summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorViresh Kumar <viresh.kumar@linaro.org>2019-10-18 14:11:58 +0530
committerViresh Kumar <viresh.kumar@linaro.org>2019-10-23 10:58:44 +0530
commitb19c23551be8de0d4e59fe6af70f10763e3cc595 (patch)
tree12a60bb2437dd98fcf9bca3f78e132ec4e0d0a7e /drivers
parent24957db1004353346583c9cc6d783db8f213e3ad (diff)
downloadlinux-b19c23551be8de0d4e59fe6af70f10763e3cc595.tar.bz2
opp: Reinitialize the list_kref before adding the static OPPs again
The list_kref reaches a count of 0 when all the static OPPs are removed, for example when dev_pm_opp_of_cpumask_remove_table() is called, though the actual OPP table may not get freed as it may still be referenced by other parts of the kernel, like from a call to dev_pm_opp_set_supported_hw(). And if we call dev_pm_opp_of_cpumask_add_table() again at this point, we must reinitialize the list_kref otherwise the kernel will hit a WARN() in kref infrastructure for incrementing a kref with value 0. Fixes: 11e1a1648298 ("opp: Don't decrement uninitialized list_kref") Reported-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/opp/of.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index 6dc41faf74b5..1cbb58240b80 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -663,6 +663,13 @@ static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
return 0;
}
+ /*
+ * Re-initialize list_kref every time we add static OPPs to the OPP
+ * table as the reference count may be 0 after the last tie static OPPs
+ * were removed.
+ */
+ kref_init(&opp_table->list_kref);
+
/* We have opp-table node now, iterate over it and add OPPs */
for_each_available_child_of_node(opp_table->np, np) {
opp = _opp_add_static_v2(opp_table, dev, np);