From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx-relay27-hz2.antispameurope.com (mx-relay27-hz2.antispameurope.com [94.100.136.227]) (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 D2C8C23EAA3 for ; Wed, 11 Feb 2026 14:45:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=94.100.136.227 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770821108; cv=pass; b=gOPbGg3IgjgQ2qJ7CwzTHdiaeCLLmXU6VsZgQU4UgpJxFuRX3Hz107KXDhK3ZMHi1b3+wVw2wiBqSAfUSTB5nyD/MqVArO7DvlfkUxFm85FG9GfqkEchV3spmIu9qHcme0ZUosXxk7IE4Nmt5rwKV9KeUgkOjzMVU4HTtekBvVQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770821108; c=relaxed/simple; bh=hCi194bm0NWmpJWCGJmmjhLbLsw6bP5FZChrljeU0to=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=TfHP05UEDPPhXOe9NeVAtF1x8HHR2vyWgV1QkIQJDPhtw6yRXXVT9CcFH5bhxja9nt29i8gWWUmgG3nPpDtCTr6rRQ7tHpcuFxa/HsWRnAEX/3PIWPPlXFu5o9e+bkHZSVyDMSnBfgMQIJ3I6KTqGzwyC+5aM+2g1Sj5GGBlKQo= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ew.tq-group.com; spf=pass smtp.mailfrom=ew.tq-group.com; dkim=pass (2048-bit key) header.d=ew.tq-group.com header.i=@ew.tq-group.com header.b=KMtulnC3; arc=pass smtp.client-ip=94.100.136.227 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ew.tq-group.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ew.tq-group.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ew.tq-group.com header.i=@ew.tq-group.com header.b="KMtulnC3" ARC-Authentication-Results: i=1; mx-gate27-hz2.hornetsecurity.com 1; spf=pass reason=mailfrom (ip=94.100.132.6, headerfrom=ew.tq-group.com) smtp.mailfrom=ew.tq-group.com smtp.helo=smtp-out02-hz1.hornetsecurity.com; dmarc=pass header.from=ew.tq-group.com orig.disposition=pass ARC-Message-Signature: a=rsa-sha256; bh=yYxQt2OGcmdSWshE3/Ad5apdbgodHOqiD6B7wlmUAZ4=; c=relaxed/relaxed; d=hornetsecurity.com; h=from:to:date:subject:mime-version:; i=1; s=hse1; t=1770821030; b=dHL0g0i6LDiiaOJNT75HcLvQcFS03HgPMIN4bvyDGxU4hrHWwGoBo9Zb5B/9gIFz7plSpkMi 1HFgXG4FXWFH0nyIx0wCvTSOM/8I+/QSXvrH+sfCbQ2cCytgQgniR5XvXcR8UoX+qIXWn0Bd39Z Dg2c9k/t2I7GQw9D6Bq/XFqxJh76dhNqNbHuqQoJ09B7ds1xTo8IdYc5as1qPJpxcp59iRP5EPM 1tgrbHSc8OeT1dUEeJwz4BhhQSwbtI79bPZZU4u2uzqngnb5Q4RiOdZhctAQGV+W5dOxBMHW/yT KHmX3Tzi6wtD5Z1nGzHUZuZaK/elufmbKhQ8YUtsRCLBQ== ARC-Seal: a=rsa-sha256; cv=none; d=hornetsecurity.com; i=1; s=hse1; t=1770821030; b=FAX9QFOo16kgqlse9LssVv39rkBZThWjSSuMbBkNuqEMQBETA06JQ2Y0S8BFU4oIMBSBV1NV 1GnkWawjQzKpIJFWJgAMdJ3BoztCMYSYisiuJ5i/heDbgwM5hlDo8EIGLkf9kxj/CENAultXkUh 1GWUHiBGuWuki9z4/6+3FNXvmKiAgYXRhCtMA01KdV+SUBpMVfPHpGrXfj1vK6iwHgofyamNzEA 6pY8YXL1pkmpSHDRMPLD8fjfHt8txs59SmChcyjrz4BI1b+/MKu4WEnH7mSPPYlAYjCBdhTJ3BN dOLCJ7En5lImHCmj5ZPK3RZwfQ0WLkpCanXX3J1zhfXEQ== Received: from he-nlb01-hz1.hornetsecurity.com ([94.100.132.6]) by mx-relay27-hz2.antispameurope.com; Wed, 11 Feb 2026 15:43:50 +0100 Received: from steina-w.localnet (host-82-135-125-110.customer.m-online.net [82.135.125.110]) (Authenticated sender: alexander.stein@ew.tq-group.com) by smtp-out02-hz1.hornetsecurity.com (Postfix) with ESMTPSA id 7AD175A12E1; Wed, 11 Feb 2026 15:43:34 +0100 (CET) From: Alexander Stein To: abelvesa@kernel.org, peng.fan@nxp.com, mturquette@baylibre.com, sboyd@kernel.org, Frank.Li@nxp.com, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, gregkh@linuxfoundation.org, rafael@kernel.org, hanguidong02@gmail.com, Danilo Krummrich Cc: driver-core@lists.linux.dev, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Danilo Krummrich Subject: Re: [PATCH] clk: scu/imx8qxp: do not register driver in probe() Date: Wed, 11 Feb 2026 15:43:34 +0100 Message-ID: <10809444.nUPlyArG6x@steina-w> Organization: TQ-Systems GmbH In-Reply-To: <20260211142321.55404-1-dakr@kernel.org> References: <20260211142321.55404-1-dakr@kernel.org> Precedence: bulk X-Mailing-List: imx@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" X-cloud-security-sender:alexander.stein@ew.tq-group.com X-cloud-security-recipient:imx@lists.linux.dev X-cloud-security-crypt: load encryption module X-cloud-security-Mailarchiv: E-Mail archived for: alexander.stein@ew.tq-group.com X-cloud-security-Mailarchivtype:outbound X-cloud-security-Virusscan:CLEAN X-cloud-security-disclaimer: This E-Mail was scanned by E-Mailservice on mx-relay27-hz2.antispameurope.com with 4fB1QH3NLmz2Nm8r X-cloud-security-connect: he-nlb01-hz1.hornetsecurity.com[94.100.132.6], TLS=1, IP=94.100.132.6 X-cloud-security-Digest:8e7c20d949661fe4b3ede5b8a28db6ab X-cloud-security:scantime:2.326 DKIM-Signature: a=rsa-sha256; bh=yYxQt2OGcmdSWshE3/Ad5apdbgodHOqiD6B7wlmUAZ4=; c=relaxed/relaxed; d=ew.tq-group.com; h=content-type:mime-version:subject:from:to:message-id:date; s=hse1; t=1770821030; v=1; b=KMtulnC3vAH01rEBw7emFGewSxpCQJKcllBWP8XuEefHbF4wxQFVW/SZ8T3jvLvQQdKHB+8Q 5yuhMnzCSEGKIqH74zUoKFIUGFxVfo9cQT6iFanls7VFENttsDWGMBVVhCOfp0CSoDh+mKfqVN/ sq1fuNJtTdltMvM4OqUKpMCXFyE0730lOvEHMWrFuFfLRohihBGG7VEonNuXKNTBNqTI23nEDKY uea7f3bb9L5SjXMNeT2e1skMhtKhpbQp2tJpFWEiawYJW3IVSJSv4ugsDewJcqDGN+aRt2f+UeY gYFAFFarqpcNsgGI/sqFOMTzzA4pdX/Ch498pyKxRZi8w== Hi Danilo, Am Mittwoch, 11. Februar 2026, 15:23:16 CET schrieb Danilo Krummrich: > imx_clk_scu_init() registers the imx_clk_scu_driver while commonly being > called from IMX driver's probe() callbacks. >=20 > However, it neither makes sense to register drivers from probe() > callbacks of other drivers, nor does the driver core allow registering > drivers with a device lock already being held. >=20 > The latter was revealed by commit dc23806a7c47 ("driver core: enforce > device_lock for driver_match_device()") leading to a deadlock condition > described in [1]. >=20 > Additionally, nothing seems to unregister the imx_clk_scu_driver once > the corresponding driver module is unloaded, which leaves the > driver-core with a dangling pointer. >=20 > Hence, register the imx_clk_scu_driver from module_init() and unregister > it in module_exit(). >=20 > Fixes: dc23806a7c47 ("driver core: enforce device_lock for driver_match_d= evice()") > Fixes: 220175cd3979 ("clk: imx: scu: fix build break when compiled as mod= ules") > Reported-by: Alexander Stein > Closes: https://lore.kernel.org/lkml/13955113.uLZWGnKmhe@steina-w/ > Link: https://lore.kernel.org/lkml/DFU7CEPUSG9A.1KKGVW4HIPMSH@kernel.org/= [1] > Signed-off-by: Danilo Krummrich Thanks for the patch. Tested-by: Alexander Stein # TQMa8x/MBa8x > --- > I plan to send the driver-core PR for 7.0-rc1 soon, which will also conta= in > commit dc23806a7c47 ("driver core: enforce device_lock for > driver_match_device()"). >=20 > It also contains an IOMMU commit similar to this one: > https://patch.msgid.link/20260121141215.29658-1-dakr@kernel.org >=20 > The commit was originally scheduled for 6.19-rc7, but was deferred to 7.0= =2Drc1 in > case more of those cases pop up (which now happened). > --- > drivers/clk/imx/clk-imx8qxp.c | 24 +++++++++++++++++++++++- > drivers/clk/imx/clk-scu.c | 12 +++++++++++- > drivers/clk/imx/clk-scu.h | 2 ++ > 3 files changed, 36 insertions(+), 2 deletions(-) >=20 > diff --git a/drivers/clk/imx/clk-imx8qxp.c b/drivers/clk/imx/clk-imx8qxp.c > index 3ae162625bb1..d89a2f40771e 100644 > --- a/drivers/clk/imx/clk-imx8qxp.c > +++ b/drivers/clk/imx/clk-imx8qxp.c > @@ -346,7 +346,29 @@ static struct platform_driver imx8qxp_clk_driver =3D= { > }, > .probe =3D imx8qxp_clk_probe, > }; > -module_platform_driver(imx8qxp_clk_driver); > + > +static int __init imx8qxp_init(void) > +{ > + int ret; > + > + ret =3D platform_driver_register(&imx8qxp_clk_driver); > + if (ret) > + return ret; > + > + ret =3D imx_clk_scu_module_init(); > + if (ret) > + platform_driver_unregister(&imx8qxp_clk_driver); > + > + return ret; > +} > +module_init(imx8qxp_init); > + > +static void __exit imx8qxp_exit(void) > +{ > + imx_clk_scu_module_exit(); > + platform_driver_unregister(&imx8qxp_clk_driver); > +} > +module_exit(imx8qxp_exit); > =20 > MODULE_AUTHOR("Aisheng Dong "); > MODULE_DESCRIPTION("NXP i.MX8QXP clock driver"); > diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c > index 34c9dc1fb20e..c90d21e05f91 100644 > --- a/drivers/clk/imx/clk-scu.c > +++ b/drivers/clk/imx/clk-scu.c > @@ -191,6 +191,16 @@ static bool imx_scu_clk_is_valid(u32 rsrc_id) > return p !=3D NULL; > } > =20 > +int __init imx_clk_scu_module_init(void) > +{ > + return platform_driver_register(&imx_clk_scu_driver); > +} > + > +void __exit imx_clk_scu_module_exit(void) > +{ > + return platform_driver_unregister(&imx_clk_scu_driver); > +} > + > int imx_clk_scu_init(struct device_node *np, > const struct imx_clk_scu_rsrc_table *data) > { > @@ -215,7 +225,7 @@ int imx_clk_scu_init(struct device_node *np, > rsrc_table =3D data; > } > =20 > - return platform_driver_register(&imx_clk_scu_driver); > + return 0; > } > =20 > /* > diff --git a/drivers/clk/imx/clk-scu.h b/drivers/clk/imx/clk-scu.h > index af7b697f51ca..ca82f2cce897 100644 > --- a/drivers/clk/imx/clk-scu.h > +++ b/drivers/clk/imx/clk-scu.h > @@ -25,6 +25,8 @@ extern const struct imx_clk_scu_rsrc_table imx_clk_scu_= rsrc_imx8dxl; > extern const struct imx_clk_scu_rsrc_table imx_clk_scu_rsrc_imx8qxp; > extern const struct imx_clk_scu_rsrc_table imx_clk_scu_rsrc_imx8qm; > =20 > +int __init imx_clk_scu_module_init(void); > +void __exit imx_clk_scu_module_exit(void); > int imx_clk_scu_init(struct device_node *np, > const struct imx_clk_scu_rsrc_table *data); > struct clk_hw *imx_scu_of_clk_src_get(struct of_phandle_args *clkspec, >=20 > base-commit: 192c0159402e6bfbe13de6f8379546943297783d >=20 =2D-=20 TQ-Systems GmbH | M=FChlstra=DFe 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht M=FCnchen, HRB 105018 Gesch=E4ftsf=FChrer: Detlef Schneider, R=FCdiger Stahl, Stefan Schneider http://www.tq-group.com/