In the Linux kernel, the following vulnerability has been resolved: pmdomain: core: Fix detach procedure for virtual devices in genpd If a device is attached to a PM domain through genpd_dev_pm_attach_by_id(), genpd calls pm_runtime_enable() for the corresponding virtual device that it registers. While this avoids boilerplate code in drivers, there is no corresponding call to pm_runtime_disable() in genpd_dev_pm_detach(). This means these virtual devices are typically detached from its genpd, while runtime PM remains enabled for them, which is not how things are designed to work. In worst cases it may lead to critical errors, like a NULL pointer dereference bug in genpd_runtime_suspend(), which was recently reported. For another case, we may end up keeping an unnecessary vote for a performance state for the device. To fix these problems, let's add this missing call to pm_runtime_disable() in genpd_dev_pm_detach().
https://git.kernel.org/stable/c/8d44391a7f29e4601e8243f13498d0219bab2576
https://git.kernel.org/stable/c/707cb5df3eab32ddc52979418f7ace62941e6381
https://git.kernel.org/stable/c/51a7dd9cbae9210335ce398642ecaaa52c939eb5
https://git.kernel.org/stable/c/361518a26e4434e879db6ff43bf364795dcbfbff
https://git.kernel.org/stable/c/26735dfdd8930d9ef1fa92e590a9bf77726efdf6