From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E8BAB3B27F1; Sun, 30 Aug 2026 11:57:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788091068; cv=none; b=GhJHvPSJsadVeEwRlbIhfSOYi0onMNIPdQsHCoOZU18Fm6UXIhRDc/LRlT6tVR48hEO1dfCFn8tpa9N81gWrLu5+cfYvI1iUBbqgVzxfyM4Atv7TiFk8aHVPaijQDteolCPzujfaho+PB7pIhunk4bfqRxG5YrpF1KdvTG4+PB8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788091068; c=relaxed/simple; bh=BQgM1qrPaUWQz/CII0FAe9DlvpehPJgNouZhybA49g0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=QC6wXSSQ3cIKdFP5kfMqMH3lK5Vm4VtfE9Td1wozhuILpJsjIpov5jPg1ciaG6J8prYE3elKJlTfw95ZavyaGN0CS8hazYQ4qAIJ/513zFkweH8tSrDO+DoXMC1ci4CimIwvFLC4ofS+lXDUNxV2FMpfGynxg3WPwoY1Uk5r/e4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=A6BkqB0q; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="A6BkqB0q" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A0F8914BF; Sun, 30 Aug 2026 04:57:42 -0700 (PDT) Received: from e127648.arm.com (unknown [10.57.5.212]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4F6993F66F; Sun, 30 Aug 2026 04:57:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1788091066; bh=BQgM1qrPaUWQz/CII0FAe9DlvpehPJgNouZhybA49g0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A6BkqB0qgiaLhifAJh3VURw9RMSsiLS2gGVLFmrJv4GWNrUS6j6rOzP3JAqJRb+XR wP5NF04pDdkRj5QtiRvjLJo7LK704yzldsUdLXwFqnPxERTRBq90xsof+VqOSYgqKn wlDjCy4TH3a6eMoJXevG6EulOPnTfZz+aQfMbCBI= From: Christian Loehle To: "Rafael J . Wysocki" , Viresh Kumar Cc: linux-pm@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Len Brown , Jie Zhan , Lifeng Zheng , Pierre Gondois , Sumit Gupta , Sudeep Holla , Ionela Voinescu , zhongqiu.han@oss.qualcomm.com, Christian Loehle , Sashiko Subject: [PATCH v6 07/15] ACPI: CPPC: Release CPC descriptors through kobject Date: Sun, 30 Aug 2026 12:56:36 +0100 Message-Id: <20260830115644.2056983-8-christian.loehle@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260830115644.2056983-1-christian.loehle@arm.com> References: <20260830115644.2056983-1-christian.loehle@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The CPC descriptor embeds the kobject used for its sysfs directory, but it has no release callback and processor exit frees the descriptor immediately after kobject_put(). It also unmaps register resources and releases PCC state before sysfs removal has drained active attribute callbacks. Provide a release callback which unmaps and frees the descriptor, and use the same cleanup helper before kobject initialization. Once initialized, let kobject_put() own descriptor cleanup so its error path cannot free the object twice. On processor exit, first unpublish the per-CPU descriptor and remove its sysfs directory, then release PCC state and drop the kobject reference. This keeps all resources valid while sysfs callbacks are active and also works with delayed kobject release. Fixes: 158c998ea44b ("ACPI / CPPC: add sysfs support to compute delivered performance") Reported-by: Sashiko Link: https://sashiko.dev/#/patchset/20260724134251.1632824-1-christian.loehle%40arm.com Signed-off-by: Christian Loehle --- drivers/acpi/cppc_acpi.c | 49 ++++++++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 20 deletions(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index f9866563466b..37ff54a048c9 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -350,7 +350,27 @@ static struct attribute *cppc_attrs[] = { }; ATTRIBUTE_GROUPS(cppc); +static void cppc_free_desc(struct cpc_desc *cpc_ptr) +{ + unsigned int i; + + for (i = 2; i < cpc_ptr->num_entries; i++) { + void __iomem *addr = cpc_ptr->cpc_regs[i - 2].sys_mem_vaddr; + + if (addr) + iounmap(addr); + } + + kfree(cpc_ptr); +} + +static void cppc_kobj_release(struct kobject *kobj) +{ + cppc_free_desc(to_cpc_desc(kobj)); +} + static const struct kobj_type cppc_ktype = { + .release = cppc_kobj_release, .sysfs_ops = &kobj_sysfs_ops, .default_groups = cppc_groups, }; @@ -1147,21 +1167,14 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) if (ret) { per_cpu(cpc_desc_ptr, pr->id) = NULL; kobject_put(&cpc_ptr->kobj); - goto out_free; + goto out_buf_free; } kfree(output.pointer); return 0; out_free: - /* Free all the mapped sys mem areas for this CPU */ - for (i = 2; i < cpc_ptr->num_entries; i++) { - void __iomem *addr = cpc_ptr->cpc_regs[i-2].sys_mem_vaddr; - - if (addr) - iounmap(addr); - } - kfree(cpc_ptr); + cppc_free_desc(cpc_ptr); out_buf_free: if (cpc_present) @@ -1180,10 +1193,14 @@ EXPORT_SYMBOL_GPL(acpi_cppc_processor_probe); void acpi_cppc_processor_exit(struct acpi_processor *pr) { struct cpc_desc *cpc_ptr; - unsigned int i; - void __iomem *addr; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, pr->id); + cpc_ptr = per_cpu(cpc_desc_ptr, pr->id); + if (cpc_ptr) { + per_cpu(cpc_desc_ptr, pr->id) = NULL; + kobject_del(&cpc_ptr->kobj); + } + if (pcc_ss_id >= 0 && pcc_data[pcc_ss_id]) { if (pcc_data[pcc_ss_id]->pcc_channel_acquired) { pcc_data[pcc_ss_id]->refcount--; @@ -1194,20 +1211,12 @@ void acpi_cppc_processor_exit(struct acpi_processor *pr) } } } + per_cpu(cpu_pcc_subspace_idx, pr->id) = -1; - cpc_ptr = per_cpu(cpc_desc_ptr, pr->id); if (!cpc_ptr) return; - /* Free all the mapped sys mem areas for this CPU */ - for (i = 2; i < cpc_ptr->num_entries; i++) { - addr = cpc_ptr->cpc_regs[i-2].sys_mem_vaddr; - if (addr) - iounmap(addr); - } - kobject_put(&cpc_ptr->kobj); - kfree(cpc_ptr); } EXPORT_SYMBOL_GPL(acpi_cppc_processor_exit); -- 2.34.1