From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Kozlowski Subject: [PATCH 2/8] PM / domains: Protect reading loop over list of domains Date: Fri, 9 Jun 2017 18:08:47 +0200 Message-ID: <20170609160853.31789-3-krzk@kernel.org> References: <20170609160853.31789-1-krzk@kernel.org> Return-path: In-Reply-To: <20170609160853.31789-1-krzk@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: "Rafael J. Wysocki" , Kevin Hilman , Ulf Hansson , Pavel Machek , Len Brown , Greg Kroah-Hartman , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Krzysztof Kozlowski List-Id: linux-pm@vger.kernel.org The pm_genpd_present() iterates over list of domains so grabbing a gpd_list_lock mutex is necessary before calling it. Otherwise we could end up in iterating over and modifying the list at the same time. Signed-off-by: Krzysztof Kozlowski --- drivers/base/power/domain.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 2e8d0f423507..2a6935dc0164 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1099,8 +1099,13 @@ static void genpd_syscore_switch(struct device *dev, bool suspend) struct generic_pm_domain *genpd; genpd = dev_to_genpd(dev); - if (!pm_genpd_present(genpd)) + + mutex_lock(&gpd_list_lock); + if (!pm_genpd_present(genpd)) { + mutex_unlock(&gpd_list_lock); return; + } + mutex_unlock(&gpd_list_lock); if (suspend) { genpd->suspended_count++; -- 2.9.3