Kernel crash when using systemtap

[Padmanabhan S N <paddusn at yahoo dot com>]

While using systemtap to do function call tracing (.call, .inline. .return probes) on one of our proprietary kernel modules, the system crashes. The function call tracing however works perfectly fine on kernel functions and other modules (for ex. ext3, nfsd, etc.).


I've tried downgrading (to versions as low as 0.8) and upgrading to the latest version, but that doesnt help. I've even tried blacklisting some of our module functions, but that doesnt work either. 

Any pointers ??


The environment is RHEL 5.5 64-bit. I've tried to look at the crash 
dump, and it does point to the generated systemtap module. But I 
couldn't proceed beyond that. Here is a bt from one of the crash dumps. 

?#0 [ffff8100956f17a0] crash_kexec at ffffffff800aeb6b
?#1 [ffff8100956f1860] __die at ffffffff80066157
?#2 [ffff8100956f18a0] do_page_fault at ffffffff80067dd7
?#3 [ffff8100956f1990] error_exit at ffffffff8005ede9
?#4 [ffff8100956f1af0] add_to_page_cache at ffffffff8000c722
?#5 [ffff8100956f1b48] _stp_map_get_ii at ffffffff889d8459 [stap_44a2f6019f0e29a88c9470c55950ae1a_14041197]
?#6 [ffff8100956f1c20] __generic_file_aio_read at ffffffff8000c5a8
?#7 [ffff8100956f1c90] generic_file_aio_read at ffffffff80016dd4
?#8 [ffff8100956f1e10] kretprobe_trampoline_holder at ffffffff80066b82
?#9 [ffff8100956f1f10] vfs_read at ffffffff8000b6b0
#10 [ffff8100956f1f40] sys_read at ffffffff80011c01


Thanks,
Padhu.