I just saw this when booting a current linux-2.6.git kernel (3fe0344faf7fdcb158bd5c1a9aec960a8d70c8e8).
.config and full bootlog attached.

BUG: sleeping function called from invalid context at /home/jeremy/git/linux/mm/slab.c:3029
in_atomic(): 1, irqs_disabled(): 0, pid: 388, name: lvm
Pid: 388, comm: lvm Not tainted 2.6.30 #225
Call Trace:
 [<ffffffff81137a65>] ? __init_rwsem+0x29/0x39
 [<ffffffff81035346>] __might_sleep+0x110/0x112
 [<ffffffff810acf07>] kmem_cache_alloc+0x38/0x12b
 [<ffffffff810a71d4>] ? mempool_alloc_pages_isa+0x0/0x10
 [<ffffffff8108a5df>] mempool_create_node+0x2f/0x152
 [<ffffffff8108a31c>] ? mempool_free_pages+0x0/0xb
 [<ffffffff8108a70f>] mempool_create+0xd/0xf
 [<ffffffff810a71ad>] init_emergency_isa_pool+0x28/0x4f
 [<ffffffff81127b90>] blk_queue_bounce_limit+0x40/0x56
 [<ffffffffa00f856c>] dm_table_set_restrictions+0x82/0xa6 [dm_mod]
 [<ffffffffa00f6415>] dm_swap_table+0x132/0x15a [dm_mod]
 [<ffffffffa00faf61>] dev_suspend+0xfd/0x177 [dm_mod]
 [<ffffffffa00fb959>] dm_ctl_ioctl+0x252/0x2a2 [dm_mod]
 [<ffffffffa00fae64>] ? dev_suspend+0x0/0x177 [dm_mod]
 [<ffffffff810bd4c0>] vfs_ioctl+0x2a/0x77
 [<ffffffff810bd9b4>] do_vfs_ioctl+0x4a7/0x4fa
 [<ffffffff810bda5e>] sys_ioctl+0x57/0x7a
 [<ffffffff81011042>] system_call_fastpath+0x16/0x1b

	J