses for memory barriers all over the place.

Joe Buehler


  reply	other threads:[~2010-10-23 15:40 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-10-12 17:14 kernel panic in fib_rules_lookup [2.6.27.7 vendor-patched] Joe Buehler
2010-10-12 17:40 ` Eric Dumazet
2010-10-13 11:18   ` Joe Buehler
2010-10-20 17:43   ` Joe Buehler
2010-10-20 22:05     ` Eric Dumazet
2010-10-22 20:30       ` Joe Buehler
2010-10-23  3:44         ` Eric Dumazet
2010-10-23 15:11           ` Eric Dumazet
2010-10-23 15:24             ` Eric Dumazet
2010-10-23 15:40               ` Joe Buehler [this message]
2010-10-23 16:07                 ` Eric Dumazet
2010-10-23 15:33             ` Joe Buehler
2010-10-23 16:35               ` Eric Dumazet
2010-10-23 17:37                 ` "Oleg A. Arkhangelsky"
2010-10-23 19:44                   ` Eric Dumazet
2010-10-26 18:43                     ` David Miller
2010-10-26 13:29                 ` Joe Buehler
2010-10-26 13:36                   ` Eric Dumazet
2010-10-26 13:53                     ` Joe Buehler
2010-10-26 13:58                       ` Eric Dumazet
2010-10-26 14:33                       ` Eric Dumazet
2010-10-26 14:41                         ` Joe Buehler
2010-10-27 21:01                         ` Joe Buehler
2010-10-27 21:05                           ` Eric Dumazet
2010-12-02 13:36                             ` Joe Buehler
2010-12-02 14:04                               ` Eric Dumazet

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