diff options
| author | Puranjay Mohan <puranjay@kernel.org> | 2026-09-16 11:43:08 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2026-09-21 11:02:47 +0200 |
| commit | fbb79ff9a6638aeb5b7a5f7db25afd033e6edd96 (patch) | |
| tree | 5f3b46c551187a6f6f1f41ffb4d1cf45507414ea /tools/objtool | |
| parent | 960c3e352bac749c35041d683f32bdde467a2960 (diff) | |
objtool/klp: Add test for static local correlation
A static local must be correlated with its original rather than duplicated.
The replacement has to reach the existing variable through a klp
relocation; a fresh definition would discard whatever state the running
kernel accumulated.
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Assisted-by: Claude:claude-opus-5
Link: https://patch.msgid.link/20260916184351.2720310-16-song@kernel.org
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/tests/generic/fixtures/static_local.c | 17 | ||||
| -rwxr-xr-x | tools/objtool/tests/generic/test-static-local.sh | 24 |
2 files changed, 41 insertions, 0 deletions
diff --git a/tools/objtool/tests/generic/fixtures/static_local.c b/tools/objtool/tests/generic/fixtures/static_local.c new file mode 100644 index 000000000000..f2f025d00a39 --- /dev/null +++ b/tools/objtool/tests/generic/fixtures/static_local.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Static local in a patched function. */ + +static const char __modinfo[] + __attribute__((section(".modinfo"), used, aligned(1))) = "\0name=vmlinux"; + +int target(int x) +{ + static int counter; + + counter += 1; +#ifdef PATCHED + return x + counter + 1; +#else + return x + counter; +#endif +} diff --git a/tools/objtool/tests/generic/test-static-local.sh b/tools/objtool/tests/generic/test-static-local.sh new file mode 100755 index 000000000000..d57efa64dfd9 --- /dev/null +++ b/tools/objtool/tests/generic/test-static-local.sh @@ -0,0 +1,24 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# A static local must be correlated with the original, not duplicated: a second +# copy would discard the state the running kernel accumulated. + +. "$(dirname "$0")/../lib.sh" + +setup +build_pair static_local.c + +in_symbols orig.o | grep -q 'counter' || + probe_skip "compiler emitted no distinct static local symbol" + +run_diff +assert_patched target + +out_symbols | grep -q '\.klp\.sym\..*\.counter' || + fail "static local not referenced through a klp relocation" + +out_symbols | grep 'counter' | grep -qvE 'UND|\.klp\.(sym|tombstone)' && + fail "static local was given a fresh definition" + +pass "static local correlated rather than duplicated" |