[PATCH v2 0/2] mm/damon/core-test: Fix memory leaks in core-test

[PATCH v2 0/2] mm/damon/core-test: Fix memory leaks in core-test

[Jinjie Ruan]

There are a few memory leak in core-test which is detected by kmemleak,
the patch set fix the above issue.

Changes in v2:
- Add Reviewed-by.
- Rebased on mm-unstable.
- Replace the damon_del_region() with damon_destroy_region() rather than
  calling damon_free_region().
- Update the commit message.

Jinjie Ruan (2):
  mm/damon/core-test: Fix memory leak in damon_new_region()
  mm/damon/core-test: Fix memory leak in damon_new_ctx()

 mm/damon/core-test.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

-- 
2.34.1

[PATCH v2 1/2] mm/damon/core-test: Fix memory leak in damon_new_region()

[Jinjie Ruan]

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_region which is allocated by kmem_cache_alloc() in
damon_new_region() in damon_test_regions() and
damon_test_update_monitoring_result() are not freed. So use
damon_free_region() to free it. After applying this patch, the following
memory leak is never detected.

    unreferenced object 0xffff2b49c3edc000 (size 56):
      comm "kunit_try_catch", pid 338, jiffies 4294895280 (age 557.084s)
      hex dump (first 32 bytes):
        01 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00  ................
        00 00 00 00 00 00 00 00 00 00 00 00 49 2b ff ff  ............I+..
      backtrace:
        [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368
        [<00000000b528f67c>] kmem_cache_alloc+0x168/0x284
        [<000000008603f022>] damon_new_region+0x28/0x54
        [<00000000a3b8c64e>] damon_test_regions+0x38/0x270
        [<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 0xffff2b49c5b20000 (size 56):
      comm "kunit_try_catch", pid 354, jiffies 4294895304 (age 556.988s)
      hex dump (first 32 bytes):
        03 00 00 00 00 00 00 00 07 00 00 00 00 00 00 00  ................
        00 00 00 00 00 00 00 00 96 00 00 00 49 2b ff ff  ............I+..
      backtrace:
        [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368
        [<00000000b528f67c>] kmem_cache_alloc+0x168/0x284
        [<000000008603f022>] damon_new_region+0x28/0x54
        [<00000000ca019f80>] damon_test_update_monitoring_result+0x18/0x34
        [<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

Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Fixes: f4c978b6594b ("mm/damon/core-test: add a test for damon_update_monitoring_results()")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
---
v2:
- Replace the damon_del_region() with damon_destroy_region() rather than
  calling damon_free_region().
- Update the commit message.
---
 mm/damon/core-test.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
index 79f1f12e0dd5..3959be35b901 100644
--- a/mm/damon/core-test.h
+++ b/mm/damon/core-test.h
@@ -30,7 +30,7 @@ static void damon_test_regions(struct kunit *test)
 	damon_add_region(r, t);
 	KUNIT_EXPECT_EQ(test, 1u, damon_nr_regions(t));
 
-	damon_del_region(r, t);
+	damon_destroy_region(r, t);
 	KUNIT_EXPECT_EQ(test, 0u, damon_nr_regions(t));
 
 	damon_free_target(t);
@@ -321,6 +321,8 @@ static void damon_test_update_monitoring_result(struct kunit *test)
 	damon_update_monitoring_result(r, &old_attrs, &new_attrs);
 	KUNIT_EXPECT_EQ(test, r->nr_accesses, 150);
 	KUNIT_EXPECT_EQ(test, r->age, 20);
+
+	damon_free_region(r);
 }
 
 static void damon_test_set_attrs(struct kunit *test)
-- 
2.34.1

[PATCH v2 2/2] mm/damon/core-test: Fix memory leak in damon_new_ctx()

[Jinjie Ruan]

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

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 <ruanjinjie@huawei.com>
Reviewed-by: Feng Tang <feng.tang@intel.com>
---
v2:
- Add Reviewed-by.
- Rebased on mm-unstable.
- Update the commit message.
---
 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)
-- 
2.34.1

Re: [PATCH v2 1/2] mm/damon/core-test: Fix memory leak in damon_new_region()

[SeongJae Park]

Hi Jinjie,

On Mon, 18 Sep 2023 15:47:58 +0800 Jinjie Ruan <ruanjinjie@huawei.com> wrote:

> 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_region which is allocated by kmem_cache_alloc() in
> damon_new_region() in damon_test_regions() and
> damon_test_update_monitoring_result() are not freed. So use
> damon_free_region() to free it.

Nit.  This patch is not directly adding use of damon_free_region() but replaces
damon_del_region() call with damon_destroy_region(), so that it calls both
damon_del_region() and damon_free_region().

I think this part might better to be re-written?

> After applying this patch, the following
> memory leak is never detected.
> 
>     unreferenced object 0xffff2b49c3edc000 (size 56):
>       comm "kunit_try_catch", pid 338, jiffies 4294895280 (age 557.084s)
>       hex dump (first 32 bytes):
>         01 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00  ................
>         00 00 00 00 00 00 00 00 00 00 00 00 49 2b ff ff  ............I+..
>       backtrace:
>         [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368
>         [<00000000b528f67c>] kmem_cache_alloc+0x168/0x284
>         [<000000008603f022>] damon_new_region+0x28/0x54
>         [<00000000a3b8c64e>] damon_test_regions+0x38/0x270
>         [<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 0xffff2b49c5b20000 (size 56):
>       comm "kunit_try_catch", pid 354, jiffies 4294895304 (age 556.988s)
>       hex dump (first 32 bytes):
>         03 00 00 00 00 00 00 00 07 00 00 00 00 00 00 00  ................
>         00 00 00 00 00 00 00 00 96 00 00 00 49 2b ff ff  ............I+..
>       backtrace:
>         [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368
>         [<00000000b528f67c>] kmem_cache_alloc+0x168/0x284
>         [<000000008603f022>] damon_new_region+0x28/0x54
>         [<00000000ca019f80>] damon_test_update_monitoring_result+0x18/0x34
>         [<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
> 
> Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
> Fixes: f4c978b6594b ("mm/damon/core-test: add a test for damon_update_monitoring_results()")
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>

Other than the above trivial nit,

Reviewed-by: SeongJae Park <sj@kernel.org>

> ---
> v2:
> - Replace the damon_del_region() with damon_destroy_region() rather than
>   calling damon_free_region().
> - Update the commit message.

And thank you for making the changes.


Thanks,
SJ

> ---
>  mm/damon/core-test.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
> index 79f1f12e0dd5..3959be35b901 100644
> --- a/mm/damon/core-test.h
> +++ b/mm/damon/core-test.h
> @@ -30,7 +30,7 @@ static void damon_test_regions(struct kunit *test)
>  	damon_add_region(r, t);
>  	KUNIT_EXPECT_EQ(test, 1u, damon_nr_regions(t));
>  
> -	damon_del_region(r, t);
> +	damon_destroy_region(r, t);
>  	KUNIT_EXPECT_EQ(test, 0u, damon_nr_regions(t));
>  
>  	damon_free_target(t);
> @@ -321,6 +321,8 @@ static void damon_test_update_monitoring_result(struct kunit *test)
>  	damon_update_monitoring_result(r, &old_attrs, &new_attrs);
>  	KUNIT_EXPECT_EQ(test, r->nr_accesses, 150);
>  	KUNIT_EXPECT_EQ(test, r->age, 20);
> +
> +	damon_free_region(r);
>  }
>  
>  static void damon_test_set_attrs(struct kunit *test)
> -- 
> 2.34.1
> 
> 

Re: [PATCH v2 2/2] mm/damon/core-test: Fix memory leak in damon_new_ctx()

[SeongJae Park]

Hi Jinjie,

On Mon, 18 Sep 2023 15:47:59 +0800 Jinjie Ruan <ruanjinjie@huawei.com> wrote:

> 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
> 
> 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 <ruanjinjie@huawei.com>
> Reviewed-by: Feng Tang <feng.tang@intel.com>

Reviewed-by: SeongJae Park <sj@kernel.org>


Thanks,
SJ

> ---
> v2:
> - Add Reviewed-by.
> - Rebased on mm-unstable.
> - Update the commit message.
> ---
>  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)
> -- 
> 2.34.1
> 
> 

Re: [PATCH v2 1/2] mm/damon/core-test: Fix memory leak in damon_new_region()

[Ruan Jinjie]

On 2023/9/18 19:00, SeongJae Park wrote:
> Hi Jinjie,
> 
> On Mon, 18 Sep 2023 15:47:58 +0800 Jinjie Ruan <ruanjinjie@huawei.com> wrote:
> 
>> 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_region which is allocated by kmem_cache_alloc() in
>> damon_new_region() in damon_test_regions() and
>> damon_test_update_monitoring_result() are not freed. So use
>> damon_free_region() to free it.
> 
> Nit.  This patch is not directly adding use of damon_free_region() but replaces
> damon_del_region() call with damon_destroy_region(), so that it calls both
> damon_del_region() and damon_free_region().
> 
> I think this part might better to be re-written?

OK. Thank you!

> 
>> After applying this patch, the following
>> memory leak is never detected.
>>
>>     unreferenced object 0xffff2b49c3edc000 (size 56):
>>       comm "kunit_try_catch", pid 338, jiffies 4294895280 (age 557.084s)
>>       hex dump (first 32 bytes):
>>         01 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00  ................
>>         00 00 00 00 00 00 00 00 00 00 00 00 49 2b ff ff  ............I+..
>>       backtrace:
>>         [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368
>>         [<00000000b528f67c>] kmem_cache_alloc+0x168/0x284
>>         [<000000008603f022>] damon_new_region+0x28/0x54
>>         [<00000000a3b8c64e>] damon_test_regions+0x38/0x270
>>         [<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 0xffff2b49c5b20000 (size 56):
>>       comm "kunit_try_catch", pid 354, jiffies 4294895304 (age 556.988s)
>>       hex dump (first 32 bytes):
>>         03 00 00 00 00 00 00 00 07 00 00 00 00 00 00 00  ................
>>         00 00 00 00 00 00 00 00 96 00 00 00 49 2b ff ff  ............I+..
>>       backtrace:
>>         [<0000000088e71769>] slab_post_alloc_hook+0xb8/0x368
>>         [<00000000b528f67c>] kmem_cache_alloc+0x168/0x284
>>         [<000000008603f022>] damon_new_region+0x28/0x54
>>         [<00000000ca019f80>] damon_test_update_monitoring_result+0x18/0x34
>>         [<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
>>
>> Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
>> Fixes: f4c978b6594b ("mm/damon/core-test: add a test for damon_update_monitoring_results()")
>> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> 
> Other than the above trivial nit,
> 
> Reviewed-by: SeongJae Park <sj@kernel.org>
> 
>> ---
>> v2:
>> - Replace the damon_del_region() with damon_destroy_region() rather than
>>   calling damon_free_region().
>> - Update the commit message.
> 
> And thank you for making the changes.
> 
> 
> Thanks,
> SJ
> 
>> ---
>>  mm/damon/core-test.h | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
>> index 79f1f12e0dd5..3959be35b901 100644
>> --- a/mm/damon/core-test.h
>> +++ b/mm/damon/core-test.h
>> @@ -30,7 +30,7 @@ static void damon_test_regions(struct kunit *test)
>>  	damon_add_region(r, t);
>>  	KUNIT_EXPECT_EQ(test, 1u, damon_nr_regions(t));
>>  
>> -	damon_del_region(r, t);
>> +	damon_destroy_region(r, t);
>>  	KUNIT_EXPECT_EQ(test, 0u, damon_nr_regions(t));
>>  
>>  	damon_free_target(t);
>> @@ -321,6 +321,8 @@ static void damon_test_update_monitoring_result(struct kunit *test)
>>  	damon_update_monitoring_result(r, &old_attrs, &new_attrs);
>>  	KUNIT_EXPECT_EQ(test, r->nr_accesses, 150);
>>  	KUNIT_EXPECT_EQ(test, r->age, 20);
>> +
>> +	damon_free_region(r);
>>  }
>>  
>>  static void damon_test_set_attrs(struct kunit *test)
>> -- 
>> 2.34.1
>>
>>