[BUG] Kprobes fails on 2.6.25-rc3-mm1 (x86) systems, if CONFIG_DEBUG_RODATA is set.

[Srinivasa DS]

Insertion of kprobe module causes oops on 2.6.25-rc3-mm1 (x86) systems if we 
enable CONFIG_DEBUG_RODATA.  While registering the probe, memcpy() fails to 
copy breakpoint instruction to the instruction address and generates the 
oops.

BUG: unable to handle kernel paging request at ffffffff8047d1a7
IP: [<ffffffff8047ff62>] text_poke+0xa/0x10
PGD 203067 PUD 207063 PMD 7e191163 PTE 47d161
Oops: 0003 [1] PREEMPT SMP
................................................

This is because, Mathieu's patch (http://lkml.org/lkml/2008/2/2/226) makes 
entire text segment as READONLY, if we enable CONFIG_DEBUG_RODATA. 

So reverting this patch or new patch, which considers kprobes while deciding  
boundary for setting readonly pages might solve the probelm.

Thanks
 Srinivasa DS
 LTC-IBM
 



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