From: Arnaldo Carvalho de Melo <acme@redhat.com>
To: Stephane Eranian <eranian@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Jiri Olsa <jolsa@redhat.com>,
Namhyung Kim <namhyung@kernel.org>,
David Ahern <dsahern@gmail.com>,
Peter Zijlstra <peterz@infradead.org>,
"mingo@elte.hu" <mingo@elte.hu>
Subject: Re: [BUG] perf report: fails to symbolize when vaddr is non zero for shared objects
Date: Tue, 16 Jun 2015 11:34:01 -0300 [thread overview]
Message-ID: <20150616143401.GA2548@redhat.com> (raw)
In-Reply-To: <CABPqkBTPruhg+B3N899vEJtAsd8ihDs+oMjOB_C8Xs=ZZE-FDQ@mail.gmail.com>
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
next prev parent reply other threads:[~2015-06-16 14:34 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-16 7:03 [BUG] perf report: fails to symbolize when vaddr is non zero for shared objects Stephane Eranian
2015-06-16 14:34 ` Arnaldo Carvalho de Melo [this message]
2015-06-17 18:54 ` Stephane Eranian
2015-06-17 19:24 ` Arnaldo Carvalho de Melo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20150616143401.GA2548@redhat.com \
--to=acme@redhat.com \
--cc=dsahern@gmail.com \
--cc=eranian@google.com \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.