From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outbound.pv.icloud.com (p-west1-cluster3-host1-snip4-10.eps.apple.com [57.103.66.123]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 73674251799 for ; Thu, 10 Jul 2025 11:57:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=57.103.66.123 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752148650; cv=none; b=HB0HoA+c0vW8dbOW0OyVIBAkh7C0zjUAzgU+AusCIHa95Cb0UoAQDVHbBjyy1FqHaFCnWW++ALZGT4wdizbSwfom6gzVLkc1cfZxoADmlSBvObCB5x+3FjcHoPB57dL8bosOC4c4/lPR4L253EVNd3O+NCC3ciOeGtdfZrzFYIM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752148650; c=relaxed/simple; bh=wKm5Ok1D3zI9n6oV/H9sgCnwtCpc6AvdeR7Tt6S9+jU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=kDrQRLSFyIqbOMYJgPEynMGnKNeU2YHX3+HHgBI1MjfQJ3Cn8SzL2cyWhqAxybidEYaBjYZvjpduXiZNp8fRaBtd2Yug8rhuFXhPUJ5fKBhrkpu1tMGQfYOOdxphRRQoKoOgYNBkJtF1/frL573upB8WMGgKcmO+NDgriswuyHU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=icloud.com; spf=pass smtp.mailfrom=icloud.com; dkim=pass (2048-bit key) header.d=icloud.com header.i=@icloud.com header.b=B+SuO5bh; arc=none smtp.client-ip=57.103.66.123 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=icloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=icloud.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=icloud.com header.i=@icloud.com header.b="B+SuO5bh" Received: from outbound.pv.icloud.com (unknown [127.0.0.2]) by outbound.pv.icloud.com (Postfix) with ESMTPS id EA7D31800199; Thu, 10 Jul 2025 11:57:25 +0000 (UTC) Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=icloud.com; s=1a1hai; bh=J5y+0r7klm10pX3hlor2G5tej0Jv9rOx8255KUf0j6Y=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:x-icloud-hme; b=B+SuO5bheY405MnVzSaQPNBye54Z8YLjomj7mWIW7GS9LTksoq7orq2bdEOsqw27smZ5NsfNDVaZdvxPAuyfPUUVE97tIEADQiQznsFzBT/SUfXFG/7gLvbYqgaRhdvjXVdYg9/DjdcCxlUbdW6GTIW0QBv1y6aLW+Frh5Pxbpj9mNnxMxc++H1PD54RmiMzUJHyv7JWj9J9LJumdk0/AYtGAzMJrPSr4CHm4YNCe4pP9vDhqSJdv+8kXgT14a8XWnirLN6+XeEvaLHZmyr7/GtOpge8YfKpdXZn3srsJbVNzfzTDty6eMQWtqy7zUVcXd2212u4xHUsgSYnrqvRdA== Received: from [192.168.1.26] (pv-asmtp-me-k8s.p00.prod.me.com [17.56.9.36]) by outbound.pv.icloud.com (Postfix) with ESMTPSA id 3CA1118000B8; Thu, 10 Jul 2025 11:57:22 +0000 (UTC) From: Zijun Hu Date: Thu, 10 Jul 2025 19:56:47 +0800 Subject: [PATCH v5 4/8] char: misc: Add a case to test registering miscdevice again without reinitialization Precedence: bulk X-Mailing-List: linux-parisc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250710-rfc_miscdev-v5-4-b3940297db16@oss.qualcomm.com> References: <20250710-rfc_miscdev-v5-0-b3940297db16@oss.qualcomm.com> In-Reply-To: <20250710-rfc_miscdev-v5-0-b3940297db16@oss.qualcomm.com> To: Arnd Bergmann , Greg Kroah-Hartman , "James E.J. Bottomley" , Helge Deller , "David S. Miller" , Andreas Larsson Cc: Thadeu Lima de Souza Cascardo , Zijun Hu , linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org, Zijun Hu X-Mailer: b4 0.14.2 X-Proofpoint-GUID: Rv-wiHaEWA-6rhr_aT8ESYmcOD0-UsqM X-Proofpoint-ORIG-GUID: Rv-wiHaEWA-6rhr_aT8ESYmcOD0-UsqM X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzEwMDEwMiBTYWx0ZWRfXxLTChYuUuuiN ykC/HUUr5OpT29x6zS6WN5jW2ctw9Izc0ENYjDi7YFBG5R6PK5uibAH80F+lQ3VDf5PeoTUtu6W OsoOdVhDIIBc00KolMHp06krGNgxxM33VWZF9m4CLAZ62EUn8ct2lvRipiu2viFK8POpytTQR0F e1hxFIlcyHvI8Od+dGjzYAuxg4/6kkm+WINohGqDVXYApvxfHjnf8L1bnhPOJgQ/qee6/t/k0WE xNHBqHUkIrWGWjItJNAypdC8htdwlrqsiOwOkLm016PSZVQ2ZY3u21RLAupq5gHBIAJl6pWas= X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.7,FMLib:17.12.80.40 definitions=2025-07-10_02,2025-07-09_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 bulkscore=0 phishscore=0 mlxlogscore=999 malwarescore=0 suspectscore=0 clxscore=1015 adultscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.22.0-2506270000 definitions=main-2507100102 From: Zijun Hu For miscdevice who wants dynamic minor, add a cast to test if it can be successfully registered again without reinitialization: 1) Provide Both miscdevice @dev_A and @dev_B want to request dynamic minor by initializing their minor to MISC_DYNAMIC_MINOR. 2) Register then de-register @dev_A. 3) Register @dev_B. 4) Register @dev_A again without reinitialization. 5) Check if @dev_A can be successfully registered. Signed-off-by: Zijun Hu --- drivers/char/misc_minor_kunit.c | 44 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/drivers/char/misc_minor_kunit.c b/drivers/char/misc_minor_kunit.c index 3184f383bea8c77cbca69ff5e315ea5de2d5512e..6fc8b05169c5754b96588088471a844a2e2ee29b 100644 --- a/drivers/char/misc_minor_kunit.c +++ b/drivers/char/misc_minor_kunit.c @@ -602,6 +602,49 @@ static void miscdev_test_invalid_input(struct kunit *test) misc_deregister(&misc_test); } +/* + * Verify if @miscdyn_a can still be registered successfully without + * reinitialization even if its minor ever owned was requested by + * another miscdevice such as @miscdyn_b. + */ +static void miscdev_test_dynamic_reentry(struct kunit *test) +{ + struct miscdevice miscdyn_a = { + .name = "miscdyn_a", + .minor = MISC_DYNAMIC_MINOR, + .fops = &miscdev_test_fops, + }; + struct miscdevice miscdyn_b = { + .name = "miscdyn_b", + .minor = MISC_DYNAMIC_MINOR, + .fops = &miscdev_test_fops, + }; + int ret, minor_a; + + ret = misc_register(&miscdyn_a); + KUNIT_ASSERT_EQ(test, ret, 0); + KUNIT_EXPECT_TRUE(test, is_valid_dynamic_minor(miscdyn_a.minor)); + minor_a = miscdyn_a.minor; + if (ret != 0) + return; + misc_deregister(&miscdyn_a); + + ret = misc_register(&miscdyn_b); + KUNIT_ASSERT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, miscdyn_b.minor, minor_a); + if (ret != 0) + return; + + ret = misc_register(&miscdyn_a); + KUNIT_ASSERT_EQ(test, ret, 0); + KUNIT_EXPECT_TRUE(test, is_valid_dynamic_minor(miscdyn_a.minor)); + KUNIT_EXPECT_NE(test, miscdyn_a.minor, miscdyn_b.minor); + if (ret == 0) + misc_deregister(&miscdyn_a); + + misc_deregister(&miscdyn_b); +} + static struct kunit_case test_cases[] = { KUNIT_CASE(kunit_static_minor), KUNIT_CASE(kunit_misc_dynamic_minor), @@ -611,6 +654,7 @@ static struct kunit_case test_cases[] = { KUNIT_CASE(miscdev_test_duplicate_name), KUNIT_CASE(miscdev_test_duplicate_name_leak), KUNIT_CASE_PARAM(miscdev_test_duplicate_error, miscdev_gen_params), + KUNIT_CASE(miscdev_test_dynamic_reentry), {} }; -- 2.34.1