Re: 2.6.23-rc1-mm1: boot hang on ia64 with memoryless nodes

Christoph Lameter
2007-07-25T19:38:26Z

(ccing Andy who did the work on the config stuff)

On Wed, 25 Jul 2007, Lee Schermerhorn wrote:

> I tried to deselect SPARSEMEM_VMEMMAP. Kconfig's "def_bool=y" wouldn't
> let me :-(. After hacking the Kconfig and mm/sparse.c to allow that,
> boot hangs with no error messages shortly after "Built N zonelists..."
> message.

I get a similar hang here and see the system looping in softirq / hrtimer
code.

> Backed off to DISCONTIGMEM+VIRTUAL_MEMORY_MAP, and saw same hang as with
> (SPARSMEM && !SPARSEMEM_VMEMMAP).

So its not related to SPARSE VMEMMAP? General VMEMMAP issue on IA64?

> I should mention that I have my test system in the "fully interleaved"
> configuration for testing the memoryless node patches. This means that
> nodes 0-3 [the real nodes with the cpus attached] have no memory. All
> memory resides in a cpu-less pseudo-node. I'm wondering if
> SPARSEMEM_VMEMMAP can handle this? 22-rc6-mm1 booted OK on this config
> w/ SPARSEMEM_EXTREME.

The vmemmap page table blocks get allocated on the nodes where there
is actual mmemory but sparse.c may not have been updated to only look for
memory on nodes that have memory. If it looks for online nodes then we
may have an issue there. Andy?

Were you able to run discontig/vmemmap in the past with this
configuration?