Re: [BUG] perf report: fails to symbolize when vaddr is non zero for shared objects

[Arnaldo Carvalho de Melo]

Em Tue, Jun 16, 2015 at 12:03:01AM -0700, Stephane Eranian escreveu:
> Hi,
> 
> It has been brought to my attention that on systems where the text
> of shared libs is not loaded with a zero virtual address, perf report
> fails to symbolize
> correctly samples. This is true of older versions of perf and also the latest
> in tip.git.
> 
> I looked at symbol-elf.c and I did not see a place where the vaddr was taken
> into account from the program headers in the case of ET_DYN. I see it for
> ET_EXE, though.
> 
> $ readelf -e lib.so
>   Type:                              DYN (Shared object file)
>   ....
>   Type          Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
>  LOAD           0x000000 0x0000d000 0x0000d000 0x73657c 0x73657c R E 0x1000
> 
> If you get samples in the shared lib, they will be off, possibly
> attributed to the wrong
> functions.
> 
> Could this be fixed quickly?

You tell me, do you have a patch to propose? :-)

- Arnaldo
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