Re: [PATCH 2/2] selftests: livepatch: functions.sh: Workaround heredoc on older bash

[Marcos Paulo de Souza]

On Mon, 2026-02-23 at 10:42 -0500, Joe Lawrence wrote:
> On Fri, Feb 20, 2026 at 11:12:34AM -0300, Marcos Paulo de Souza
> wrote:
> > When running current selftests on older distributions like SLE12-
> > SP5 that
> > contains an older bash trips over heredoc. Convert it to plain echo
> > calls, which ends up with the same result.
> > 
> 
> Acked-by: Joe Lawrence <joe.lawrence@xxxxxxxxxx>

Thanks for the review Joe!

> 
> Just curious, what's the bash/heredoc issue?  All I could find via
> google search was perhaps something to do with the temporary file
> implementation under the hood.

# ./test-ftrace.sh 
cat: -: No such file or directory
TEST: livepatch interaction with ftrace_enabled sysctl ... ^CQEMU:
Terminated

Somehow it doesn't understand the heredoc, but maybe I'm wrong...
either way, the change has the same outcome, so I believe that it
wasn't bad if we could change the cat for two echoes :)

Either way, if Petr or you think that this should be left as it is,
it's fine by me as well, I was just testing the change with an older
rootfs/kernels.

> 
> --
> Joe
> 
> > Signed-off-by: Marcos Paulo de Souza <mpdesouza@xxxxxxxx>
> > ---
> >  tools/testing/selftests/livepatch/functions.sh | 6 ++----
> >  1 file changed, 2 insertions(+), 4 deletions(-)
> > 
> > diff --git a/tools/testing/selftests/livepatch/functions.sh
> > b/tools/testing/selftests/livepatch/functions.sh
> > index 8ec0cb64ad94..45ed04c6296e 100644
> > --- a/tools/testing/selftests/livepatch/functions.sh
> > +++ b/tools/testing/selftests/livepatch/functions.sh
> > @@ -96,10 +96,8 @@ function pop_config() {
> >  }
> >  
> >  function set_dynamic_debug() {
> > -        cat <<-EOF > "$SYSFS_DEBUG_DIR/dynamic_debug/control"
> > -		file kernel/livepatch/* +p
> > -		func klp_try_switch_task -p
> > -		EOF
> > +	echo "file kernel/livepatch/* +p" >
> > "$SYSFS_DEBUG_DIR/dynamic_debug/control"
> > +	echo "func klp_try_switch_task -p" >
> > "$SYSFS_DEBUG_DIR/dynamic_debug/control"
> >  }
> >  
> >  function set_ftrace_enabled() {
> > 
> > -- 
> > 2.52.0
> >