From b10abd0a8859493a93c6b8020f2be2587557749d Mon Sep 17 00:00:00 2001 From: "Joel Fernandes (Google)" Date: Wed, 20 Mar 2019 20:34:23 -0400 Subject: sched/cpufreq: Annotate cpufreq_update_util_data pointer with __rcu Recently I added an RCU annotation check to rcu_assign_pointer(). All pointers assigned to RCU protected data are to be annotated with __rcu inorder to be able to use rcu_assign_pointer() similar to checks in other RCU APIs. This resulted in a sparse error: kernel//sched/cpufreq.c:41:9: sparse: error: incompatible types in comparison expression (different address spaces) Fix this by annotating cpufreq_update_util_data pointer with __rcu. This will also help sparse catch any future RCU misuage bugs. Signed-off-by: Joel Fernandes (Google) [ From an RCU perspective. ] Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Paul E. McKenney Cc: Josh Triplett Cc: Lai Jiangshan Cc: Linus Torvalds Cc: Luc Van Oostenryck Cc: Mathieu Desnoyers Cc: Mike Galbraith Cc: Morten Rasmussen Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Cc: keescook@chromium.org Cc: kernel-hardening@lists.openwall.com Cc: kernel-team@android.com Link: https://lkml.kernel.org/r/20190321003426.160260-2-joel@joelfernandes.org Signed-off-by: Ingo Molnar --- kernel/sched/cpufreq.c | 2 +- kernel/sched/sched.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/sched') diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c index 835671f0f917..b5dcd1d83c7f 100644 --- a/kernel/sched/cpufreq.c +++ b/kernel/sched/cpufreq.c @@ -7,7 +7,7 @@ */ #include "sched.h" -DEFINE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); +DEFINE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); /** * cpufreq_add_update_util_hook - Populate the CPU's update_util_data pointer. diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index efa686eeff26..713715dd00cf 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2185,7 +2185,7 @@ static inline u64 irq_time_read(int cpu) #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ #ifdef CONFIG_CPU_FREQ -DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); +DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); /** * cpufreq_update_util - Take a note about CPU utilization changes. -- cgit v1.2.3