> Hi Miroslav, > > Maybe we should add a test to verify this new behavior? See sample > version below (lightly tested). We can add to this one, or patch > seperately if you prefer.
Thanks a lot, Joe. It looks nice. I'll include it in v3. One question below. > -->8-- -->8-- -->8-- -->8-- -->8-- -->8-- -->8-- -->8-- -->8-- -->8-- > > > >From c8c9f22e3816ca4c90ab7e7159d2ce536eaa5fad Mon Sep 17 00:00:00 2001 > From: Joe Lawrence <[email protected]> > Date: Mon, 14 Oct 2019 18:25:01 -0400 > Subject: [PATCH] selftests/livepatch: test interaction with ftrace_enabled > > Since livepatching depends upon ftrace handlers to implement "patched" > functionality, verify that the ftrace_enabled sysctl value interacts > with livepatch registration as expected. > > Signed-off-by: Joe Lawrence <[email protected]> > --- > tools/testing/selftests/livepatch/Makefile | 3 +- > .../testing/selftests/livepatch/functions.sh | 18 +++++ > .../selftests/livepatch/test-ftrace.sh | 65 +++++++++++++++++++ > 3 files changed, 85 insertions(+), 1 deletion(-) > create mode 100755 tools/testing/selftests/livepatch/test-ftrace.sh > > diff --git a/tools/testing/selftests/livepatch/Makefile > b/tools/testing/selftests/livepatch/Makefile > index fd405402c3ff..1886d9d94b88 100644 > --- a/tools/testing/selftests/livepatch/Makefile > +++ b/tools/testing/selftests/livepatch/Makefile > @@ -4,6 +4,7 @@ TEST_PROGS_EXTENDED := functions.sh > TEST_PROGS := \ > test-livepatch.sh \ > test-callbacks.sh \ > - test-shadow-vars.sh > + test-shadow-vars.sh \ > + test-ftrace.sh > > include ../lib.mk > diff --git a/tools/testing/selftests/livepatch/functions.sh > b/tools/testing/selftests/livepatch/functions.sh > index 79b0affd21fb..556252efece0 100644 > --- a/tools/testing/selftests/livepatch/functions.sh > +++ b/tools/testing/selftests/livepatch/functions.sh > @@ -52,6 +52,24 @@ function set_dynamic_debug() { > EOF > } > > +function push_ftrace_enabled() { > + FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) > +} Shouldn't we call push_ftrace_enabled() somewhere at the beginning of the test script? set_dynamic_debug() calls its push_dynamic_debug() directly, but set_ftrace_enabled() is different, because it is called more than once in the script. One could argue that ftrace_enabled has to be true at the beginning of testing anyway, but I think it would be cleaner. Btw, we should probably guarantee that ftrace_enabled is true when livepatch selftests are invoked. > +function pop_ftrace_enabled() { > + if [[ -n "$FTRACE_ENABLED" ]]; then > + sysctl kernel.ftrace_enabled="$FTRACE_ENABLED" > + fi > +} > +# set_ftrace_enabled() - save the current ftrace_enabled config and tweak > +# it for the self-tests. Set a script exit trap > +# that restores the original value. > +function set_ftrace_enabled() { > + local sysctl="$1" > + trap pop_ftrace_enabled EXIT INT TERM HUP > + result=$(sysctl kernel.ftrace_enabled="$1" 2>&1 | paste --serial > --delimiters=' ') > + echo "livepatch: $result" > /dev/kmsg > +} > + > # loop_until(cmd) - loop a command until it is successful or $MAX_RETRIES, > # sleep $RETRY_INTERVAL between attempts > # cmd - command and its arguments to run Miroslav
