From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 476E43D8103 for ; Sun, 18 Oct 2026 03:58:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792295903; cv=none; b=IvL+rz+BFqtW94qptK5SnKnq7GcJBsVeRu3NOfPmWOEmH+dAJmJuiO2wsil/V/P4u//hw3GK/a8yOgNV7vC7wGbE+GiT72vRYi6E21c76JyCbWVzPH/eOFuDDpqZN/mxxTvJMfdoDmeEry89UavBWQR2fc82WUV2yhMVh6QpuyQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792295903; c=relaxed/simple; bh=GM+XiDOwJPZdj+FGQqQAeabioh9lH6r8987v0spWB+I=; h=Message-ID:From:Subject:To:Cc:In-Reply-To:References:Content-Type: Date; b=X989wbULWosAp5flBHphhEmcsQmHibOIL4aRp7ttHm/NcmTFr4zdkw59oyiwItw3NS3E6c4Zx8KVWk4jR8YgnGaMG0Kts9oPM4rkmfo4pqVcsPU9UjP+P6ooMwWBtW3h9BS17WeZ2HR0a9Eeh67nOVz3xWh7qlG3qEbtm/VHV44= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L74GQZWV; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="L74GQZWV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08B821F000C4; Sun, 18 Oct 2026 03:58:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792295899; bh=Y0Njjj8laW760r60BZYUGDDvUluzXejtmasv46TjdO8=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=L74GQZWVu5hkIS2ktmSxJsdsh9DvJ3tu4LR/fmk0M20vz2LTZjYhDcAsNvr/aOlsR pzg/pcwVxtXMLyQILCpdkLW5SRUFf1+z4csmCnjRHo70xR0UKf4awxbogfCbXMPtsO Fvry6GOhKaTHkAN4HK6U4nWH2e8YVBR+ddnGjlTir4ii0BRgWwOF5iHTr3aidnpKf7 SC7d8shRJ4T2fSpJWj9lBXJr8MitJJZTpaHToRXecavr+7pe/+NSY8YzSBjkVl3V/p ePciiVry/qJ4SrwJ9tixo3U+8mMeuBlMZ9OhMB3bjnAO+fh8iaSTsU40VHraK3Rf/x 1k9l/z6y6kuiQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH] rtc: mt7622: allocate the RTC before requesting its IRQ Reply-To: sashiko-reviews@lists.linux.dev To: "Myeonghun Pak" Cc: linux-rtc@vger.kernel.org, "Alexandre Belloni" In-Reply-To: <179229507333.3965554.17726204422948048488.rtc-mt7622-irq-init-order@gmail.com> References: <179229507333.3965554.17726204422948048488.rtc-mt7622-irq-init-order@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sun, 18 Oct 2026 03:58:18 +0000 Precedence: bulk X-Mailing-List: linux-rtc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [Medium] rtc: mt7622: clk disabled in mtk_rtc_remove() before devres tear= down -- commit aaf543ae0f6d2f3fb8f602ad5f4977facde6059e Author: Myeonghun Pak rtc: mt7622: allocate the RTC before requesting its IRQ This patch reorders RTC allocation, hardware initialization, IRQ request, and RTC registration in mtk_rtc_probe() so that devres unregisters the RTC and frees its IRQ before dropping the final RTC device reference. > diff --git a/drivers/rtc/rtc-mt7622.c b/drivers/rtc/rtc-mt7622.c > index 9e17dd09d5673..c86c8cf3f2d77 100644 > --- a/drivers/rtc/rtc-mt7622.c > +++ b/drivers/rtc/rtc-mt7622.c > @@ -324,12 +324,21 @@ static int mtk_rtc_probe(struct platform_device *pd= ev) > if (ret) > return ret; > =20 > + hw->rtc =3D devm_rtc_allocate_device(&pdev->dev); > + if (IS_ERR(hw->rtc)) { > + ret =3D PTR_ERR(hw->rtc); > + goto err; > + } > + > hw->irq =3D platform_get_irq(pdev, 0); > if (hw->irq < 0) { > ret =3D hw->irq; > goto err; > } > =20 > + mtk_rtc_hw_init(hw); > + hw->rtc->ops =3D &mtk_rtc_ops; > + > ret =3D devm_request_irq(&pdev->dev, hw->irq, mtk_rtc_alarmirq, > 0, dev_name(&pdev->dev), hw); > if (ret) { > @@ -337,14 +346,10 @@ static int mtk_rtc_probe(struct platform_device *pd= ev) > goto err; > } > =20 > - mtk_rtc_hw_init(hw); > - > device_init_wakeup(&pdev->dev, true); > =20 > - hw->rtc =3D devm_rtc_device_register(&pdev->dev, pdev->name, > - &mtk_rtc_ops, THIS_MODULE); > - if (IS_ERR(hw->rtc)) { > - ret =3D PTR_ERR(hw->rtc); > + ret =3D devm_rtc_register_device(hw->rtc); > + if (ret) { > dev_err(&pdev->dev, "Unable to register device\n"); > goto err; > } [Severity: Medium] While this fixes the devres ordering between hw->rtc and hw->irq, what about hw->clk during detach? In mtk_rtc_probe(), hw->clk is enabled manually before the devm calls: drivers/rtc/rtc-mt7622.c:mtk_rtc_probe() { ... ret =3D clk_prepare_enable(hw->clk); if (ret) return ret; hw->rtc =3D devm_rtc_allocate_device(&pdev->dev); ... } And it is disabled in mtk_rtc_remove(): drivers/rtc/rtc-mt7622.c:mtk_rtc_remove() { struct mtk_rtc *hw =3D platform_get_drvdata(pdev); clk_disable_unprepare(hw->clk); } During driver unbind or module unload, __device_release_driver() calls device_remove() -> mtk_rtc_remove() before device_unbind_cleanup() calls devres_release_all(). Because hw->rtc and hw->irq are cleaned up by devres, clk_disable_unprepare(hw->clk) runs while hw->rtc is still registered and mtk_rtc_alarmirq() is still active. If an alarm interrupt fires or an mtk_rtc_ops callback runs in that window, mtk_rtc_alarmirq() or the RTC operations will access hw->base MMIO registers after hw->clk has already been disabled: drivers/rtc/rtc-mt7622.c:mtk_rtc_alarmirq() { struct mtk_rtc *hw =3D (struct mtk_rtc *)id; u32 irq_sta; irq_sta =3D mtk_r32(hw, MTK_RTC_INT); ... } Should mtk_rtc_probe() use devm_clk_get_enabled() (and drop mtk_rtc_remove()) so that hw->clk stays enabled until after devres unregisters hw->rtc and frees hw->irq? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/179229507333.396555= 4.17726204422948048488.rtc-mt7622-irq-init-order@gmail.com?part=3D1