Re: [PATCH v2] selftests/ftrace: adjust offset for kprobe syntax error test

[Shuah Khan]

On 12/3/24 18:20, Steven Rostedt wrote:
> On Tue, 3 Dec 2024 18:01:06 -0700
> Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> wrote:
>
> > On 12/2/24 12:41, Steven Rostedt wrote:
> > > On Sat, 30 Nov 2024 01:56:21 +0530
> > > Hari Bathini <hbathini@xxxxxxxxxxxxx> wrote:
> > >    
> > > > In 'NOFENTRY_ARGS' test case for syntax check, any offset X of
> > > > `vfs_read+X` except function entry offset (0) fits the criterion,
> > > > even if that offset is not at instruction boundary, as the parser
> > > > comes before probing. But with "ENDBR64" instruction on x86, offset
> > > > 4 is treated as function entry. So, X can't be 4 as well. Thus, 8
> > > > was used as offset for the test case. On 64-bit powerpc though, any
> > > > offset <= 16 can be considered function entry depending on build
> > > > configuration (see arch_kprobe_on_func_entry() for implementation
> > > > details). So, use `vfs_read+20` to accommodate that scenario too.
> > > >
> > > > Suggested-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > > > Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxx>
> > >
> > > Acked-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
> > >
> > > Shuah,
> > >
> > > Can you take this through your tree?
> >
> > Yes I can take it. I do have question about whether this is
> > a fix - sounds like it is from the change log.
> >
> > Clearly stating that it is a fix will help so it can be picked
> > up for stables.
>
> I would say it's a fix, as the test currently fails in certain scenarios
> for powerpc.
>
> You can add:
>
> Fixes: 4231f30fcc34a ("selftests/ftrace: Add BTF arguments test cases")

I applied this to linux-kselftest fixes - will send it up for rc2 or rc3

thanks,
-- Shuah