Re: perf not picking up symbols for namespaced processes

From: Jiri Olsa
Date: Tue Feb 04 2020 - 14:27:15 EST


On Tue, Feb 04, 2020 at 03:09:48PM +0000, Marek Majkowski wrote:
> On Fri, Dec 6, 2019 at 2:17 AM Ivan Babrou <ivan@xxxxxxxxxxxxxx> wrote:
> >
> > I'm not very good at this, but the following works for me. If you this
> > is in general vicinity of what you expected, I can email patch
> > properly.
> >
>
> Thanks for the patch, I can confirm it works. I had this problem today
> when playing
> with gvisor. Gvisor is starting up in a fresh mount namespace and perf fails
> to read the symbols. Stracing perf shows:
>
> 11913 openat(AT_FDCWD, "/proc/9512/ns/mnt", O_RDONLY) = 197
> 11913 setns(197, CLONE_NEWNS) = 0
> 11913 stat("/home/marek/bin/runsc-debug", 0x7fffffff8480) = -1 ENOENT
> (No such file or directory)
> 11913 setns(196, CLONE_NEWNS) = 0
>
> Which of course makes no sense - the runsc-debug binary does not exist in the
> empty mount namespace of the restricted runsc process.

hi,
could you guys please share more details on what you run exactly,
and perhaps that change you mentioned?

thanks,
jirka