* H. Nikolaus Schaller [off-list ref] [180613 12:41]:

Now if I look into pinctrl_generic_add_group() and pinctrl_generic_get_group_name(),
pctldev->num_groups++ is not protected if pinctrl_generic_add_group() may be called by
two threads in parallel for the same pctldev. Hence a second thread may try to insert
a different node into the radix tree at the same selector index. This fails but there
is no error check - and the second entry is completely missing (but probably assumed to
be there).

Sounds like pinctrl-single.c is missing mutex around calls to
pinctrl_generic_add_group()?

Regards,

Tony