cpuidle: Do not access cpuidle_devices when !CONFIG_CPU_IDLE (9bd616e3) · Commits · 戴 / test

The cpuidle_devices per-CPU variable is only defined when CPU_IDLE is enabled. Commit ("sched/idle: Reorganize the idle loop") removed the #ifdef CONFIG_CPU_IDLE around cpuidle_idle_call() with the compiler optimising away __this_cpu_read(cpuidle_devices). However, with CONFIG_UBSAN && !CONFIG_CPU_IDLE, this optimisation no longer happens and the kernel fails to link since cpuidle_devices is not defined. This patch introduces an accessor function for the current CPU cpuidle device (returning NULL when !CONFIG_CPU_IDLE) and uses it in cpuidle_idle_call(). Signed-off-by:

Catalin Marinas <catalin.marinas@arm.com> Cc: 4.5+ <stable@vger.kernel.org> # 4.5+ Signed-off-by:

Rafael J. Wysocki <rafael.j.wysocki@intel.com>

include/linux/cpuidle.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -152,6 +152,8 @@ extern void cpuidle_disable_device(struct cpuidle_device *dev);
		extern int cpuidle_play_dead(void);

		extern struct cpuidle_driver cpuidle_get_cpu_driver(struct cpuidle_device dev);
		static inline struct cpuidle_device *cpuidle_get_device(void)
		{return __this_cpu_read(cpuidle_devices); }
		#else
		static inline void disable_cpuidle(void) { }
		static inline bool cpuidle_not_available(struct cpuidle_driver *drv,
		@@ -187,6 +189,7 @@ static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
		static inline int cpuidle_play_dead(void) {return -ENODEV; }
		static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
		struct cpuidle_device *dev) {return NULL; }
		static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; }
		#endif

		#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND)

kernel/sched/idle.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -127,7 +127,7 @@ static int call_cpuidle(struct cpuidle_driver drv, struct cpuidle_device dev,
		*/
		static void cpuidle_idle_call(void)
		{
		struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
		struct cpuidle_device *dev = cpuidle_get_device();
		struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
		int next_state, entered_state;

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