From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jia-Ju Bai Subject: [PATCH] opp: cpu: Replace GFP_ATOMIC with GFP_KERNEL in dev_pm_opp_init_cpufreq_table Date: Fri, 26 Jan 2018 16:48:49 +0800 Message-ID: <1516956529-32264-1-git-send-email-baijiaju1990@gmail.com> Return-path: Received: from mail-pg0-f67.google.com ([74.125.83.67]:38947 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752336AbeAZIoT (ORCPT ); Fri, 26 Jan 2018 03:44:19 -0500 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: vireshk@kernel.org, nm@ti.com, sboyd@codeaurora.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai After checking all possible call chains to dev_pm_opp_init_cpufreq_table() here, my tool finds that this function is never called in atomic context, namely never in an interrupt handler or holding a spinlock. And dev_pm_opp_init_cpufreq_table() calls dev_pm_opp_get_opp_count(), which calls mutex_lock that can sleep. It indicates that atmtcp_v_send() can call functions which may sleep. Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL. This is found by a static analysis tool named DCNS written by myself. Signed-off-by: Jia-Ju Bai --- drivers/opp/cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/opp/cpu.c b/drivers/opp/cpu.c index 2d87bc1..0c09107 100644 --- a/drivers/opp/cpu.c +++ b/drivers/opp/cpu.c @@ -55,7 +55,7 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev, if (max_opps <= 0) return max_opps ? max_opps : -ENODATA; - freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC); + freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL); if (!freq_table) return -ENOMEM; -- 1.7.9.5