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User-Agent: Mozilla/5.0 (compatible; Konqueror/3.2; Linux) (KHTML, like Gecko)

Description of problem:
After rebuilding kernel, turning on preempt (no other changes to standard fedora config):
Debug: sleeping function called from invalid context at mm/slab.c:1856
Feb 11 19:47:54 localhost kernel: in_atomic():1, irqs_disabled():0
Feb 11 19:47:54 localhost kernel: Call Trace:
Feb 11 19:47:54 localhost kernel:  [<c012776c>] __might_sleep+0xac/0xe0
Feb 11 19:47:54 localhost kernel:  [<c015ac94>] kmem_cache_alloc+0x194/0x1a0
Feb 11 19:47:54 localhost kernel:  [<c018b13f>] cdev_alloc+0x1f/0x60
Feb 11 19:47:54 localhost kernel:  [<e091a75a>] st_probe+0x3ba/0x790 [st]
Feb 11 19:47:54 localhost kernel:  [<c019ce4c>] dput+0x1c/0x710
Feb 11 19:47:54 localhost kernel:  [<c01d71c5>] create_dir+0xb5/0xc0
Feb 11 19:47:54 localhost kernel:  [<c01d7222>] sysfs_create_dir+0x32/0x70
Feb 11 19:47:54 localhost kernel:  [<c0266302>] bus_match+0x32/0x60
Feb 11 19:47:55 localhost kernel:  [<c0266429>] driver_attach+0x59/0x90
Feb 11 19:47:55 localhost kernel:  [<c0204e82>] kobject_register+0x22/0x60
Feb 11 19:47:55 localhost kernel:  [<c02666e1>] bus_add_driver+0x91/0xb0
Feb 11 19:47:55 localhost cups: cupsd startup succeeded
Feb 11 19:47:55 localhost kernel:  [<c0266b00>] driver_register+0x80/0x90
Feb 11 19:47:55 localhost kernel:  [<e08ad051>] init_st+0x51/0x8f [st]
Feb 11 19:47:55 localhost kernel:  [<c014b8c6>] sys_init_module+0x1c6/0x390
Feb 11 19:47:55 localhost kernel:  [<c010c69b>] syscall_call+0x7/0xb
Feb 11 19:47:56 localhost kernel: 

Version-Release number of selected component (if applicable):
2.6.1-1.65custom

How reproducible:
Didn't try

Steps to Reproduce:
1.boot
2.
3.
    

Additional info: