[lttng-dev] lttng kretprobe issue

[tarek.slaymia@gmail.com (tarek slaymia)]

Hi all

when i replace a syscall function address for example sys_write using this
function in my LKM module :

xchg(&sys_call_table[__NR_write],my_own_write);

In the normal case the content of sys_call_table[__NR_write] address
changes and it displays the address of my_own_write using debug technique .

I have an issue when tracing this change using lttng kretprobe :

lttng enable-event sys_write -k --function sys_write

 The ip value of sys_write ( the same address of sys_call_table[__NR_write]
) remains the same even after changing it by the new function address
(address of my_own_write)
Why the ip value of sys_write syscall displayed in lttng traces remains the
same even after changing it ?

Best regards.
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