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Date:   Fri, 15 Mar 2019 12:50:02 +0100
From:   Dominik Brodowski <linux@dominikbrodowski.net>
To:     David Howells <dhowells@redhat.com>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Tejun Heo <tj@kernel.org>, Li Zefan <lizefan@huawei.com>,
        Johannes Weiner <hannes@cmpxchg.org>, cgroups@vger.kernel.org,
        fenghua.yu@intel.com, linux-kernel@vger.kernel.org
Subject: Re: fs_context-related oops in mainline
Message-ID: <20190315115002.GA9055@light.dominikbrodowski.net>
References: <20190315074307.GA31430@light.dominikbrodowski.net>
 <3476.1552650285@warthog.procyon.org.uk>
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On Fri, Mar 15, 2019 at 11:44:45AM +0000, David Howells wrote:
> Dominik Brodowski <linux@dominikbrodowski.net> wrote:
> 
> > [    0.839322] RIP: 0010:sysfs_init_fs_context+0x82/0xd0
> 
> Could you load your kernel into gdb and then do:
> 
> 	i li *sysfs_init_fs_context+0x82

Doesn't seem necessary as per my mail to Al a few seconds ago:
kobj_ns_grab_current(KOBJ_NS_TYPE_NET) returns NULL, so

        fc->user_ns = get_user_ns(netns->user_ns);

will try to dereference a null pointer.

Thanks,
	Dominik