linux - tools/objtool/tests/generic/test-function-removal.sh

34 lines · 1.2 KiB

1	#!/bin/bash
2	# SPDX-License-Identifier: GPL-2.0
3	#
4	# A patch which deletes a function leaves a symbol in the original with no
5	# counterpart in the patched object. klp diff cannot correlate it, and must
6	# say so and carry on: livepatching cannot remove code from a running kernel,
7	# so what matters is that the surviving caller is patched and the deleted
8	# function is not dragged into the patch module.
9	#
10	# Cloning it would be worse than useless -- dead code in the patch, plus
11	# whatever it references, resolved against a kernel where it may not exist.
12
13	. "$(dirname "$0")/../lib.sh"
14
15	setup
16	build_pair function_removal.c
17
18	# One-sided by construction: present in the original, gone from the patched.
19	has_input_symbol orig.o going_away \|\|
20	fail "fixture has no going_away in the original"
21	has_input_symbol patched.o going_away &&
22	fail "fixture still has going_away in the patched object"
23
24	run_diff
25
26	assert_diff_log 'no correlation: going_away'
27
28	# The caller changed, so it is patched ...
29	assert_patched caller
30	# ... and the deleted function comes along in no form at all.
31	assert_not_patched going_away
32	assert_no_symbol going_away
33
34	pass "deleted function reported as uncorrelated and left out of the patch"