[for-linus][PATCH 5/7] tracing: define needed config DYNAMIC_FTRACE_WITH_ARGS

From: Steven Rostedt
Date: Wed Aug 11 2021 - 21:14:14 EST


From: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx>

Commit 2860cd8a2353 ("livepatch: Use the default ftrace_ops instead of
REGS when ARGS is available") intends to enable config LIVEPATCH when
ftrace with ARGS is available. However, the chain of configs to enable
LIVEPATCH is incomplete, as HAVE_DYNAMIC_FTRACE_WITH_ARGS is available,
but the definition of DYNAMIC_FTRACE_WITH_ARGS, combining DYNAMIC_FTRACE
and HAVE_DYNAMIC_FTRACE_WITH_ARGS, needed to enable LIVEPATCH, is missing
in the commit.

Fortunately, ./scripts/checkkconfigsymbols.py detects this and warns:

DYNAMIC_FTRACE_WITH_ARGS
Referencing files: kernel/livepatch/Kconfig

So, define the config DYNAMIC_FTRACE_WITH_ARGS analogously to the already
existing similar configs, DYNAMIC_FTRACE_WITH_REGS and
DYNAMIC_FTRACE_WITH_DIRECT_CALLS, in ./kernel/trace/Kconfig to connect the
chain of configs.

Link: https://lore.kernel.org/kernel-janitors/CAKXUXMwT2zS9fgyQHKUUiqo8ynZBdx2UEUu1WnV_q0OCmknqhw@xxxxxxxxxxxxxx/
Link: https://lkml.kernel.org/r/20210806195027.16808-1-lukas.bulwahn@xxxxxxxxx

Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Jiri Kosina <jikos@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Miroslav Benes <mbenes@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 2860cd8a2353 ("livepatch: Use the default ftrace_ops instead of REGS when ARGS is available")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/Kconfig | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index d567b1717c4c..3ee23f4d437f 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -219,6 +219,11 @@ config DYNAMIC_FTRACE_WITH_DIRECT_CALLS
depends on DYNAMIC_FTRACE_WITH_REGS
depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS

+config DYNAMIC_FTRACE_WITH_ARGS
+ def_bool y
+ depends on DYNAMIC_FTRACE
+ depends on HAVE_DYNAMIC_FTRACE_WITH_ARGS
+
config FUNCTION_PROFILER
bool "Kernel function profiler"
depends on FUNCTION_TRACER
--
2.30.2