Messages in this thread | | | Date | Sun, 27 Apr 2014 18:16:32 +0200 | From | Jiri Olsa <> | Subject | Re: [PATCH] perf x86: Fix perf to use non-executable stack, again |
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On Sun, Apr 27, 2014 at 06:07:30PM +0200, Mathias Krause wrote: > On 27 April 2014 12:39, Jiri Olsa <jolsa@redhat.com> wrote: > > On Sun, Apr 27, 2014 at 12:03:50PM +0200, Mathias Krause wrote: > > [...] > >> 2/ What if somebody tries to add/link code to perf that makes use of > >> nested functions? That'll make perf fail as the trampoline code > >> generated by gcc won't be executable due to the enforced > >> non-executable stack by -Wl,-z,noexecstack. > > > > I guess in that case he would change the Makefile as well? > > Not necessarily. What if a later version of a library already used by > perf needs an executable stack because it now makes use of nested > functions? Unlikely, though in that case no change to perf would be > made, but perf would then require an executable stack, too.
I tried you can run binary with noexecstack having dynamic library dependency wit execstack
> > Anyway, as Ingo votes for the global linker option as well, I'll send > a v2 of the patch containing your suggested linker flag.
cool
> > > anyway I have no objection for leaving that code in assembly > > objects, but I suggest we use the global option as well to > > prevent any future surprise.. > > Okay. > > > or insert test case for perf's executable stack to 'perf test' > > That won't work for systems preventing processes getting an executable > stack in the first place. That was the reason I stumbled about the
could be disabled on such systems
jirka
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