diff mbox series

opp: Prevent memory leak in dev_pm_opp_attach_genpd()

Message ID 1cadaccf3728ce84d5d0af50a48ce8caaa29eb53.1598853505.git.viresh.kumar@linaro.org
State Accepted
Commit cb60e9602cce1593eb1e9cdc8ee562815078a354
Headers show
Series opp: Prevent memory leak in dev_pm_opp_attach_genpd() | expand

Commit Message

Viresh Kumar Aug. 31, 2020, 5:58 a.m. UTC 
If dev_pm_opp_attach_genpd() is called multiple times (once for each CPU
sharing the table), then it would result in unwanted behavior like
memory leak, attaching the domain multiple times, etc.

Handle that by checking and returning earlier if the domains are already
attached. Now that dev_pm_opp_detach_genpd() can get called multiple
times as well, we need to protect that too.

Note that the virtual device pointers aren't returned in this case, as
they may become unavailable to some callers during the middle of the
operation.

Reported-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

---
 drivers/opp/core.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
2.25.0.rc1.19.g042ed3e048af
diff mbox series

Patch

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 000d0fcb4680..e65174725a4d 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1960,6 +1960,9 @@  static void _opp_detach_genpd(struct opp_table *opp_table)
 {
 	int index;
 
+	if (!opp_table->genpd_virt_devs)
+		return;
+
 	for (index = 0; index < opp_table->required_opp_count; index++) {
 		if (!opp_table->genpd_virt_devs[index])
 			continue;
@@ -2006,6 +2009,9 @@  struct opp_table *dev_pm_opp_attach_genpd(struct device *dev,
 	if (IS_ERR(opp_table))
 		return opp_table;
 
+	if (opp_table->genpd_virt_devs)
+		return opp_table;
+
 	/*
 	 * If the genpd's OPP table isn't already initialized, parsing of the
 	 * required-opps fail for dev. We should retry this after genpd's OPP