lkml.org 
[lkml]   [2023]   [Aug]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] PM / devfreq: mediatek: protect oop in critical session
Date
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 <chun-jen.tseng@mediatek.com>
---
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
\
 
 \ /
  Last update: 2023-08-18 04:19    [W:0.052 / U:1.364 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site