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b2a2ab039b
When dev_pm_opp_of_find_icc_paths() in _allocate_opp_table() returns
-EPROBE_DEFER, the opp_table is freed again, to wait until all the
interconnect paths are available.
However, if the OPP table is using required-opps then it may already
have been added to the global lazy_opp_tables list. The error path
does not remove the opp_table from the list again.
This can cause crashes later when the provider of the required-opps
is added, since we will iterate over OPP tables that have already been
freed. E.g.:
Unable to handle kernel NULL pointer dereference when read
CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.4.0-rc3
PC is at _of_add_opp_table_v2 (include/linux/of.h:949
drivers/opp/of.c:98 drivers/opp/of.c:344 drivers/opp/of.c:404
drivers/opp/of.c:1032) -> lazy_link_required_opp_table()
Fix this by calling _of_clear_opp_table() to remove the opp_table from
the list and clear other allocated resources. While at it, also add the
missing mutex_destroy() calls in the error path.
Cc: stable@vger.kernel.org
Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Fixes: 7eba0c7641 ("opp: Allow lazy-linking of required-opps")
Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.