Re: perf not picking up symbols for namespaced processes

[Marek Majkowski]

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.

Marek