From nobody Wed Dec 17 13:55:41 2025 Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) (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 8A17523F422 for ; Mon, 17 Mar 2025 14:00:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.60.130.6 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742220005; cv=none; b=Qvk273wswINO3BYMARS4Ycm0nxrdX82zfdbPTWUuCI87XDgl3Rt4bNqd7y9aD1fk3kiQU2Aeo0ciWzjfgSrSaJff3NXmcM8y/fJfklv/1zNYroWLkm7yfTblAneWMLgCczPtPttXVm2AUhNGkibcMO9n/DnmaKbMbAN+qW8iS/Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742220005; c=relaxed/simple; bh=ymyjoRPJMcdgvc0kCRsHYHBbOg2KFPig2f5PgqMCl+E=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=AwEBqNvpDrrGRUNO8mLcyZOyaSKu27xxA9CSJIP7Sjmf4PMxtrfFYUh6i9f4F7bljcVM4mktF+W/KHcSk57VHK6CTg0NQ94Nz7k+NHLoe3fmAzE+xACPUT0hHRCgrPPk4fqUtXA7IArptdZbTPWKqrW3zlrca/mU+kRXoGUB0IM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=hKbHApAq; arc=none smtp.client-ip=178.60.130.6 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="hKbHApAq" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Cc:To:Message-Id:Content-Transfer-Encoding:Content-Type: MIME-Version:Subject:Date:From:Sender:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=uejaEzJgm4AKmoazWPbdXJYFspuSptSDKXB+HI9ayM0=; b=hKbHApAqWuu7jFRF/VJSzV2WNz 2aPgcNOPaMLYjeDai8XTbuEqs592BlukVvCavhUnaQI4hQ6EBJu3qpZv+9+8yaTrf8ym7nVJJLJ5m 92Dnx9tKAtJSrK9Nv6BpEMUCN2ZNWpFbq9Zzwdsq2z1+crECa2LHpTTZHfKQSNqtux1I73pCOA1qT FlwR2TA5cXspyo3q4jWbOc8aT5Dc5z4O989O2//LYNfIAq6qd2zsY8XzXpFt1QiJXNOMlLfZ34UBw j2mBdzLENFUkNKCUjcIlcItDLBQwEv5TFTGi6poKfAObXo/9bJH/wUaJwroPkbERjEZfHXSSV/f/U nLLRJNfg==; Received: from 179-125-64-250-dinamico.pombonet.net.br ([179.125.64.250] helo=[192.168.67.187]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1tuB0S-002FgL-Df; Mon, 17 Mar 2025 14:59:52 +0100 From: Thadeu Lima de Souza Cascardo Date: Mon, 17 Mar 2025 10:59:55 -0300 Subject: [PATCH] char: misc: register chrdev region with all possible minors 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: quoted-printable Message-Id: <20250317-misc-chrdev-v1-1-6cd05da11aef@igalia.com> X-B4-Tracking: v=1; b=H4sIANoq2GcC/6tWKk4tykwtVrJSqFYqSi3LLM7MzwNyDHUUlJIzE vPSU3UzU4B8JSMDI1MDY0Nz3dzM4mTd5IyilNQy3SQjsyRTc6NEE/O0ZCWgjoKi1LTMCrBp0bG 1tQC4FUrSXQAAAA== X-Change-ID: 20250317-misc-chrdev-b26b572a47fc To: Arnd Bergmann , Greg Kroah-Hartman , D Scott Phillips Cc: linux-kernel@vger.kernel.org, kernel-dev@igalia.com, kernel test robot , Thadeu Lima de Souza Cascardo X-Mailer: b4 0.14.2 register_chrdev will only register the first 256 minors of a major chrdev. That means that dynamically allocated misc devices with minor above 255 will fail to open with -ENXIO. This was found by kernel test robot when testing a different change that makes all dynamically allocated minors be above 255. This has, however, been separately tested by creating 256 serio_raw devices with the help of userio driver. Ever since allowing misc devices with minors above 128, this has been possible. Fix it by registering all minor numbers from 0 to MINORMASK + 1 for MISC_MAJOR. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202503171507.6c8093d0-lkp@intel.com Fixes: ab760791c0cf ("char: misc: Increase the maximum number of dynamic mi= sc devices to 1048448") Signed-off-by: Thadeu Lima de Souza Cascardo Tested-by: Hou Wenlong --- drivers/char/misc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/misc.c b/drivers/char/misc.c index f7dd455dd0dd3c7c9956e772b5ab8bd83a67a4a6..dda466f9181acf76564b5e41ed6= e858928e56182 100644 --- a/drivers/char/misc.c +++ b/drivers/char/misc.c @@ -315,7 +315,7 @@ static int __init misc_init(void) goto fail_remove; =20 err =3D -EIO; - if (register_chrdev(MISC_MAJOR, "misc", &misc_fops)) + if (__register_chrdev(MISC_MAJOR, 0, MINORMASK + 1, "misc", &misc_fops)) goto fail_printk; return 0; =20 --- base-commit: 2dc25093218f5d42391549de6fe45e1aa9325676 change-id: 20250317-misc-chrdev-b26b572a47fc Best regards, --=20 Thadeu Lima de Souza Cascardo