From patchwork Mon Jul 6 03:13:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Neal Liu X-Patchwork-Id: 11644845 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0827C13BD for ; Mon, 6 Jul 2020 03:13:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF19F20724 for ; Mon, 6 Jul 2020 03:13:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="IVmYEUN3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728711AbgGFDNf (ORCPT ); Sun, 5 Jul 2020 23:13:35 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:22431 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728709AbgGFDNe (ORCPT ); Sun, 5 Jul 2020 23:13:34 -0400 X-UUID: 961b5db1c8e74aa99f2a2901d7107d2f-20200706 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=pKniBVcACW/1c0nv/+i0UMEccnPGSztmdOgnnm5URG0=; b=IVmYEUN3vmp2vCR+13XeHdnDKPyhhE/A1MhmIXtWqBqo9n7y/LJFMlo1lrJr66e66tiWL5NXk3swUPlOdRxMdnpaUJ7rAlng+92hkbUoiDgjIexlFtPYHV3cD1TC30lk0BBWaYK9O/iZd+ShDjx5cgoaL5SdrkProUBNY4zolkE=; X-UUID: 961b5db1c8e74aa99f2a2901d7107d2f-20200706 Received: from mtkexhb02.mediatek.inc [(172.21.101.103)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0809 with TLS) with ESMTP id 1664098016; Mon, 06 Jul 2020 11:13:29 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs02n2.mediatek.inc (172.21.101.101) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 6 Jul 2020 11:13:16 +0800 Received: from mtkswgap22.mediatek.inc (172.21.77.33) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 6 Jul 2020 11:13:18 +0800 From: Neal Liu To: "Rafael J. Wysocki" , Len Brown , Daniel Lezcano , Thierry Reding , Jonathan Hunter , Jacob Pan , Matthias Brugger , Sami Tolvanen CC: Neal Liu , , , , , , lkml , Subject: [PATCH v2] cpuidle: change enter_s2idle() prototype Date: Mon, 6 Jul 2020 11:13:16 +0800 Message-ID: <1594005196-16327-2-git-send-email-neal.liu@mediatek.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1594005196-16327-1-git-send-email-neal.liu@mediatek.com> References: <1594005196-16327-1-git-send-email-neal.liu@mediatek.com> MIME-Version: 1.0 X-TM-SNTS-SMTP: 597824827A178439AFED3D26CDAD9F180957C939B943E4CAF103919A77FC3B032000:8 X-MTK: N Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Control Flow Integrity(CFI) is a security mechanism that disallows changes to the original control flow graph of a compiled binary, making it significantly harder to perform such attacks. init_state_node() assign same function callback to different function pointer declarations. static int init_state_node(struct cpuidle_state *idle_state, const struct of_device_id *matches, struct device_node *state_node) { ... idle_state->enter = match_id->data; ... idle_state->enter_s2idle = match_id->data; } Function declarations: struct cpuidle_state { ... int (*enter) (struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); void (*enter_s2idle) (struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); }; In this case, either enter() or enter_s2idle() would cause CFI check failed since they use same callee. Align function prototype of enter() since it needs return value for some use cases. The return value of enter_s2idle() is no need currently. Signed-off-by: Neal Liu Reviewed-by: Sami Tolvanen --- drivers/acpi/processor_idle.c | 6 ++++-- drivers/cpuidle/cpuidle-tegra.c | 8 +++++--- drivers/idle/intel_idle.c | 6 ++++-- include/linux/cpuidle.h | 6 +++--- 4 files changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 75534c5..6ffb6c9 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -655,8 +655,8 @@ static int acpi_idle_enter(struct cpuidle_device *dev, return index; } -static void acpi_idle_enter_s2idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) +static int acpi_idle_enter_s2idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) { struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); @@ -674,6 +674,8 @@ static void acpi_idle_enter_s2idle(struct cpuidle_device *dev, } } acpi_idle_do_entry(cx); + + return 0; } static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, diff --git a/drivers/cpuidle/cpuidle-tegra.c b/drivers/cpuidle/cpuidle-tegra.c index 1500458..a12fb14 100644 --- a/drivers/cpuidle/cpuidle-tegra.c +++ b/drivers/cpuidle/cpuidle-tegra.c @@ -253,11 +253,13 @@ static int tegra_cpuidle_enter(struct cpuidle_device *dev, return err ? -1 : index; } -static void tegra114_enter_s2idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index) +static int tegra114_enter_s2idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) { tegra_cpuidle_enter(dev, drv, index); + + return 0; } /* diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index f449584..b178da3 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -175,13 +175,15 @@ static __cpuidle int intel_idle(struct cpuidle_device *dev, * Invoked as a suspend-to-idle callback routine with frozen user space, frozen * scheduler tick and suspended scheduler clock on the target CPU. */ -static __cpuidle void intel_idle_s2idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) +static __cpuidle int intel_idle_s2idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) { unsigned long eax = flg2MWAIT(drv->states[index].flags); unsigned long ecx = 1; /* break on interrupt flag */ mwait_idle_with_hints(eax, ecx); + + return 0; } /* diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index ec2ef63..bee10c0 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -66,9 +66,9 @@ struct cpuidle_state { * suspended, so it must not re-enable interrupts at any point (even * temporarily) or attempt to change states of clock event devices. */ - void (*enter_s2idle) (struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index); + int (*enter_s2idle)(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index); }; /* Idle State Flags */