[PATCH] kmemleak-test: drop __init to get better backtrace

From: Jim Cromie
Date: Thu May 25 2023 - 13:44:50 EST


Drop the __init on kmemleak_test_init(). With it, the storage is
reclaimed, but then the symbol isn't available for "%pS" rendering,
and the backtrace gets a bare pointer where the actual leak happened.

unreferenced object 0xffff88800a2b0800 (size 1024):
comm "modprobe", pid 413, jiffies 4294953430
hex dump (first 32 bytes):
73 02 00 00 75 01 00 68 02 00 00 01 00 00 00 04 s...u..h........
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000fabad728>] kmalloc_trace+0x26/0x90
[<00000000ef738764>] 0xffffffffc02350a2
[<00000000004e5795>] do_one_initcall+0x43/0x210
[<00000000d768905e>] do_init_module+0x4a/0x210
[<0000000087135ab5>] __do_sys_finit_module+0x93/0xf0
[<000000004fcb1fa2>] do_syscall_64+0x34/0x80
[<00000000c73c8d9d>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

with __init gone, that trace entry renders like:

[<00000000ef738764>] kmemleak_test_init+<offset>/<size>

Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
---
samples/kmemleak/kmemleak-test.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/samples/kmemleak/kmemleak-test.c b/samples/kmemleak/kmemleak-test.c
index 7b476eb8285f..6ced5ddd99d4 100644
--- a/samples/kmemleak/kmemleak-test.c
+++ b/samples/kmemleak/kmemleak-test.c
@@ -32,7 +32,7 @@ static DEFINE_PER_CPU(void *, kmemleak_test_pointer);
* Some very simple testing. This function needs to be extended for
* proper testing.
*/
-static int __init kmemleak_test_init(void)
+static int kmemleak_test_init(void)
{
struct test_node *elem;
int i;
--
2.40.1