From 8b4865cd904650cbed7f2407e653934c621b8127 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Thu, 19 Sep 2024 10:11:21 +0200 Subject: [PATCH 1/2] cpufreq: intel_pstate: Make hwp_notify_lock a raw spinlock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit notify_hwp_interrupt() is called via sysvec_thermal() -> smp_thermal_vector() -> intel_thermal_interrupt() in hard irq context. For this reason it must not use a simple spin_lock that sleeps with PREEMPT_RT enabled. So convert it to a raw spinlock. Reported-by: xiao sheng wen Link: https://bugs.debian.org/1076483 Signed-off-by: Uwe Kleine-König Acked-by: Srinivas Pandruvada Acked-by: Sebastian Andrzej Siewior Tested-by: xiao sheng wen Link: https://patch.msgid.link/20240919081121.10784-2-ukleinek@debian.org Cc: All applicable Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index aaea9a39eced..b0018f371ea3 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1845,7 +1845,7 @@ static void intel_pstate_notify_work(struct work_struct *work) wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_STATUS, 0); } -static DEFINE_SPINLOCK(hwp_notify_lock); +static DEFINE_RAW_SPINLOCK(hwp_notify_lock); static cpumask_t hwp_intr_enable_mask; #define HWP_GUARANTEED_PERF_CHANGE_STATUS BIT(0) @@ -1868,7 +1868,7 @@ void notify_hwp_interrupt(void) if (!(value & status_mask)) return; - spin_lock_irqsave(&hwp_notify_lock, flags); + raw_spin_lock_irqsave(&hwp_notify_lock, flags); if (!cpumask_test_cpu(this_cpu, &hwp_intr_enable_mask)) goto ack_intr; @@ -1876,13 +1876,13 @@ void notify_hwp_interrupt(void) schedule_delayed_work(&all_cpu_data[this_cpu]->hwp_notify_work, msecs_to_jiffies(10)); - spin_unlock_irqrestore(&hwp_notify_lock, flags); + raw_spin_unlock_irqrestore(&hwp_notify_lock, flags); return; ack_intr: wrmsrl_safe(MSR_HWP_STATUS, 0); - spin_unlock_irqrestore(&hwp_notify_lock, flags); + raw_spin_unlock_irqrestore(&hwp_notify_lock, flags); } static void intel_pstate_disable_hwp_interrupt(struct cpudata *cpudata) @@ -1895,9 +1895,9 @@ static void intel_pstate_disable_hwp_interrupt(struct cpudata *cpudata) /* wrmsrl_on_cpu has to be outside spinlock as this can result in IPC */ wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00); - spin_lock_irq(&hwp_notify_lock); + raw_spin_lock_irq(&hwp_notify_lock); cancel_work = cpumask_test_and_clear_cpu(cpudata->cpu, &hwp_intr_enable_mask); - spin_unlock_irq(&hwp_notify_lock); + raw_spin_unlock_irq(&hwp_notify_lock); if (cancel_work) cancel_delayed_work_sync(&cpudata->hwp_notify_work); @@ -1912,10 +1912,10 @@ static void intel_pstate_enable_hwp_interrupt(struct cpudata *cpudata) if (boot_cpu_has(X86_FEATURE_HWP_NOTIFY)) { u64 interrupt_mask = HWP_GUARANTEED_PERF_CHANGE_REQ; - spin_lock_irq(&hwp_notify_lock); + raw_spin_lock_irq(&hwp_notify_lock); INIT_DELAYED_WORK(&cpudata->hwp_notify_work, intel_pstate_notify_work); cpumask_set_cpu(cpudata->cpu, &hwp_intr_enable_mask); - spin_unlock_irq(&hwp_notify_lock); + raw_spin_unlock_irq(&hwp_notify_lock); if (cpu_feature_enabled(X86_FEATURE_HWP_HIGHEST_PERF_CHANGE)) interrupt_mask |= HWP_HIGHEST_PERF_CHANGE_REQ; From c0f02536fffbbec71aced36d52a765f8c4493dc2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Miquel=20Sabat=C3=A9=20Sol=C3=A0?= Date: Tue, 17 Sep 2024 15:42:46 +0200 Subject: [PATCH 2/2] cpufreq: Avoid a bad reference count on CPU node MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In the parse_perf_domain function, if the call to of_parse_phandle_with_args returns an error, then the reference to the CPU device node that was acquired at the start of the function would not be properly decremented. Address this by declaring the variable with the __free(device_node) cleanup attribute. Signed-off-by: Miquel Sabaté Solà Acked-by: Viresh Kumar Link: https://patch.msgid.link/20240917134246.584026-1-mikisabate@gmail.com Cc: All applicable Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index e0e19d9c1323..7fe0981a7e46 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -1107,10 +1107,9 @@ static inline int parse_perf_domain(int cpu, const char *list_name, const char *cell_name, struct of_phandle_args *args) { - struct device_node *cpu_np; int ret; - cpu_np = of_cpu_device_node_get(cpu); + struct device_node *cpu_np __free(device_node) = of_cpu_device_node_get(cpu); if (!cpu_np) return -ENODEV; @@ -1118,9 +1117,6 @@ static inline int parse_perf_domain(int cpu, const char *list_name, args); if (ret < 0) return ret; - - of_node_put(cpu_np); - return 0; }