Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752419AbbHaDfn (ORCPT ); Sun, 30 Aug 2015 23:35:43 -0400 Received: from m50-111.126.com ([123.125.50.111]:47046 "EHLO m50-111.126.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751919AbbHaDfm (ORCPT ); Sun, 30 Aug 2015 23:35:42 -0400 From: Xunlei Pang To: "Rafael J. Wysocki" , linux-kernel@vger.kernel.org Cc: Daniel Lezcano , linux-pm@vger.kernel.org, Xunlei Pang Subject: [PATCH v3] cpuidle/coupled: Add sanity check for safe_state_index Date: Mon, 31 Aug 2015 11:34:05 +0800 Message-Id: <1440992045-17464-1-git-send-email-xlpang@126.com> X-Mailer: git-send-email 1.9.1 X-CM-TRANSID: jtKowAAXu6g9y+NV8kKTAg--.21709S3 X-Coremail-Antispam: 1Uf129KBjvJXoWxCr47Jw4xXw48Xw45JrWkZwb_yoW5CF43pF WDW34akr4DJ3yxW3yIy34j9as8ua4vqrWrGrWYka43XFn7tF1Fyan8JFy5Zr4kJry8CF12 qw1DtrnxC3W5KFUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jk8n5UUUUU= X-Originating-IP: [210.21.223.3] X-CM-SenderInfo: p0ost0bj6rjloofrz/1tbi6AVmv1UJSFwI6gABsf Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3224 Lines: 99 From: Xunlei Pang Since we are using cpuidle_driver::safe_state_index directly as the target state index, it is better to add the sanity check at the point of registering the driver. Signed-off-by: Xunlei Pang --- v2->v3: Move the code to a new cpuidle_coupled_state_verify() depending on CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED, to avoid using #ifdef in function bodies. Thanks Rafael's comments on this. drivers/cpuidle/coupled.c | 22 ++++++++++++++++++++++ drivers/cpuidle/cpuidle.h | 6 ++++++ drivers/cpuidle/driver.c | 4 ++++ 3 files changed, 32 insertions(+) diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c index 1523e2d..344058f 100644 --- a/drivers/cpuidle/coupled.c +++ b/drivers/cpuidle/coupled.c @@ -187,6 +187,28 @@ bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state) } /** + * cpuidle_coupled_state_verify - check if the coupled states are correctly set. + * @drv: struct cpuidle_driver for the platform + * + * Returns 0 for valid state values, a negative error code otherwise: + * * -EINVAL if any coupled state(safe_state_index) is wrongly set. + */ +int cpuidle_coupled_state_verify(struct cpuidle_driver *drv) +{ + int i; + + for (i = drv->state_count - 1; i >= 0; i--) { + if (cpuidle_state_is_coupled(drv, i) && + (drv->safe_state_index == i || + drv->safe_state_index < 0 || + drv->safe_state_index >= drv->state_count)) + return -EINVAL; + } + + return 0; +} + +/** * cpuidle_coupled_set_ready - mark a cpu as ready * @coupled: the struct coupled that contains the current cpu */ diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h index 178c5ad..f87f399 100644 --- a/drivers/cpuidle/cpuidle.h +++ b/drivers/cpuidle/cpuidle.h @@ -35,6 +35,7 @@ extern void cpuidle_remove_sysfs(struct cpuidle_device *dev); #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state); +int cpuidle_coupled_state_verify(struct cpuidle_driver *drv); int cpuidle_enter_state_coupled(struct cpuidle_device *dev, struct cpuidle_driver *drv, int next_state); int cpuidle_coupled_register_device(struct cpuidle_device *dev); @@ -46,6 +47,11 @@ bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state) return false; } +static inline int cpuidle_coupled_state_verify(struct cpuidle_driver *drv) +{ + return 0; +} + static inline int cpuidle_enter_state_coupled(struct cpuidle_device *dev, struct cpuidle_driver *drv, int next_state) { diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c index 5db1478..389ade4 100644 --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -227,6 +227,10 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv) if (!drv || !drv->state_count) return -EINVAL; + ret = cpuidle_coupled_state_verify(drv); + if (ret) + return ret; + if (cpuidle_disabled()) return -ENODEV; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/