1 files changed, 47 insertions, 20 deletions

diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
index 1e1a51510e83..71e2a9a89f6a 100644
--- a/drivers/firmware/arm_sdei.c
+++ b/drivers/firmware/arm_sdei.c
@@ -43,6 +43,8 @@ static asmlinkage void (*sdei_firmware_call)(unsigned long function_id,
 /* entry point from firmware to arch asm code */
 static unsigned long sdei_entry_point;
 
+static int sdei_hp_state;
+
 struct sdei_event {
 	/* These three are protected by the sdei_list_lock */
 	struct list_head	list;
@@ -301,8 +303,6 @@ int sdei_mask_local_cpu(void)
 {
 	int err;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL);
 	if (err && err != -EIO) {
 		pr_warn_once("failed to mask CPU[%u]: %d\n",
@@ -315,6 +315,7 @@ int sdei_mask_local_cpu(void)
 
 static void _ipi_mask_cpu(void *ignored)
 {
+	WARN_ON_ONCE(preemptible());
 	sdei_mask_local_cpu();
 }
 
@@ -322,8 +323,6 @@ int sdei_unmask_local_cpu(void)
 {
 	int err;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL);
 	if (err && err != -EIO) {
 		pr_warn_once("failed to unmask CPU[%u]: %d\n",
@@ -336,6 +335,7 @@ int sdei_unmask_local_cpu(void)
 
 static void _ipi_unmask_cpu(void *ignored)
 {
+	WARN_ON_ONCE(preemptible());
 	sdei_unmask_local_cpu();
 }
 
@@ -343,6 +343,8 @@ static void _ipi_private_reset(void *ignored)
 {
 	int err;
 
+	WARN_ON_ONCE(preemptible());
+
 	err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0,
 			     NULL);
 	if (err && err != -EIO)
@@ -389,8 +391,6 @@ static void _local_event_enable(void *data)
 	int err;
 	struct sdei_crosscall_args *arg = data;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = sdei_api_event_enable(arg->event->event_num);
 
 	sdei_cross_call_return(arg, err);
@@ -479,8 +479,6 @@ static void _local_event_unregister(void *data)
 	int err;
 	struct sdei_crosscall_args *arg = data;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = sdei_api_event_unregister(arg->event->event_num);
 
 	sdei_cross_call_return(arg, err);
@@ -561,8 +559,6 @@ static void _local_event_register(void *data)
 	struct sdei_registered_event *reg;
 	struct sdei_crosscall_args *arg = data;
 
-	WARN_ON(preemptible());
-
 	reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id());
 	err = sdei_api_event_register(arg->event->event_num, sdei_entry_point,
 				      reg, 0, 0);
@@ -717,6 +713,8 @@ static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action,
 {
 	int rv;
 
+	WARN_ON_ONCE(preemptible());
+
 	switch (action) {
 	case CPU_PM_ENTER:
 		rv = sdei_mask_local_cpu();
@@ -765,7 +763,7 @@ static int sdei_device_freeze(struct device *dev)
 	int err;
 
 	/* unregister private events */
-	cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
+	cpuhp_remove_state(sdei_hp_state);
 
 	err = sdei_unregister_shared();
 	if (err)
@@ -786,12 +784,15 @@ static int sdei_device_thaw(struct device *dev)
 		return err;
 	}
 
-	err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
+	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SDEI",
 				&sdei_cpuhp_up, &sdei_cpuhp_down);
-	if (err)
+	if (err < 0) {
 		pr_warn("Failed to re-register CPU hotplug notifier...\n");
+		return err;
+	}
 
-	return err;
+	sdei_hp_state = err;
+	return 0;
 }
 
 static int sdei_device_restore(struct device *dev)
@@ -823,7 +824,7 @@ static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action,
 	 * We are going to reset the interface, after this there is no point
 	 * doing work when we take CPUs offline.
 	 */
-	cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
+	cpuhp_remove_state(sdei_hp_state);
 
 	sdei_platform_reset();
 
@@ -1003,13 +1004,15 @@ static int sdei_probe(struct platform_device *pdev)
 		goto remove_cpupm;
 	}
 
-	err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
+	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SDEI",
 				&sdei_cpuhp_up, &sdei_cpuhp_down);
-	if (err) {
+	if (err < 0) {
 		pr_warn("Failed to register CPU hotplug notifier...\n");
 		goto remove_reboot;
 	}
 
+	sdei_hp_state = err;
+
 	return 0;
 
 remove_reboot:
@@ -1059,13 +1062,12 @@ static bool __init sdei_present_acpi(void)
 	return true;
 }
 
-void __init sdei_init(void)
+void __init acpi_sdei_init(void)
 {
 	struct platform_device *pdev;
 	int ret;
 
-	ret = platform_driver_register(&sdei_driver);
-	if (ret || !sdei_present_acpi())
+	if (!sdei_present_acpi())
 		return;
 
 	pdev = platform_device_register_simple(sdei_driver.driver.name,
@@ -1078,6 +1080,12 @@ void __init sdei_init(void)
 	}
 }
 
+static int __init sdei_init(void)
+{
+	return platform_driver_register(&sdei_driver);
+}
+arch_initcall(sdei_init);
+
 int sdei_event_handler(struct pt_regs *regs,
 		       struct sdei_registered_event *arg)
 {
@@ -1092,3 +1100,22 @@ int sdei_event_handler(struct pt_regs *regs,
 	return err;
 }
 NOKPROBE_SYMBOL(sdei_event_handler);
+
+void sdei_handler_abort(void)
+{
+	/*
+	 * If the crash happened in an SDEI event handler then we need to
+	 * finish the handler with the firmware so that we can have working
+	 * interrupts in the crash kernel.
+	 */
+	if (__this_cpu_read(sdei_active_critical_event)) {
+	        pr_warn("still in SDEI critical event context, attempting to finish handler.\n");
+	        __sdei_handler_abort();
+	        __this_cpu_write(sdei_active_critical_event, NULL);
+	}
+	if (__this_cpu_read(sdei_active_normal_event)) {
+	        pr_warn("still in SDEI normal event context, attempting to finish handler.\n");
+	        __sdei_handler_abort();
+	        __this_cpu_write(sdei_active_normal_event, NULL);
+	}
+}