[Crash-utility] Crash issue when loading vmcore

[Dave Anderson]

----- "Paul-Kenji Cahier Furuya" <pkc at f1-photo.com> wrote:

> On 08/23/2010 22:20, Dave Anderson wrote:
> > Well, yes, you'd have to be able to log into the machine, and
> > then just run:
> >
> >    # crash
> >
> > or if the /vmlinux file is not in a common location, do this:
> >
> >    # crash /path/to/vmlinux
> >
> > And that presumes you've got crash installed on the system as well.
> >
> I might be able to get a physical access at some point, but right now I 
> have none.
> 
> Anything that helps from the logs?

Well, this part is still unexplainable -- in the crashd8.txt, the symbol
addresses that were seen by the crashed kernel are as shown:
 
# grep SYMBOL crashd8.txt
                         SYMBOL(init_uts_ns)=c06f9120
                         SYMBOL(node_online_map)=c0730644
                         SYMBOL(swapper_pg_dir)=c06e4000
                         SYMBOL(_stext)=c0101000
                         SYMBOL(vmlist)=c07d3540
                         SYMBOL(mem_map)=c07d3500
                         SYMBOL(contig_page_data)=c072ce80
                         SYMBOL(log_buf)=c06fc83c
                         SYMBOL(log_end)=c07bb7ec
                         SYMBOL(log_buf_len)=c06fc838
                         SYMBOL(logged_chars)=c07c38a0
#

But the "sym.l" list starts with a unity-mapped PAGE_OFFSET
value of c1000000 (instead of the more common c0000000) 

  c1000000 (T) _text
  c1000000 (T) startup_32
  c1000054 (t) default_entry
  c1001000 (T) _stext
  c1001010 (T) do_one_initcall
  c1001180 (t) init_post
  c10012c0 (T) name_to_dev_t
  c1001500 (T) thread_saved_pc
  c1001510 (T) prepare_to_copy
  c1001590 (T) get_wchan
  c1001640 (T) __switch_to
  ...

So that being the case, the symbol values for "init_uts_ns", "node_online_map",
and so on, don't even match those of the crashed kernel:

  c1662120 (D) init_uts_ns
  c1716000 (B) swapper_pg_dir
  c1001000 (T) _stext
  c173ed3c (B) vmlist
  c173ed00 (B) mem_map
  c1696180 (D) contig_page_data
  c17248a0 (b) __log_buf
  c17247ec (b) log_end
  c16656b8 (d) log_buf_len
  c172c8a0 (b) logged_chars

So that doesn't make any sense unless the vmlinux file and the vmlinux that
was running on the crashed kernel are not the same kernels.  Are you using
a different kernel as the secondary kdump kernel?

Dave






node_online_map doesn't even exist in your sym.l file.