From: Nathan Chancellor Date: Fri, 20 Mar 2026 21:29:33 +0000 (-0700) Subject: tracing: Adjust cmd_check_undefined to show unexpected undefined symbols X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=58b4bd18390ec3118d8577e19bdee0d01d40c31e;p=thirdparty%2Fkernel%2Fstable.git tracing: Adjust cmd_check_undefined to show unexpected undefined symbols When the check_undefined command in kernel/trace/Makefile fails, there is no output, making it hard to understand why the build failed. Capture the output of the $(NM) + grep command and print it when failing to make it clearer what the problem is. Fixes: a717943d8ecc ("tracing: Check for undefined symbols in simple_ring_buffer") Signed-off-by: Nathan Chancellor Reviewed-by: Vincent Donnefort Acked-by: Arnd Bergmann Link: https://patch.msgid.link/20260320-cmd_check_undefined-verbose-v1-1-54fc5b061f94@kernel.org Signed-off-by: Marc Zyngier --- diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index c5e14ffd36ee..d662c1a64cd5 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -174,7 +174,13 @@ UNDEFINED_ALLOWLIST = __asan __gcov __kasan __kcsan __hwasan __sancov __sanitize $(shell $(NM) -u $(obj)/undefsyms_base.o 2>/dev/null | awk '{print $$2}') quiet_cmd_check_undefined = NM $< - cmd_check_undefined = test -z "`$(NM) -u $< | grep -v $(addprefix -e , $(UNDEFINED_ALLOWLIST))`" + cmd_check_undefined = \ + undefsyms=$$($(NM) -u $< | grep -v $(addprefix -e , $(UNDEFINED_ALLOWLIST)) || true); \ + if [ -n "$$undefsyms" ]; then \ + echo "Unexpected symbols in $<:" >&2; \ + echo "$$undefsyms" >&2; \ + false; \ + fi $(obj)/%.o.checked: $(obj)/%.o $(obj)/undefsyms_base.o FORCE $(call if_changed,check_undefined)