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Re: sm 56





guy keren wrote:

> On Sun, 30 Sep 2001, Gilad Ben-Yossef wrote:
> 
> 
>> Lack of source is a problem.
>> Try to
> 
> [... large complex idea deleted]
> 
> why go so far? if you insmod a module that tries using kernel functions
> whose signatures have changed, you will get an 'unresolved symbol' error
> message for each such changed/missing function.

You are right of course.
But I didn't understood from the guy that he got an insmod error of 
unresolved symbols, but rather some module specific error (something 
about bad characters if my memory serves).

What I meant was that although the specific function interface may not 
have changed (and this is what AFAIK the signature checks, not the 
implmentation), the inwards bits of the functions changed, or even other 
functions they use which caused the problem.

Yes, it's far fetched, but possible. Sometime someone fixes a bug in the 
kernel code that the binary only module relies on to work. In one 
example I saw a code that used a fixed amount of "jiffies" to calculate 
time instead of relaying on the value of HZ and the driver code relied 
on the bad use. When the kernel was fixed, the driver had to be changed. 
We didn't have the source, but it was easy to edit the binary to change 
the multiplier used in the driver and it solved the problem, once we 
figured out what going on and then a similar debug technique helped.

Gilad.



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