From: Stephen Hemminger <shemminger@vyatta•com>
To: Eric Dumazet <eric.dumazet@gmail•com>
Cc: Paul Moore <pmoore@redhat•com>, Jason Wang <jasowang@redhat•com>,
netdev@vger•kernel.org
Subject: Re: TUN problems (regression?)
Date: Thu, 20 Dec 2012 15:50:01 -0800 [thread overview]
Message-ID: <20121220155001.538bbdb0@nehalam.linuxnetplumber.net> (raw)
In-Reply-To: <1356046697.21834.3606.camel@edumazet-glaptop>
On Thu, 20 Dec 2012 15:38:17 -0800
Eric Dumazet <eric.dumazet@gmail•com> wrote:
> On Thu, 2012-12-20 at 18:16 -0500, Paul Moore wrote:
> > [CC'ing netdev in case this is a known problem I just missed ...]
> >
> > Hi Jason,
> >
> > I started doing some more testing with the multiqueue TUN changes and I ran
> > into a problem when running tunctl: running it once w/o arguments works as
> > expected, but running it a second time results in failure and a
> > kmem_cache_sanity_check() failure. The problem appears to be very repeatable
> > on my test VM and happens independent of the LSM/SELinux fixup patches.
> >
> > Have you seen this before?
> >
>
> Obviously code in tun_flow_init() is wrong...
>
> static int tun_flow_init(struct tun_struct *tun)
> {
> int i;
>
> tun->flow_cache = kmem_cache_create("tun_flow_cache",
> sizeof(struct tun_flow_entry), 0, 0,
> NULL);
> if (!tun->flow_cache)
> return -ENOMEM;
> ...
> }
>
>
> I have no idea why we would need a kmem_cache per tun_struct,
> and why we even need a kmem_cache.
Normally flow malloc/free should be good enough.
It might make sense to use private kmem_cache if doing hlist_nulls.
Acked-by: Stephen Hemminger <shemminger@vyatta•com>
next prev parent reply other threads:[~2012-12-20 23:51 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-20 23:16 TUN problems (regression?) Paul Moore
2012-12-20 23:38 ` Eric Dumazet
2012-12-20 23:50 ` Stephen Hemminger [this message]
2012-12-21 3:32 ` Jason Wang
2012-12-21 3:39 ` Eric Dumazet
2012-12-21 4:26 ` Jason Wang
2012-12-28 0:41 ` Stephen Hemminger
2012-12-28 5:43 ` Jason Wang
2012-12-28 6:25 ` Stephen Hemminger
2013-01-04 5:04 ` Jason Wang
2012-12-21 21:15 ` David Miller
2012-12-21 16:27 ` Paul Moore
2012-12-21 17:17 ` [PATCH] tuntap: dont use a private kmem_cache Eric Dumazet
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