From patchwork Mon Oct 23 03:28:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xu Yilun X-Patchwork-Id: 13432310 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 7FC6DCDB474 for ; Mon, 23 Oct 2023 03:30:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233290AbjJWDax (ORCPT ); Sun, 22 Oct 2023 23:30:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44522 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233353AbjJWDaY (ORCPT ); Sun, 22 Oct 2023 23:30:24 -0400 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A517C10D3; Sun, 22 Oct 2023 20:30:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698031815; x=1729567815; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=KyMoHWShCcyV3MRbZKpVC/E1DYBRT6LqwzkBXptqrAo=; b=MVYBsTvjipWSPUfEAWKwEazuwuFGsD9t8K10AxLyA567jfWDB0D2+rnb 4qndguMndfcI8U+nOsc700nL0kRL+3tn4EUVpfYflNSMKzQVXij6Fhn0M cSjQbYCQCrRaovgoZi9bnOoKV+ZKjEyiFCL9xlRl9k9LU+kwl742LIjVe UVAK/oxeax8xlOdQ0FZ48jzOm/SJOERgHgIWpDqnF5TKGRUjz1YUIklJo n3hQxii/pOxwVbwpuOqBvZCPido/E1OgiFDropS5OIkdyVgA4YBLaZx8t xA7Bjsn+4vEmq3jSq+TXyzZgo8HqJ5eQRxMfuqJcYDm11g8zlm0v1WDcp A==; X-IronPort-AV: E=McAfee;i="6600,9927,10871"; a="5380110" X-IronPort-AV: E=Sophos;i="6.03,244,1694761200"; d="scan'208";a="5380110" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Oct 2023 20:30:15 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10871"; a="881617680" X-IronPort-AV: E=Sophos;i="6.03,244,1694761200"; d="scan'208";a="881617680" Received: from yilunxu-optiplex-7050.sh.intel.com ([10.239.159.165]) by orsmga004.jf.intel.com with ESMTP; 22 Oct 2023 20:30:13 -0700 From: Xu Yilun To: gregkh@linuxfoundation.org Cc: hao.wu@intel.com, mdf@kernel.org, linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org, yilun.xu@intel.com Subject: [RESEND PATCH 2/2] fpga: Fix memory leak for fpga_region_test_class_find() Date: Mon, 23 Oct 2023 11:28:57 +0800 Message-Id: <20231023032857.902699-3-yilun.xu@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231023032857.902699-1-yilun.xu@linux.intel.com> References: <20231023032857.902699-1-yilun.xu@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org From: Jinjie Ruan fpga_region_class_find() in fpga_region_test_class_find() will call get_device() if the data is matched, which will increment refcount for dev->kobj, so it should call put_device() to decrement refcount for dev->kobj to free the region, because fpga_region_unregister() will call fpga_region_dev_release() only when the refcount for dev->kobj is zero but fpga_region_test_init() call device_register() in fpga_region_register_full(), which also increment refcount. So call put_device() after calling fpga_region_class_find() in fpga_region_test_class_find(). After applying this patch, the following memory leak is never detected. unreferenced object 0xffff88810c8ef000 (size 1024): comm "kunit_try_catch", pid 1875, jiffies 4294715298 (age 836.836s) hex dump (first 32 bytes): b8 d1 fb 05 81 88 ff ff 08 f0 8e 0c 81 88 ff ff ................ 08 f0 8e 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [] kmalloc_trace+0x27/0xa0 [] fpga_region_register_full+0x51/0x430 [fpga_region] [] 0xffffffffa0228e47 [] kunit_try_run_case+0xdd/0x250 [] kunit_generic_run_threadfn_adapter+0x4a/0x90 [] kthread+0x2b5/0x380 [] ret_from_fork+0x2d/0x70 [] ret_from_fork_asm+0x11/0x20 unreferenced object 0xffff888105fbd1b8 (size 8): comm "kunit_try_catch", pid 1875, jiffies 4294715298 (age 836.836s) hex dump (first 8 bytes): 72 65 67 69 6f 6e 30 00 region0. backtrace: [] __kmalloc_node_track_caller+0x53/0x150 [] kvasprintf+0xb0/0x130 [] kobject_set_name_vargs+0x41/0x110 [] dev_set_name+0xab/0xe0 [] fpga_region_register_full+0x312/0x430 [fpga_region] [] 0xffffffffa0228e47 [] kunit_try_run_case+0xdd/0x250 [] kunit_generic_run_threadfn_adapter+0x4a/0x90 [] kthread+0x2b5/0x380 [] ret_from_fork+0x2d/0x70 [] ret_from_fork_asm+0x11/0x20 unreferenced object 0xffff88810b3b8a00 (size 256): comm "kunit_try_catch", pid 1875, jiffies 4294715298 (age 836.836s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 08 8a 3b 0b 81 88 ff ff ..........;..... 08 8a 3b 0b 81 88 ff ff e0 ac 04 83 ff ff ff ff ..;............. backtrace: [] kmalloc_trace+0x27/0xa0 [] device_add+0xa2a/0x15e0 [] fpga_region_register_full+0x321/0x430 [fpga_region] [] 0xffffffffa0228e47 [] kunit_try_run_case+0xdd/0x250 [] kunit_generic_run_threadfn_adapter+0x4a/0x90 [] kthread+0x2b5/0x380 [] ret_from_fork+0x2d/0x70 [] ret_from_fork_asm+0x11/0x20 Fixes: 64a5f972c93d ("fpga: add an initial KUnit suite for the FPGA Region") Signed-off-by: Jinjie Ruan Reviewed-by: Marco Pagani Acked-by: Xu Yilun Link: https://lore.kernel.org/r/20231007094321.3447084-1-ruanjinjie@huawei.com [yilun.xu@intel.com: slightly changes the commit message] Signed-off-by: Xu Yilun --- drivers/fpga/tests/fpga-region-test.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/fpga/tests/fpga-region-test.c b/drivers/fpga/tests/fpga-region-test.c index 9f9d50ee7871..baab07e3fc59 100644 --- a/drivers/fpga/tests/fpga-region-test.c +++ b/drivers/fpga/tests/fpga-region-test.c @@ -93,6 +93,8 @@ static void fpga_region_test_class_find(struct kunit *test) region = fpga_region_class_find(NULL, &ctx->region_pdev->dev, fake_region_match); KUNIT_EXPECT_PTR_EQ(test, region, ctx->region); + + put_device(®ion->dev); } /*