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

From: Stephane Eranian
Date: Tue Jun 16 2015 - 03:03:33 EST


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?
Thanks.
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