diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/arch_topology.c | 27 | ||||
| -rw-r--r-- | drivers/base/power/domain.c | 38 |
2 files changed, 38 insertions, 27 deletions
diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index c1179edc0f3b..921312a8d957 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -18,10 +18,11 @@ #include <linux/cpumask.h> #include <linux/init.h> #include <linux/percpu.h> +#include <linux/rcupdate.h> #include <linux/sched.h> #include <linux/smp.h> -static DEFINE_PER_CPU(struct scale_freq_data *, sft_data); +static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data); static struct cpumask scale_freq_counters_mask; static bool scale_freq_invariant; @@ -66,16 +67,20 @@ void topology_set_scale_freq_source(struct scale_freq_data *data, if (cpumask_empty(&scale_freq_counters_mask)) scale_freq_invariant = topology_scale_freq_invariant(); + rcu_read_lock(); + for_each_cpu(cpu, cpus) { - sfd = per_cpu(sft_data, cpu); + sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu)); /* Use ARCH provided counters whenever possible */ if (!sfd || sfd->source != SCALE_FREQ_SOURCE_ARCH) { - per_cpu(sft_data, cpu) = data; + rcu_assign_pointer(per_cpu(sft_data, cpu), data); cpumask_set_cpu(cpu, &scale_freq_counters_mask); } } + rcu_read_unlock(); + update_scale_freq_invariant(true); } EXPORT_SYMBOL_GPL(topology_set_scale_freq_source); @@ -86,22 +91,32 @@ void topology_clear_scale_freq_source(enum scale_freq_source source, struct scale_freq_data *sfd; int cpu; + rcu_read_lock(); + for_each_cpu(cpu, cpus) { - sfd = per_cpu(sft_data, cpu); + sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu)); if (sfd && sfd->source == source) { - per_cpu(sft_data, cpu) = NULL; + rcu_assign_pointer(per_cpu(sft_data, cpu), NULL); cpumask_clear_cpu(cpu, &scale_freq_counters_mask); } } + rcu_read_unlock(); + + /* + * Make sure all references to previous sft_data are dropped to avoid + * use-after-free races. + */ + synchronize_rcu(); + update_scale_freq_invariant(false); } EXPORT_SYMBOL_GPL(topology_clear_scale_freq_source); void topology_scale_freq_tick(void) { - struct scale_freq_data *sfd = *this_cpu_ptr(&sft_data); + struct scale_freq_data *sfd = rcu_dereference_sched(*this_cpu_ptr(&sft_data)); if (sfd) sfd->set_freq_scale(); diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index ab0b740cc0f1..a934c679e6ce 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -2018,8 +2018,8 @@ int pm_genpd_init(struct generic_pm_domain *genpd, mutex_lock(&gpd_list_lock); list_add(&genpd->gpd_list_node, &gpd_list); - genpd_debug_add(genpd); mutex_unlock(&gpd_list_lock); + genpd_debug_add(genpd); return 0; } @@ -2206,12 +2206,19 @@ static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate, static bool genpd_present(const struct generic_pm_domain *genpd) { + bool ret = false; const struct generic_pm_domain *gpd; - list_for_each_entry(gpd, &gpd_list, gpd_list_node) - if (gpd == genpd) - return true; - return false; + mutex_lock(&gpd_list_lock); + list_for_each_entry(gpd, &gpd_list, gpd_list_node) { + if (gpd == genpd) { + ret = true; + break; + } + } + mutex_unlock(&gpd_list_lock); + + return ret; } /** @@ -2222,15 +2229,13 @@ static bool genpd_present(const struct generic_pm_domain *genpd) int of_genpd_add_provider_simple(struct device_node *np, struct generic_pm_domain *genpd) { - int ret = -EINVAL; + int ret; if (!np || !genpd) return -EINVAL; - mutex_lock(&gpd_list_lock); - if (!genpd_present(genpd)) - goto unlock; + return -EINVAL; genpd->dev.of_node = np; @@ -2241,7 +2246,7 @@ int of_genpd_add_provider_simple(struct device_node *np, if (ret != -EPROBE_DEFER) dev_err(&genpd->dev, "Failed to add OPP table: %d\n", ret); - goto unlock; + return ret; } /* @@ -2259,16 +2264,13 @@ int of_genpd_add_provider_simple(struct device_node *np, dev_pm_opp_of_remove_table(&genpd->dev); } - goto unlock; + return ret; } genpd->provider = &np->fwnode; genpd->has_provider = true; -unlock: - mutex_unlock(&gpd_list_lock); - - return ret; + return 0; } EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple); @@ -2287,8 +2289,6 @@ int of_genpd_add_provider_onecell(struct device_node *np, if (!np || !data) return -EINVAL; - mutex_lock(&gpd_list_lock); - if (!data->xlate) data->xlate = genpd_xlate_onecell; @@ -2328,8 +2328,6 @@ int of_genpd_add_provider_onecell(struct device_node *np, if (ret < 0) goto error; - mutex_unlock(&gpd_list_lock); - return 0; error: @@ -2348,8 +2346,6 @@ error: } } - mutex_unlock(&gpd_list_lock); - return ret; } EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell); |