Re: [PATCH] perf symbols: Fix annotation of objects with debuginfo files

[Naveen N. Rao]

On 2016/08/12 04:35PM, Anton Blanchard wrote:
> From: Anton Blanchard <anton@xxxxxxxxx>
> 
> Commit 73cdf0c6ea9c ("perf symbols: Record text offset in dso
> to calculate objdump address") started storing the offset of
> the text section for all DSOs: 
> 
>        if (elf_section_by_name(elf, &ehdr, &tshdr, ".text", NULL))
>                dso->text_offset = tshdr.sh_addr - tshdr.sh_offset;
> 
> Unfortunately this breaks debuginfo files, because we need to calculate
> the offset of the text section in the associated executable file. As a
> result perf annotate returns junk for all debuginfo files.

I am able to reproduce this.

> 
> Fix this by using runtime_ss->elf which should point at the executable
> when parsing a debuginfo file.
> 
> Cc: stable@xxxxxxxxxxxxxxx # v4.6+
> Fixes: 73cdf0c6ea9c ("perf symbols: Record text offset in dso to calculate objdump address")
> Signed-off-by: Anton Blanchard <anton@xxxxxxxxx>
> ---
> 
> diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> index a34321e..9e36073 100644
> --- a/tools/perf/util/symbol-elf.c
> +++ b/tools/perf/util/symbol-elf.c
> @@ -837,7 +837,7 @@ int dso__load_sym(struct dso *dso, struct map *map,
>  	sec = syms_ss->symtab;
>  	shdr = syms_ss->symshdr;
> 
> -	if (elf_section_by_name(elf, &ehdr, &tshdr, ".text", NULL))
> +	if (elf_section_by_name(runtime_ss->elf, &ehdr, &tshdr, ".text", NULL))
                                                 ^^^^^
I suppose you missed updating ehdr to runtime_ss->ehdr?
With that change, perf annotate works for me.

- Naveen