From a0ce79253a96ee6bbcce90775ed342ef3153c68e Mon Sep 17 00:00:00 2001 From: Jinjie Ruan Date: Mon, 18 Sep 2023 20:09:51 +0800 Subject: [PATCH] mm/damon/core-test: fix memory leak in damon_new_ctx() When CONFIG_DAMON_KUNIT_TEST=y and making CONFIG_DEBUG_KMEMLEAK=y and CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN=y, the below memory leak is detected. The damon_ctx which is allocated by kzalloc() in damon_new_ctx() in damon_test_ops_registration() and damon_test_set_attrs() are not freed. So use damon_destroy_ctx() to free it. After applying this patch, the following memory leak is never detected unreferenced object 0xffff2b49c6968800 (size 512): comm "kunit_try_catch", pid 350, jiffies 4294895294 (age 557.028s) hex dump (first 32 bytes): 88 13 00 00 00 00 00 00 a0 86 01 00 00 00 00 00 ................ 00 87 93 03 00 00 00 00 0a 00 00 00 00 00 00 00 ................ backtrace: [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368 [<0000000073acab3b>] __kmem_cache_alloc_node+0x174/0x290 [<00000000b5f89cef>] kmalloc_trace+0x40/0x164 [<00000000eb19e83f>] damon_new_ctx+0x28/0xb4 [<00000000daf6227b>] damon_test_ops_registration+0x34/0x328 [<00000000559c4801>] kunit_try_run_case+0x50/0xac [<000000003932ed49>] kunit_generic_run_threadfn_adapter+0x20/0x2c [<000000003c3e9211>] kthread+0x124/0x130 [<0000000028f85bdd>] ret_from_fork+0x10/0x20 unreferenced object 0xffff2b49c1a9cc00 (size 512): comm "kunit_try_catch", pid 356, jiffies 4294895306 (age 557.000s) hex dump (first 32 bytes): 88 13 00 00 00 00 00 00 a0 86 01 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 0a 00 00 00 00 00 00 00 ................ backtrace: [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368 [<0000000073acab3b>] __kmem_cache_alloc_node+0x174/0x290 [<00000000b5f89cef>] kmalloc_trace+0x40/0x164 [<00000000eb19e83f>] damon_new_ctx+0x28/0xb4 [<00000000058495c4>] damon_test_set_attrs+0x30/0x1a8 [<00000000559c4801>] kunit_try_run_case+0x50/0xac [<000000003932ed49>] kunit_generic_run_threadfn_adapter+0x20/0x2c [<000000003c3e9211>] kthread+0x124/0x130 [<0000000028f85bdd>] ret_from_fork+0x10/0x20 Link: https://lkml.kernel.org/r/20230918120951.2230468-3-ruanjinjie@huawei.com Fixes: d1836a3b2a9a ("mm/damon/core-test: initialise context before test in damon_test_set_attrs()") Fixes: 4f540f5ab4f2 ("mm/damon/core-test: add a kunit test case for ops registration") Signed-off-by: Jinjie Ruan Reviewed-by: Feng Tang Reviewed-by: SeongJae Park Cc: Brendan Higgins Signed-off-by: Andrew Morton --- mm/damon/core-test.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h index 3959be35b901..649adf91ebc5 100644 --- a/mm/damon/core-test.h +++ b/mm/damon/core-test.h @@ -269,6 +269,8 @@ static void damon_test_ops_registration(struct kunit *test) /* Check double-registration failure again */ KUNIT_EXPECT_EQ(test, damon_register_ops(&ops), -EINVAL); + + damon_destroy_ctx(c); } static void damon_test_set_regions(struct kunit *test) @@ -346,6 +348,8 @@ static void damon_test_set_attrs(struct kunit *test) invalid_attrs = valid_attrs; invalid_attrs.aggr_interval = 4999; KUNIT_EXPECT_EQ(test, damon_set_attrs(c, &invalid_attrs), -EINVAL); + + damon_destroy_ctx(c); } static void damon_test_moving_sum(struct kunit *test)