From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 776F0C46CA1 for ; Mon, 18 Sep 2023 11:00:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234280AbjIRLA3 (ORCPT ); Mon, 18 Sep 2023 07:00:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237673AbjIRLAS (ORCPT ); Mon, 18 Sep 2023 07:00:18 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17A518F; Mon, 18 Sep 2023 04:00:12 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E5A57C433C7; Mon, 18 Sep 2023 11:00:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695034811; bh=mUP6+EOkqcXwwHbp/HXe6HO9SgJ+ru7fakc6rUq1+Cc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JRcMHnFI1H4CVwaI8yhCmtOPdp+FzuUGK1NYH1ESGOZO88hXQArQ9JBPK0zrjBcM/ SVKzKoQsepWlY0yExn8n7Ktxh8iH6SMKq8HwLfEgZKThDRR58TZfmcmJBX3wCz+QRI 1yTCoU05IGB50cuGOB3BbwoozrxtM6BByqKgN9V9ibyaLCTvwOf8e7SMuHj1toAI2Z F80Ak+P2/ZW89YQkuFbzt2KiHl5+SIf6CFdZcBUJdxdFRESd4C2pevyskRCW8nXDSq 97X1VirI6/6iAIoTX7GTjXfu0vGeDgvaiXdpfrgzk007VZTiIpwgcST8HgVxgjQAa7 PHdi2af/UUV+g== From: SeongJae Park To: Jinjie Ruan Cc: sj@kernel.org, akpm@linux-foundation.org, brendan.higgins@linux.dev, feng.tang@intel.com, damon@lists.linux.dev, linux-mm@kvack.org, kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/2] mm/damon/core-test: Fix memory leak in damon_new_region() Date: Mon, 18 Sep 2023 11:00:09 +0000 Message-Id: <20230918110009.78365-1-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230918074759.3895339-2-ruanjinjie@huawei.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jinjie, On Mon, 18 Sep 2023 15:47:58 +0800 Jinjie Ruan 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 Other than the above trivial nit, Reviewed-by: SeongJae Park > --- > 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 > >