Hi,

With 4G memory available on the system x machine
  Memory: 3975224k/4980736k available (3764k kernel code, 787208k absent, 218304k reserved, 5318k data, 1272k init)

and by using the attached config file on the kernel versions 2.6.36-rc1 and 2.6.36-rc2
- getting the following panic call trace while running libhugetlbfs autotest

mls21b login: -- 0:conmux-control -- time-stamp -- Aug/21/10 19:52:48 --
-- 0:conmux-control -- time-stamp -- Aug/21/10 20:01:24 --
Kernel panic - not syncing: Out of memory and no killable processes...

Pid: 24576, comm: mmap-cow Not tainted 2.6.36-rc1-git4-autotest #1
Call Trace:
  [<ffffffff813a1906>] panic+0x8c/0x196
  [<ffffffff810da058>] out_of_memory+0x2e8/0x375
  [<ffffffff810de1e6>] __alloc_pages_nodemask+0x556/0x6ac
  [<ffffffff81107717>] alloc_page_vma+0x16d/0x18c
  [<ffffffff810ef661>] do_wp_page+0x384/0x745
  [<ffffffff810ef051>] ? __do_fault+0x412/0x449
  [<ffffffff810f1604>] handle_mm_fault+0x959/0x9c2
  [<ffffffff813a7379>] do_page_fault+0x38e/0x3b2
  [<ffffffff810f7138>] ? do_mmap_pgoff+0x290/0x2f3
  [<ffffffff810f72af>] ? sys_mmap_pgoff+0x114/0x126
  [<ffffffff813a46df>] page_fault+0x1f/0x30
-- 0:conmux-control -- time-stamp -- Aug/21/10 20:03:24 --
-- 0:conmux-control -- time-stamp -- Aug/21/10 20:11:57 --
(bot:conmon-payload) disconnected

Thanks
Divya