From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 37B053E9C2D; Tue, 12 May 2026 17:47:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778608045; cv=none; b=MzQpTpodanW6+lkdH3t/ihWsYq7Y9cN5cncKDm+Lip+cs6Tv2gh7W2ld5A6ljZ8wG+N+bSBBomo5O6YLJfaio5yLfLqxFnUHAIi81RUfQwDYwie/g/3QXSsVnGiVI8xgKM3jcoJq4uWMrqrZUdaVxghcHAn5NQKZyx9k+1DObDM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778608045; c=relaxed/simple; bh=JmKbMO010C53vdcGDZS9AYbIxBVOdoiN4Wijl4ahHmA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mU/y5XZiqoNWCNYrxwAYPMxfdqgJniDlWEpY/xRV4LhF7Un9fA18tL/Ul7AxKrygTY3ebZSovYa+QeZQEzGIGNiw287/9fmmutF/0mvoOPc4HWsgG67j0B5ZUksDwGbjFGicsAmmtuM1ufKApHc6Or+opaJa5ZDSKl3jhbI0/WY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2B535dMF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="2B535dMF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A8B0C4AF17; Tue, 12 May 2026 17:47:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778608045; bh=JmKbMO010C53vdcGDZS9AYbIxBVOdoiN4Wijl4ahHmA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2B535dMFMZbDVxiwGT8DiimvZEXhRtGTrQGekKalRArdTNdpd2FtlgBX6dAy2miHd r4eqEoEHK8LQp8M3KH1a7mQjWSi1xGXPBSXFQ8DOjVhrhlF9ZTM6mmybPEoNkU9Am8 Wod9JVETCH1MYUIc6A4QiKym+nHrJU2H8ZU+NTCc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Geert Uytterhoeven , Geert Uytterhoeven , Ulf Hansson Subject: [PATCH 6.12 133/206] pmdomain: core: Fix detach procedure for virtual devices in genpd Date: Tue, 12 May 2026 19:39:45 +0200 Message-ID: <20260512173935.674798322@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260512173932.810559588@linuxfoundation.org> References: <20260512173932.810559588@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ulf Hansson commit 26735dfdd8930d9ef1fa92e590a9bf77726efdf6 upstream. If a device is attached to a PM domain through genpd_dev_pm_attach_by_id(), genpd calls pm_runtime_enable() for the corresponding virtual device that it registers. While this avoids boilerplate code in drivers, there is no corresponding call to pm_runtime_disable() in genpd_dev_pm_detach(). This means these virtual devices are typically detached from its genpd, while runtime PM remains enabled for them, which is not how things are designed to work. In worst cases it may lead to critical errors, like a NULL pointer dereference bug in genpd_runtime_suspend(), which was recently reported. For another case, we may end up keeping an unnecessary vote for a performance state for the device. To fix these problems, let's add this missing call to pm_runtime_disable() in genpd_dev_pm_detach(). Reported-by: Geert Uytterhoeven Closes: https://lore.kernel.org/all/CAMuHMdWapT40hV3c+CSBqFOW05aWcV1a6v_NiJYgoYi0i9_PDQ@mail.gmail.com/ Fixes: 3c095f32a92b ("PM / Domains: Add support for multi PM domains per device to genpd") Cc: stable@vger.kernel.org Tested-by: Geert Uytterhoeven Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- drivers/pmdomain/core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/drivers/pmdomain/core.c +++ b/drivers/pmdomain/core.c @@ -2900,6 +2900,7 @@ static const struct bus_type genpd_bus_t static void genpd_dev_pm_detach(struct device *dev, bool power_off) { struct generic_pm_domain *pd; + bool is_virt_dev; unsigned int i; int ret = 0; @@ -2909,6 +2910,13 @@ static void genpd_dev_pm_detach(struct d dev_dbg(dev, "removing from PM domain %s\n", pd->name); + /* Check if the device was created by genpd at attach. */ + is_virt_dev = dev->bus == &genpd_bus_type; + + /* Disable runtime PM if we enabled it at attach. */ + if (is_virt_dev) + pm_runtime_disable(dev); + /* Drop the default performance state */ if (dev_gpd_data(dev)->default_pstate) { dev_pm_genpd_set_performance_state(dev, 0); @@ -2934,7 +2942,7 @@ static void genpd_dev_pm_detach(struct d genpd_queue_power_off_work(pd); /* Unregister the device if it was created by genpd. */ - if (dev->bus == &genpd_bus_type) + if (is_virt_dev) device_unregister(dev); }