| Message ID | 1500626346-34316-1-git-send-email-wangkefeng.wang@huawei.com |
|---|---|
| State | New |
| Headers | show |
| Series | [hulk-4.1-next,1/2] cpuidle: Do not access cpuidle_devices when !CONFIG_CPU_IDLE | expand |
Sorry, please ignore this patch. On 2017/7/21 16:39, Kefeng Wang wrote: > From: Catalin Marinas <catalin.marinas@arm.com> > > mainline inclusion > from mainline-4.7 > commit 9bd616e3dbedfc103f158197c8ad93678849b1ed > category: bugfix > bugzilla: 3312 > DTS: NA > CVE: NA > > ------------------------------------------------- > > The cpuidle_devices per-CPU variable is only defined when CPU_IDLE is > enabled. Commit c8cc7d4de7a4 ("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> > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> > > Conflicts: > include/linux/cpuidle.h > --- > include/linux/cpuidle.h | 3 +++ > kernel/sched/idle.c | 2 +- > 2 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h > index 9c5e892..111ead2 100644 > --- a/include/linux/cpuidle.h > +++ b/include/linux/cpuidle.h > @@ -157,6 +157,8 @@ extern int cpuidle_enter_freeze(struct cpuidle_driver *drv, > struct cpuidle_device *dev); > > 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, > @@ -198,6 +200,7 @@ static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv, > {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 > > #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED > diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c > index fefcb1f..437d577e 100644 > --- a/kernel/sched/idle.c > +++ b/kernel/sched/idle.c > @@ -78,7 +78,7 @@ void __weak arch_cpu_idle(void) > */ > 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; > bool reflect;
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 9c5e892..111ead2 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -157,6 +157,8 @@ extern int cpuidle_enter_freeze(struct cpuidle_driver *drv, struct cpuidle_device *dev); 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, @@ -198,6 +200,7 @@ static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv, {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 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index fefcb1f..437d577e 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -78,7 +78,7 @@ void __weak arch_cpu_idle(void) */ 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; bool reflect;