Need help profiling with Valgrind

Björn Döbel doebel at os.inf.tu-dresden.de
Sun Nov 9 22:54:51 CET 2014


One more hint:

>> The Error message is the following:
>>> L4Re[rm]: unhandled write page fault @7ffff300 pc=15c7a8
>
> This error message tells you that your program is trying to execute an
> instruction at PC value 0x15c7a8. This instruction causes a write page
> fault at address 0x7ffff300 and L4re does not know what to do about it.
>
> This usually happens when you try to access an address with no memory
> mapped. From the address it looks like you are accessing an address
> right below your stack, i.e., you are exceeding L4Re's default stack
> size. Most likely you have a function with a large buffer on the stack
> or you are recursing very deeply?

you might want to use standard binutils (e.g., objdump) on your binary 
to find out what instruction is at the respective PC and map this to 
whatever function it belongs to in your code.

Bjoern



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