[PATCH -next 5/5] mm/kmemleak-test: Add a test case for alloc_percpu

From: Chen Jun
Date: Sun Sep 20 2020 - 22:03:08 EST


After insmod kmemleak-test.ko, a leaking for alloc_percpu will be
reported as below:

kmemleak: alloc_percpu(sizeof(*elem)) = 00007dfdd26a2c40
:
:
unreferenced object 0x7dfdd26a2c40 (size 8):
comm "insmod", pid 183, jiffies 4294905864 (age 40.520s)
hex dump (first 8 bytes):
00 00 00 00 00 00 00 00 ........
backtrace:
[<(____ptrval____)>] pcpu_alloc+0x3ec/0x8c8
[<(____ptrval____)>] __alloc_percpu+0x18/0x28
[<(____ptrval____)>] 0xffff800008df525c
[<(____ptrval____)>] do_one_initcall+0x60/0x1d8
[<(____ptrval____)>] do_init_module+0x58/0x1d0
[<(____ptrval____)>] load_module+0x1d8c/0x23d0
[<(____ptrval____)>] __do_sys_finit_module+0xdc/0xf8
[<(____ptrval____)>] __arm64_sys_finit_module+0x20/0x30
[<(____ptrval____)>] el0_svc_common.constprop.3+0x68/0x170
[<(____ptrval____)>] do_el0_svc+0x24/0x90
[<(____ptrval____)>] el0_sync_handler+0x13c/0x1a8
[<(____ptrval____)>] el0_sync+0x158/0x180

Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx>
Signed-off-by: Chen Jun <chenjun102@xxxxxxxxxx>
---
mm/kmemleak-test.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/mm/kmemleak-test.c b/mm/kmemleak-test.c
index 75fe1b8c3226..8f3e4a60166b 100644
--- a/mm/kmemleak-test.c
+++ b/mm/kmemleak-test.c
@@ -79,6 +79,9 @@ static int __init kmemleak_test_init(void)
per_cpu(kmemleak_test_pointer, i));
}

+ pr_info("alloc_percpu(sizeof(*elem)) = %px\n",
+ alloc_percpu(sizeof(*elem)));
+
return 0;
}
module_init(kmemleak_test_init);
--
2.25.0