Re: NULL pointer at kset_find_obj

[CAI Qian <caiqian@redhat.com>]

----- Original Message -----
> From: "David Howells" <dhowells@redhat.com>
> To: "CAI Qian" <caiqian@redhat.com>, rusty@rustcorp.com.au
> Cc: dhowells@redhat.com, "LKML" <linux-kernel@vger.kernel.org>
> Sent: Wednesday, April 3, 2013 1:38:50 AM
> Subject: Re: NULL pointer at kset_find_obj
> 
> CAI Qian <caiqian@redhat.com> wrote:
> 
> > Just booted the latest mainline,
> > 
> > [   35.217698] Request for unknown module key 'Magrathea: Glacier signing
> > key: 8b7774b08bc4ee9637073434c10f0823f6fbe523' err -11
> 
> Can you check back earlier in the dmesg to see whether the kernel tried to
> load the key?  -11 is presumably -EAGAIN - in which case no such key was
> found
> (rather than there being a cached lookup failure which is what -ENOKEY would
> indicate).  It is possible that you encountered the key-not-yet-valid problem
> due to your h/w clock showing a value prior to the start date on the key.
Hmm, unsure about how to check it, but here is the full log prior the panic,
http://people.redhat.com/qcai/stable/log.key

CAI Qian
>  
> > [   35.218511] BUG: unable to handle kernel paging request at
> > ffffffffa03093f0
> > [   35.218521] IP: [<ffffffff81304710>] kset_find_obj+0x30/0x80
> > ...
> > [   35.218575] Call Trace:
> > [   35.218583]  [<ffffffff810c827d>] load_module+0xb0d/0x1b00
> > [   35.218587]  [<ffffffff81321880>] ? ddebug_proc_open+0xc0/0xc0
> > [   35.218593]  [<ffffffff81628cd8>] ? page_fault+0x28/0x30
> > [   35.218596]  [<ffffffff810c9347>] sys_init_module+0xd7/0x120
> > [   35.218601]  [<ffffffff81630d59>] system_call_fastpath+0x16/0x1b
> 
> I think this bit should be waved in front of Rusty.  It looks like it might
> be
> a bug in error handling code.
> 
> David
>