Re: Regression in 2.6.23-rc2-mm2, mounting cpusets causes a hang

Serge E. Hallyn
2007-08-14T18:04:19Z

Quoting Lee Schermerhorn (Lee.Schermerhorn@hp.com):
> On Mon, 2007-08-13 at 15:12 -0500, Serge E. Hallyn wrote:
> > Quoting Dhaval Giani (dhaval@linux.vnet.ibm.com):
> > > Hi,
> > >
> > > On mounting cpusets using containers, I have been hitting the following
> > > bug.
> > >
> > >
> > > -----------[ cut here ]------------
> > > kernel BUG at kernel/cpuset.c:331!
> <snip>
> > > CONFIG_HIGHMEM=y
> > > CONFIG_X86_PAE=y
> > > # CONFIG_NUMA is not set
> > > CONFIG_ARCH_POPULATES_NODE_MAP=y
> > > CONFIG_SELECT_MEMORY_MODEL=y
> > > CONFIG_FLATMEM_MANUAL=y
> > > # CONFIG_DISCONTIGMEM_MANUAL is not set
> > > # CONFIG_SPARSEMEM_MANUAL is not set
> > > CONFIG_FLATMEM=y
> > > CONFIG_FLAT_NODE_MEM_MAP=y
> > > # CONFIG_SPARSEMEM_STATIC is not set
> > > CONFIG_SPLIT_PTLOCK_CPUS=4
> > > CONFIG_RESOURCES_64BIT=y
> > > CONFIG_ZONE_DMA_FLAG=1
> <snip>
> >
> > Yeah, I'm seeing the same thing. Oddly, my node_states[N_NORMAL_MEMORY]
> > and node_states[N_HIGH_MEMORY] are empty, while node_states[N_ONLINE]
> > contains my single cpu (on i386 kvm image).
> >
> > -serge
>
> Yes, you'll definitely hit that BUG if the N_HIGH_MEMORY mask is empty.
> So far, I can't see how this could be, tho'. __build_all_zonelists()
> should be called for non-NUMA as well as NUMA. It iterates over "all

Yup, and it is, and some debug statements insist that
node_set_state(nid, N_HIGH_MEMORY) is being called for cpu 0,
and the state is in fact being correctly set.

So it must get cleared later...

-serge