mirror of https://gitee.com/openkylin/linux.git
ab47bd964a
The work cancellation code, the thermal zone unregistering, the work code and the interrupt notification function are racy against each other and against cpu hotplug and module exit. The random locking sprinkeled all over the place does not help anything and probably exists to make people feel good. The resulting issues (mainly use after free) are probably hard to trigger, but they clearly exist Protect the package list with a spinlock so it can be accessed from the interrupt notifier and also from the work function. The add/removal code in the hotplug callbacks take the lock for list manipulation. That makes sure that on removal neither the interrupt notifier nor the work function can access the about to be freed package structure anymore. The thermal zone unregistering is another trainwreck. It's not serialized against the work function. So unregistering the zone device can race with the work function and cause havoc. Protect the thermal zone with a mutex, which is held in the work function to make sure that the zone device is not being unregistered concurrently. To solve the module exit issues, we simply invoke the cpu offline callback and let it work its magic. For that it's required to keep track of the participating cpus in a package, because topology_core_mask is not affected by calling the offline callback for teardown of the driver, so it would never free the package as there is always a valid target in topology_core_mask. Use proper names for the locks so it's clear what they are for and add a pile of comments to explain the protection rules. It's amazing that fixing the locking and adding 30 lines of comments explaining it still removes more lines than it adds. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> |
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| .. | ||
| int340x_thermal | ||
| qcom | ||
| samsung | ||
| st | ||
| tegra | ||
| ti-soc-thermal | ||
| Kconfig | ||
| Makefile | ||
| armada_thermal.c | ||
| clock_cooling.c | ||
| cpu_cooling.c | ||
| db8500_cpufreq_cooling.c | ||
| db8500_thermal.c | ||
| devfreq_cooling.c | ||
| dove_thermal.c | ||
| fair_share.c | ||
| gov_bang_bang.c | ||
| hisi_thermal.c | ||
| imx_thermal.c | ||
| intel_bxt_pmic_thermal.c | ||
| intel_pch_thermal.c | ||
| intel_powerclamp.c | ||
| intel_quark_dts_thermal.c | ||
| intel_soc_dts_iosf.c | ||
| intel_soc_dts_iosf.h | ||
| intel_soc_dts_thermal.c | ||
| kirkwood_thermal.c | ||
| max77620_thermal.c | ||
| mtk_thermal.c | ||
| of-thermal.c | ||
| power_allocator.c | ||
| qcom-spmi-temp-alarm.c | ||
| qoriq_thermal.c | ||
| rcar_thermal.c | ||
| rockchip_thermal.c | ||
| spear_thermal.c | ||
| step_wise.c | ||
| tango_thermal.c | ||
| thermal-generic-adc.c | ||
| thermal_core.c | ||
| thermal_core.h | ||
| thermal_hwmon.c | ||
| thermal_hwmon.h | ||
| user_space.c | ||
| x86_pkg_temp_thermal.c | ||