From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outbound.pv.icloud.com (p-west1-cluster4-host12-snip4-9.eps.apple.com [57.103.65.230]) (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 ABAB7303DD9 for ; Fri, 4 Jul 2025 13:28:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=57.103.65.230 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751635725; cv=none; b=TLJpwIT8QzPaucr4VF5/XTR/9NL76Sftjs09pwExahWO+x29P0GgTrUXs/omKqb+whPPdYjMc7FPEUTb2dquR+m4NiyFybA9qwFuxPbQIR79P8OuCtcoOP2SUd3mc/BB1Di1FNNc2fBveKdIur5WMwZyuGEs2v4t8otDcelfV/g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751635725; c=relaxed/simple; bh=wFGpDXTdZuxmwa4jC4AUegIxrdfaKn8pxUX8kuIpn9E=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=DihBNm4cWk9m5TDL+k9w0wnJpXzYuywvz3D2yWkcRXQ6NpBzFlidewk6IXnx7EIGWmEKSsvpG/jY6gL/GUVaXlHCryTxKrUKI4NswJ1ei18JrX25iGIj2488c5J9r0OqYh8+xqQmoMQdJGPf8fVYF+14UBkKRHOIkQLckslvvp4= 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=HnaJ8NMF; arc=none smtp.client-ip=57.103.65.230 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="HnaJ8NMF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=icloud.com; s=1a1hai; bh=cbt7c0HlAVhmp4PCZp8Pa4hR5RztlzTvRA5ww/nditw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:x-icloud-hme; b=HnaJ8NMFc+VYP8r8T45TLZ26zDaZABJAjuodrG76GA7NI2k+1Td7z3TTS/C3YDwbu pu7snHzh1TAdUEN4ng1o9X4mQrU6zoL0F1gupisz56KkIgC6o/St5ZvvpePSHQD5Mt AdbqjhvEl0JaNxOUT8qhcLpi7U7efSSWxDfsMqYHd1sgmBVyk549UiP2mwqzPsjGwe ZYCJcOl3RMnZpfe0M3K9uzJlw3a5cJyL0Dcnx+LG5yj9HSCcZEZiLXKkj/pdpQdurL ou9hPFaW2Slmia2ODgmpseQZA5H3YcAPjtbV3qEY6qujdj5smm6x3X/MFy/+4F0hzu sCHvI7p1R/2zg== Received: from outbound.pv.icloud.com (unknown [127.0.0.2]) by outbound.pv.icloud.com (Postfix) with ESMTPS id 4E0231800F94; Fri, 4 Jul 2025 13:28:40 +0000 (UTC) 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 E90831803C44; Fri, 4 Jul 2025 13:26:30 +0000 (UTC) From: Zijun Hu Date: Fri, 04 Jul 2025 21:26:03 +0800 Subject: [PATCH v4 5/8] char: misc: Make registering miscdevice reentry who wants dynamic minor Precedence: bulk X-Mailing-List: linux-kernel@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: <20250704-rfc_miscdev-v4-5-b48986112d6a@oss.qualcomm.com> References: <20250704-rfc_miscdev-v4-0-b48986112d6a@oss.qualcomm.com> In-Reply-To: <20250704-rfc_miscdev-v4-0-b48986112d6a@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: a-iVs9U9UV9OuytPZirYj8aUJKBqtP1R X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzA0MDEwMiBTYWx0ZWRfXz5X44wgqsz15 kXv3nVARY7F98D+c79RT7+0/U6ZbuI8msh/lqisV0bgxrSJTCz5BpaoLueYw1pEolUEhMok4UN2 NVS3CdvhH+fFB2C/mBD5oXJZi2OQumXN9T48SvueUKVKNAlV5xzDKdl11HqOH2OwX/2SZJMWj3Q iyPWsqtu7IefFk4nh8QhxZzpucOUjP4P/Zqykwe197whrhjRbcO/VJQ8BxQs/IX95/AHX0Cn/oO D8Gw/zNEYGoEuzFYiHCVLDvUJN9iODgxDvfJdZOTC4rB7509VrFiS0CM2vs42l6k+dn7woPLY= X-Proofpoint-ORIG-GUID: a-iVs9U9UV9OuytPZirYj8aUJKBqtP1R 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=2025-07-04_05,2025-07-04_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 adultscore=0 suspectscore=0 malwarescore=0 clxscore=1015 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.22.0-2506060001 definitions=main-2507040102 From: Zijun Hu misc_deregister() frees dynamic minor @misc->minor but does not reset it and cause kunit test case miscdev_test_dynamic_reentry() failure: | Invalid fixed minor 257 for miscdevice 'miscdyn_a' | #miscdev_test_dynamic_reentry: ASSERTION FAILED at misc_minor_kunit.c:639 | Expected ret == 0, but | ret == -22 (0xffffffffffffffea) | [FAILED] miscdev_test_dynamic_reentry misc_register()/misc_deregister() are sometimes invoked by driver's probe()/remove() separately, which has reentry requirement. Fix by resetting @misc->minor to MISC_DYNAMIC_MINOR in misc_deregister() as error handling of misc_register() does. Signed-off-by: Zijun Hu --- drivers/char/misc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/char/misc.c b/drivers/char/misc.c index b8e66466184fa21fb66d968db7950e0b5669ac43..96ed343cf5c8509a09855020049a9af82a3ede95 100644 --- a/drivers/char/misc.c +++ b/drivers/char/misc.c @@ -288,6 +288,8 @@ void misc_deregister(struct miscdevice *misc) list_del(&misc->list); device_destroy(&misc_class, MKDEV(MISC_MAJOR, misc->minor)); misc_minor_free(misc->minor); + if (misc->minor > MISC_DYNAMIC_MINOR) + misc->minor = MISC_DYNAMIC_MINOR; mutex_unlock(&misc_mtx); } EXPORT_SYMBOL(misc_deregister); -- 2.34.1