[PATCH] PM / devfreq: mediatek: protect oop in critical session
DORMANTno replies
From: Mark Tseng <hidden>
Date: 2023-08-18 02:18:29
Also in:
linux-arm-kernel, linux-mediatek, linux-pm, lkml
Subsystem:
device frequency (devfreq), the rest · Maintainers:
MyungJoo Ham, Kyungmin Park, Chanwoo Choi, Linus Torvalds
mtk_ccifreq_opp_notifier is reenter function when policy0 / policy6 change freq, so metex_lock should protect all OPP event. Signed-off-by: Mark Tseng <redacted> --- drivers/devfreq/mtk-cci-devfreq.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/devfreq/mtk-cci-devfreq.c b/drivers/devfreq/mtk-cci-devfreq.c
index 83a73f0ccd80..b0ed25e33f2b 100644
--- a/drivers/devfreq/mtk-cci-devfreq.c
+++ b/drivers/devfreq/mtk-cci-devfreq.c@@ -137,6 +137,8 @@ static int mtk_ccifreq_target(struct device *dev, unsigned long *freq, if (drv->pre_freq == *freq) return 0; + mutex_lock(&drv->reg_lock); + inter_voltage = drv->inter_voltage; cci_pll = clk_get_parent(drv->cci_clk);
@@ -147,8 +149,6 @@ static int mtk_ccifreq_target(struct device *dev, unsigned long *freq, return PTR_ERR(opp); } - mutex_lock(&drv->reg_lock); - voltage = dev_pm_opp_get_voltage(opp); dev_pm_opp_put(opp);
@@ -227,9 +227,9 @@ static int mtk_ccifreq_opp_notifier(struct notifier_block *nb, drv = container_of(nb, struct mtk_ccifreq_drv, opp_nb); if (event == OPP_EVENT_ADJUST_VOLTAGE) { + mutex_lock(&drv->reg_lock); freq = dev_pm_opp_get_freq(opp); - mutex_lock(&drv->reg_lock); /* current opp item is changed */ if (freq == drv->pre_freq) { volt = dev_pm_opp_get_voltage(opp);
--
2.18.0