On 24/06/15 19:17, Will Deacon wrote: > Commit 922d0e4d9f04 ("perf tools: Adjust symbols in VDSO") changed the > ELF symbol parsing so that the vDSO is treated the same as ET_EXEC and > ET_REL binaries despite being an ET_DYN. > > This causes objdump, which expects relative addresses, not to produce > any output in conjunction with perf annotate, which cheerfully passes > absolute addresses when trying to disassemble vDSO functions. > > This patch avoids marking the vDSO as requiring adjustment of symbol > addresses, allowing the relative program counter to be used instead. > > Cc: Vladimir Nikulichev <n...@tbricks.com> > Cc: Adrian Hunter <adrian.hun...@intel.com> > Cc: Namhyung Kim <namhy...@kernel.org> > Reported-by: Kristina Martsenko <kristina.martse...@arm.com> > Signed-off-by: Will Deacon <will.dea...@arm.com> > --- > > Not sure why I've just started seeing this, but it appears to affect > both x86 and arm64. Also, if I revert the patch above then the issue > it supposedly fixed doesn't resurface. Maybe it was just masking another > bug that has since been addressed?
No the problem still appears on older kernels. Probably could look at the vdso section/program headers to decide if it needs adjustment or not. > > tools/perf/util/symbol-elf.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c > index a7ab6063e038..ba4f9bf2765d 100644 > --- a/tools/perf/util/symbol-elf.c > +++ b/tools/perf/util/symbol-elf.c > @@ -706,7 +706,6 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, > const char *name, > GElf_Shdr shdr; > ss->adjust_symbols = (ehdr.e_type == ET_EXEC || > ehdr.e_type == ET_REL || > - dso__is_vdso(dso) || > elf_section_by_name(elf, &ehdr, &shdr, > ".gnu.prelink_undo", > NULL) != NULL); > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/