Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933651AbaJUVMb (ORCPT ); Tue, 21 Oct 2014 17:12:31 -0400 Received: from scrye.com ([75.148.32.185]:42236 "EHLO mail.scrye.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932998AbaJUVM3 (ORCPT ); Tue, 21 Oct 2014 17:12:29 -0400 X-Greylist: delayed 89464 seconds by postgrey-1.27 at vger.kernel.org; Tue, 21 Oct 2014 17:12:29 EDT Date: Tue, 21 Oct 2014 15:12:25 -0600 From: Kevin Fenzi To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: localed stuck in recent 3.18 git in copy_net_ns? Message-ID: <20141021151225.5df96645@voldemort.scrye.com> In-Reply-To: <20141020145359.565fe5e6@voldemort.scrye.com> References: <20141020141515.0688bf33@voldemort.scrye.com> <20141020204326.GA25668@redhat.com> <20141020145359.565fe5e6@voldemort.scrye.com> Organization: Scrye, INC X-Mailer: Claws Mail 3.10.1 (GTK+ 2.24.25; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; boundary="Sig_/8EpoeABSFT5aSPRhbEEQiaj"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/8EpoeABSFT5aSPRhbEEQiaj Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 20 Oct 2014 14:53:59 -0600 Kevin Fenzi wrote: > On Mon, 20 Oct 2014 16:43:26 -0400 > Dave Jones wrote: >=20 > > I've seen similar soft lockup traces from the sys_unshare path when > > running my fuzz tester. It seems that if you create enough network > > namespaces, it can take a huge amount of time for them to be > > iterated. (Running trinity with '-c unshare' you can see the slow > > down happen. In some cases, it takes so long that the watchdog > > process kills it -- though the SIGKILL won't get delivered until > > the unshare() completes) > >=20 > > Any idea what this machine had been doing prior to this that may > > have involved creating lots of namespaces ? >=20 > That was right after boot. ;)=20 >=20 > This is my main rawhide running laptop. >=20 > A 'ip netns list' shows nothing. Some more information:=20 The problem started between:=20 v3.17-7872-g5ff0b9e1a1da and v3.17-8307-gf1d0d14120a8 (I can try and do a bisect, but have to head out on a trip tomorrow) In all the kernels with the problem, there is a kworker process in D.=20 sysrq-t says:=20 Showing all locks held in the s= ystem: Oct 21 15:06:31 voldemort.scrye.com kernel: 4 locks held by kworker/u16:0/6: Oct 21 15:06:31 voldemort.scrye.com kernel: #0: ("%s""netns"){.+.+.+}, at= : [] process_one_work+0x17f/0x850 Oct 21 15:06:31 voldemort.scrye.com kernel: #1: (net_cleanup_work){+.+.+.= }, at: [] process_one_work+0x17f/0x850 Oct 21 15:06:31 voldemort.scrye.com kernel: #2: (net_mutex){+.+.+.}, at: = [] cleanup_net+0x8c/0x1f0 Oct 21 15:06:31 voldemort.scrye.com kernel: #3: (rcu_sched_state.barrier_mutex){+.+...}, at: [] _rcu_barrier+0x35/0x200 On first running any of the systemd units that use PrivateNetwork, then run ok, but they are also set to timeout after a minute. On sucessive runs they hang in D also. kevin --Sig_/8EpoeABSFT5aSPRhbEEQiaj Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCgAGBQJURsw8AAoJEEs3sNgP+7te26UQALzAA3CzNnsuGPbEcKl96MYi fU/INHD/fr1WL5cHQDVfUvhCQsdTNve3fgNxrlhoBSbTEgLFvoAnc0uyM9VKloYR TSXfVk7Uwo1BW0Y9Pi0Ezp23O2yRaUyPLpO0T/tk58E+wAb7aKENr+vRykfxJsQ8 5g1hesLMlCb7Qwd7Es1/zdk3FSnXb+9VhP7WrOdktJnM4KmtP9YSM0O13MLtVOM0 fjPDYOf2RpqLSX+UC7uOzDsACTuSBjOoilFQ34mx33Mm/3hgmyGI6LBTDt5B1Av3 tAGYDSqS7WExy1wD2r+DwZpZBs9xGb8yA7I2iLLJJcu+fjL8PBcqWuf6AL/oxFGu XXfLFCqryM2R4yURLSvBdX07lieLs8DsMwr9Qp91yMwc48VLKuDj8o7Qz0XZ5tUn +zJooaoIRY5IcNff9jQmwD27XfiObhkMNaoyFYHVhZeeAtNuXDx8XfUzEWfIU8eq FWluQzcDt/HZdavrf5YbtxD07SPIOw1jPWT+2DFwU5I0jAiqQw8/SEqn835B8NhI /d0Tqqf3dREkWoFzsrQGwd1L6DC8FH0oDT5f4wJwT9HkpWZRAzTdJpUgwPPz05t/ M236oJ+sMaXw9f264EKJN68Zyh+Tl8vbTmugExewcJwb7UjeSMJv/ta9+EP8sxLi jw9OTAxtWJOzTrW4dV/b =yqgX -----END PGP SIGNATURE----- --Sig_/8EpoeABSFT5aSPRhbEEQiaj-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/