1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2017 Arm Ltd.
3 #define pr_fmt(fmt) "sdei: " fmt
5 #include <linux/acpi.h>
6 #include <linux/arm_sdei.h>
7 #include <linux/arm-smccc.h>
8 #include <linux/atomic.h>
9 #include <linux/bitops.h>
10 #include <linux/compiler.h>
11 #include <linux/cpuhotplug.h>
12 #include <linux/cpu.h>
13 #include <linux/cpu_pm.h>
14 #include <linux/errno.h>
15 #include <linux/hardirq.h>
16 #include <linux/kernel.h>
17 #include <linux/kprobes.h>
18 #include <linux/kvm_host.h>
19 #include <linux/list.h>
20 #include <linux/mutex.h>
21 #include <linux/notifier.h>
23 #include <linux/of_platform.h>
24 #include <linux/percpu.h>
25 #include <linux/platform_device.h>
27 #include <linux/ptrace.h>
28 #include <linux/preempt.h>
29 #include <linux/reboot.h>
30 #include <linux/slab.h>
31 #include <linux/smp.h>
32 #include <linux/spinlock.h>
33 #include <linux/uaccess.h>
36 * The call to use to reach the firmware.
38 static asmlinkage void (*sdei_firmware_call)(unsigned long function_id,
39 unsigned long arg0, unsigned long arg1,
40 unsigned long arg2, unsigned long arg3,
41 unsigned long arg4, struct arm_smccc_res *res);
43 /* entry point from firmware to arch asm code */
44 static unsigned long sdei_entry_point;
46 static int sdei_hp_state;
49 /* These three are protected by the sdei_list_lock */
50 struct list_head list;
58 /* This pointer is handed to firmware as the event argument. */
61 struct sdei_registered_event *registered;
63 /* CPU private events */
64 struct sdei_registered_event __percpu *private_registered;
68 /* Take the mutex for any API call or modification. Take the mutex first. */
69 static DEFINE_MUTEX(sdei_events_lock);
71 /* and then hold this when modifying the list */
72 static DEFINE_SPINLOCK(sdei_list_lock);
73 static LIST_HEAD(sdei_list);
75 /* Private events are registered/enabled via IPI passing one of these */
76 struct sdei_crosscall_args {
77 struct sdei_event *event;
82 #define CROSSCALL_INIT(arg, event) (arg.event = event, \
83 arg.first_error = 0, \
84 atomic_set(&arg.errors, 0))
86 static inline int sdei_do_cross_call(void *fn, struct sdei_event * event)
88 struct sdei_crosscall_args arg;
90 CROSSCALL_INIT(arg, event);
91 on_each_cpu(fn, &arg, true);
93 return arg.first_error;
97 sdei_cross_call_return(struct sdei_crosscall_args *arg, int err)
99 if (err && (atomic_inc_return(&arg->errors) == 1))
100 arg->first_error = err;
103 static int sdei_to_linux_errno(unsigned long sdei_err)
106 case SDEI_NOT_SUPPORTED:
108 case SDEI_INVALID_PARAMETERS:
114 case SDEI_OUT_OF_RESOURCE:
118 /* Not an error value ... */
123 * If x0 is any of these values, then the call failed, use sdei_to_linux_errno()
126 static int sdei_is_err(struct arm_smccc_res *res)
129 case SDEI_NOT_SUPPORTED:
130 case SDEI_INVALID_PARAMETERS:
133 case SDEI_OUT_OF_RESOURCE:
140 static int invoke_sdei_fn(unsigned long function_id, unsigned long arg0,
141 unsigned long arg1, unsigned long arg2,
142 unsigned long arg3, unsigned long arg4,
146 struct arm_smccc_res res;
148 if (sdei_firmware_call) {
149 sdei_firmware_call(function_id, arg0, arg1, arg2, arg3, arg4,
151 if (sdei_is_err(&res))
152 err = sdei_to_linux_errno(res.a0);
155 * !sdei_firmware_call means we failed to probe or called
156 * sdei_mark_interface_broken(). -EIO is not an error returned
157 * by sdei_to_linux_errno() and is used to suppress messages
161 res.a0 = SDEI_NOT_SUPPORTED;
170 static struct sdei_event *sdei_event_find(u32 event_num)
172 struct sdei_event *e, *found = NULL;
174 lockdep_assert_held(&sdei_events_lock);
176 spin_lock(&sdei_list_lock);
177 list_for_each_entry(e, &sdei_list, list) {
178 if (e->event_num == event_num) {
183 spin_unlock(&sdei_list_lock);
188 int sdei_api_event_context(u32 query, u64 *result)
190 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_CONTEXT, query, 0, 0, 0, 0,
193 NOKPROBE_SYMBOL(sdei_api_event_context);
195 static int sdei_api_event_get_info(u32 event, u32 info, u64 *result)
197 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_GET_INFO, event, info, 0,
201 static struct sdei_event *sdei_event_create(u32 event_num,
202 sdei_event_callback *cb,
207 struct sdei_event *event;
208 struct sdei_registered_event *reg;
210 lockdep_assert_held(&sdei_events_lock);
212 event = kzalloc(sizeof(*event), GFP_KERNEL);
214 return ERR_PTR(-ENOMEM);
216 INIT_LIST_HEAD(&event->list);
217 event->event_num = event_num;
219 err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY,
225 event->priority = result;
227 err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_TYPE,
233 event->type = result;
235 if (event->type == SDEI_EVENT_TYPE_SHARED) {
236 reg = kzalloc(sizeof(*reg), GFP_KERNEL);
239 return ERR_PTR(-ENOMEM);
242 reg->event_num = event_num;
243 reg->priority = event->priority;
246 reg->callback_arg = cb_arg;
247 event->registered = reg;
250 struct sdei_registered_event __percpu *regs;
252 regs = alloc_percpu(struct sdei_registered_event);
255 return ERR_PTR(-ENOMEM);
258 for_each_possible_cpu(cpu) {
259 reg = per_cpu_ptr(regs, cpu);
261 reg->event_num = event->event_num;
262 reg->priority = event->priority;
264 reg->callback_arg = cb_arg;
267 event->private_registered = regs;
270 if (sdei_event_find(event_num)) {
271 kfree(event->registered);
273 event = ERR_PTR(-EBUSY);
275 spin_lock(&sdei_list_lock);
276 list_add(&event->list, &sdei_list);
277 spin_unlock(&sdei_list_lock);
283 static void sdei_event_destroy(struct sdei_event *event)
285 lockdep_assert_held(&sdei_events_lock);
287 spin_lock(&sdei_list_lock);
288 list_del(&event->list);
289 spin_unlock(&sdei_list_lock);
291 if (event->type == SDEI_EVENT_TYPE_SHARED)
292 kfree(event->registered);
294 free_percpu(event->private_registered);
299 static int sdei_api_get_version(u64 *version)
301 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_VERSION, 0, 0, 0, 0, 0, version);
304 int sdei_mask_local_cpu(void)
308 err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL);
309 if (err && err != -EIO) {
310 pr_warn_once("failed to mask CPU[%u]: %d\n",
311 smp_processor_id(), err);
318 static void _ipi_mask_cpu(void *ignored)
320 WARN_ON_ONCE(preemptible());
321 sdei_mask_local_cpu();
324 int sdei_unmask_local_cpu(void)
328 err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL);
329 if (err && err != -EIO) {
330 pr_warn_once("failed to unmask CPU[%u]: %d\n",
331 smp_processor_id(), err);
338 static void _ipi_unmask_cpu(void *ignored)
340 WARN_ON_ONCE(preemptible());
341 sdei_unmask_local_cpu();
344 static void _ipi_private_reset(void *ignored)
348 WARN_ON_ONCE(preemptible());
350 err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0,
352 if (err && err != -EIO)
353 pr_warn_once("failed to reset CPU[%u]: %d\n",
354 smp_processor_id(), err);
357 static int sdei_api_shared_reset(void)
359 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_SHARED_RESET, 0, 0, 0, 0, 0,
363 static void sdei_mark_interface_broken(void)
365 pr_err("disabling SDEI firmware interface\n");
366 on_each_cpu(&_ipi_mask_cpu, NULL, true);
367 sdei_firmware_call = NULL;
370 static int sdei_platform_reset(void)
374 on_each_cpu(&_ipi_private_reset, NULL, true);
375 err = sdei_api_shared_reset();
377 pr_err("Failed to reset platform: %d\n", err);
378 sdei_mark_interface_broken();
384 static int sdei_api_event_enable(u32 event_num)
386 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_ENABLE, event_num, 0, 0, 0,
390 /* Called directly by the hotplug callbacks */
391 static void _local_event_enable(void *data)
394 struct sdei_crosscall_args *arg = data;
396 err = sdei_api_event_enable(arg->event->event_num);
398 sdei_cross_call_return(arg, err);
401 int sdei_event_enable(u32 event_num)
404 struct sdei_event *event;
406 mutex_lock(&sdei_events_lock);
407 event = sdei_event_find(event_num);
409 mutex_unlock(&sdei_events_lock);
415 if (event->type == SDEI_EVENT_TYPE_SHARED)
416 err = sdei_api_event_enable(event->event_num);
418 err = sdei_do_cross_call(_local_event_enable, event);
421 spin_lock(&sdei_list_lock);
422 event->reenable = true;
423 spin_unlock(&sdei_list_lock);
426 mutex_unlock(&sdei_events_lock);
430 EXPORT_SYMBOL(sdei_event_enable);
432 static int sdei_api_event_disable(u32 event_num)
434 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_DISABLE, event_num, 0, 0,
438 static void _ipi_event_disable(void *data)
441 struct sdei_crosscall_args *arg = data;
443 err = sdei_api_event_disable(arg->event->event_num);
445 sdei_cross_call_return(arg, err);
448 int sdei_event_disable(u32 event_num)
451 struct sdei_event *event;
453 mutex_lock(&sdei_events_lock);
454 event = sdei_event_find(event_num);
456 mutex_unlock(&sdei_events_lock);
460 spin_lock(&sdei_list_lock);
461 event->reenable = false;
462 spin_unlock(&sdei_list_lock);
464 if (event->type == SDEI_EVENT_TYPE_SHARED)
465 err = sdei_api_event_disable(event->event_num);
467 err = sdei_do_cross_call(_ipi_event_disable, event);
468 mutex_unlock(&sdei_events_lock);
472 EXPORT_SYMBOL(sdei_event_disable);
474 static int sdei_api_event_unregister(u32 event_num)
476 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_UNREGISTER, event_num, 0,
480 /* Called directly by the hotplug callbacks */
481 static void _local_event_unregister(void *data)
484 struct sdei_crosscall_args *arg = data;
486 err = sdei_api_event_unregister(arg->event->event_num);
488 sdei_cross_call_return(arg, err);
491 static int _sdei_event_unregister(struct sdei_event *event)
493 lockdep_assert_held(&sdei_events_lock);
495 if (event->type == SDEI_EVENT_TYPE_SHARED)
496 return sdei_api_event_unregister(event->event_num);
498 return sdei_do_cross_call(_local_event_unregister, event);
501 int sdei_event_unregister(u32 event_num)
504 struct sdei_event *event;
508 mutex_lock(&sdei_events_lock);
509 event = sdei_event_find(event_num);
512 pr_warn("Event %u not registered\n", event_num);
517 spin_lock(&sdei_list_lock);
518 event->reregister = false;
519 event->reenable = false;
520 spin_unlock(&sdei_list_lock);
522 err = _sdei_event_unregister(event);
526 sdei_event_destroy(event);
528 mutex_unlock(&sdei_events_lock);
532 EXPORT_SYMBOL(sdei_event_unregister);
535 * unregister events, but don't destroy them as they are re-registered by
536 * sdei_reregister_shared().
538 static int sdei_unregister_shared(void)
541 struct sdei_event *event;
543 mutex_lock(&sdei_events_lock);
544 spin_lock(&sdei_list_lock);
545 list_for_each_entry(event, &sdei_list, list) {
546 if (event->type != SDEI_EVENT_TYPE_SHARED)
549 err = _sdei_event_unregister(event);
553 spin_unlock(&sdei_list_lock);
554 mutex_unlock(&sdei_events_lock);
559 static int sdei_api_event_register(u32 event_num, unsigned long entry_point,
560 void *arg, u64 flags, u64 affinity)
562 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_REGISTER, event_num,
563 (unsigned long)entry_point, (unsigned long)arg,
564 flags, affinity, NULL);
567 /* Called directly by the hotplug callbacks */
568 static void _local_event_register(void *data)
571 struct sdei_registered_event *reg;
572 struct sdei_crosscall_args *arg = data;
574 reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id());
575 err = sdei_api_event_register(arg->event->event_num, sdei_entry_point,
578 sdei_cross_call_return(arg, err);
581 static int _sdei_event_register(struct sdei_event *event)
585 lockdep_assert_held(&sdei_events_lock);
587 if (event->type == SDEI_EVENT_TYPE_SHARED)
588 return sdei_api_event_register(event->event_num,
591 SDEI_EVENT_REGISTER_RM_ANY, 0);
593 err = sdei_do_cross_call(_local_event_register, event);
595 sdei_do_cross_call(_local_event_unregister, event);
600 int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg)
603 struct sdei_event *event;
607 mutex_lock(&sdei_events_lock);
609 if (sdei_event_find(event_num)) {
610 pr_warn("Event %u already registered\n", event_num);
615 event = sdei_event_create(event_num, cb, arg);
617 err = PTR_ERR(event);
618 pr_warn("Failed to create event %u: %d\n", event_num,
624 err = _sdei_event_register(event);
626 sdei_event_destroy(event);
627 pr_warn("Failed to register event %u: %d\n", event_num,
630 spin_lock(&sdei_list_lock);
631 event->reregister = true;
632 spin_unlock(&sdei_list_lock);
636 mutex_unlock(&sdei_events_lock);
640 EXPORT_SYMBOL(sdei_event_register);
642 static int sdei_reregister_event(struct sdei_event *event)
646 lockdep_assert_held(&sdei_events_lock);
648 err = _sdei_event_register(event);
650 pr_err("Failed to re-register event %u\n", event->event_num);
651 sdei_event_destroy(event);
655 if (event->reenable) {
656 if (event->type == SDEI_EVENT_TYPE_SHARED)
657 err = sdei_api_event_enable(event->event_num);
659 err = sdei_do_cross_call(_local_event_enable, event);
663 pr_err("Failed to re-enable event %u\n", event->event_num);
668 static int sdei_reregister_shared(void)
671 struct sdei_event *event;
673 mutex_lock(&sdei_events_lock);
674 spin_lock(&sdei_list_lock);
675 list_for_each_entry(event, &sdei_list, list) {
676 if (event->type != SDEI_EVENT_TYPE_SHARED)
679 if (event->reregister) {
680 err = sdei_reregister_event(event);
685 spin_unlock(&sdei_list_lock);
686 mutex_unlock(&sdei_events_lock);
691 static int sdei_cpuhp_down(unsigned int cpu)
693 struct sdei_event *event;
694 struct sdei_crosscall_args arg;
696 /* un-register private events */
697 spin_lock(&sdei_list_lock);
698 list_for_each_entry(event, &sdei_list, list) {
699 if (event->type == SDEI_EVENT_TYPE_SHARED)
702 CROSSCALL_INIT(arg, event);
703 /* call the cross-call function locally... */
704 _local_event_unregister(&arg);
706 pr_err("Failed to unregister event %u: %d\n",
707 event->event_num, arg.first_error);
709 spin_unlock(&sdei_list_lock);
711 return sdei_mask_local_cpu();
714 static int sdei_cpuhp_up(unsigned int cpu)
716 struct sdei_event *event;
717 struct sdei_crosscall_args arg;
719 /* re-register/enable private events */
720 spin_lock(&sdei_list_lock);
721 list_for_each_entry(event, &sdei_list, list) {
722 if (event->type == SDEI_EVENT_TYPE_SHARED)
725 if (event->reregister) {
726 CROSSCALL_INIT(arg, event);
727 /* call the cross-call function locally... */
728 _local_event_register(&arg);
730 pr_err("Failed to re-register event %u: %d\n",
731 event->event_num, arg.first_error);
734 if (event->reenable) {
735 CROSSCALL_INIT(arg, event);
736 _local_event_enable(&arg);
738 pr_err("Failed to re-enable event %u: %d\n",
739 event->event_num, arg.first_error);
742 spin_unlock(&sdei_list_lock);
744 return sdei_unmask_local_cpu();
747 /* When entering idle, mask/unmask events for this cpu */
748 static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action,
753 WARN_ON_ONCE(preemptible());
757 rv = sdei_mask_local_cpu();
760 case CPU_PM_ENTER_FAILED:
761 rv = sdei_unmask_local_cpu();
768 return notifier_from_errno(rv);
773 static struct notifier_block sdei_pm_nb = {
774 .notifier_call = sdei_pm_notifier,
777 static int sdei_device_suspend(struct device *dev)
779 on_each_cpu(_ipi_mask_cpu, NULL, true);
784 static int sdei_device_resume(struct device *dev)
786 on_each_cpu(_ipi_unmask_cpu, NULL, true);
792 * We need all events to be reregistered when we resume from hibernate.
794 * The sequence is freeze->thaw. Reboot. freeze->restore. We unregister
795 * events during freeze, then re-register and re-enable them during thaw
798 static int sdei_device_freeze(struct device *dev)
802 /* unregister private events */
803 cpuhp_remove_state(sdei_entry_point);
805 err = sdei_unregister_shared();
812 static int sdei_device_thaw(struct device *dev)
816 /* re-register shared events */
817 err = sdei_reregister_shared();
819 pr_warn("Failed to re-register shared events...\n");
820 sdei_mark_interface_broken();
824 err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SDEI",
825 &sdei_cpuhp_up, &sdei_cpuhp_down);
827 pr_warn("Failed to re-register CPU hotplug notifier...\n");
835 static int sdei_device_restore(struct device *dev)
839 err = sdei_platform_reset();
843 return sdei_device_thaw(dev);
846 static const struct dev_pm_ops sdei_pm_ops = {
847 .suspend = sdei_device_suspend,
848 .resume = sdei_device_resume,
849 .freeze = sdei_device_freeze,
850 .thaw = sdei_device_thaw,
851 .restore = sdei_device_restore,
855 * Mask all CPUs and unregister all events on panic, reboot or kexec.
857 static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action,
861 * We are going to reset the interface, after this there is no point
862 * doing work when we take CPUs offline.
864 cpuhp_remove_state(sdei_hp_state);
866 sdei_platform_reset();
871 static struct notifier_block sdei_reboot_nb = {
872 .notifier_call = sdei_reboot_notifier,
875 static void sdei_smccc_smc(unsigned long function_id,
876 unsigned long arg0, unsigned long arg1,
877 unsigned long arg2, unsigned long arg3,
878 unsigned long arg4, struct arm_smccc_res *res)
880 arm_smccc_smc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res);
883 static void sdei_smccc_hvc(unsigned long function_id,
884 unsigned long arg0, unsigned long arg1,
885 unsigned long arg2, unsigned long arg3,
886 unsigned long arg4, struct arm_smccc_res *res)
888 arm_smccc_hvc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res);
891 static int sdei_get_conduit(struct platform_device *pdev)
894 struct device_node *np = pdev->dev.of_node;
896 sdei_firmware_call = NULL;
898 if (of_property_read_string(np, "method", &method)) {
899 pr_warn("missing \"method\" property\n");
900 return CONDUIT_INVALID;
903 if (!strcmp("hvc", method)) {
904 sdei_firmware_call = &sdei_smccc_hvc;
906 } else if (!strcmp("smc", method)) {
907 sdei_firmware_call = &sdei_smccc_smc;
911 pr_warn("invalid \"method\" property: %s\n", method);
912 } else if (IS_ENABLED(CONFIG_ACPI) && !acpi_disabled) {
913 if (acpi_psci_use_hvc()) {
914 sdei_firmware_call = &sdei_smccc_hvc;
917 sdei_firmware_call = &sdei_smccc_smc;
922 return CONDUIT_INVALID;
925 static int sdei_probe(struct platform_device *pdev)
931 conduit = sdei_get_conduit(pdev);
932 if (!sdei_firmware_call)
935 err = sdei_api_get_version(&ver);
936 if (err == -EOPNOTSUPP)
937 pr_err("advertised but not implemented in platform firmware\n");
939 pr_err("Failed to get SDEI version: %d\n", err);
940 sdei_mark_interface_broken();
944 pr_info("SDEIv%d.%d (0x%x) detected in firmware.\n",
945 (int)SDEI_VERSION_MAJOR(ver), (int)SDEI_VERSION_MINOR(ver),
946 (int)SDEI_VERSION_VENDOR(ver));
948 if (SDEI_VERSION_MAJOR(ver) != 1) {
949 pr_warn("Conflicting SDEI version detected.\n");
950 sdei_mark_interface_broken();
954 err = sdei_platform_reset();
958 sdei_entry_point = sdei_arch_get_entry_point(conduit);
959 if (!sdei_entry_point) {
960 /* Not supported due to hardware or boot configuration */
961 sdei_mark_interface_broken();
965 err = cpu_pm_register_notifier(&sdei_pm_nb);
967 pr_warn("Failed to register CPU PM notifier...\n");
971 err = register_reboot_notifier(&sdei_reboot_nb);
973 pr_warn("Failed to register reboot notifier...\n");
977 err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SDEI",
978 &sdei_cpuhp_up, &sdei_cpuhp_down);
980 pr_warn("Failed to register CPU hotplug notifier...\n");
989 unregister_reboot_notifier(&sdei_reboot_nb);
992 cpu_pm_unregister_notifier(&sdei_pm_nb);
995 sdei_mark_interface_broken();
999 static const struct of_device_id sdei_of_match[] = {
1000 { .compatible = "arm,sdei-1.0" },
1004 static struct platform_driver sdei_driver = {
1008 .of_match_table = sdei_of_match,
1010 .probe = sdei_probe,
1013 static bool __init sdei_present_dt(void)
1015 struct device_node *np, *fw_np;
1017 fw_np = of_find_node_by_name(NULL, "firmware");
1021 np = of_find_matching_node(fw_np, sdei_of_match);
1029 static bool __init sdei_present_acpi(void)
1032 struct platform_device *pdev;
1033 struct acpi_table_header *sdei_table_header;
1038 status = acpi_get_table(ACPI_SIG_SDEI, 0, &sdei_table_header);
1039 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
1040 const char *msg = acpi_format_exception(status);
1042 pr_info("Failed to get ACPI:SDEI table, %s\n", msg);
1044 if (ACPI_FAILURE(status))
1047 pdev = platform_device_register_simple(sdei_driver.driver.name, 0, NULL,
1055 static int __init sdei_init(void)
1057 if (sdei_present_dt() || sdei_present_acpi())
1058 platform_driver_register(&sdei_driver);
1064 * On an ACPI system SDEI needs to be ready before HEST:GHES tries to register
1065 * its events. ACPI is initialised from a subsys_initcall(), GHES is initialised
1066 * by device_initcall(). We want to be called in the middle.
1068 subsys_initcall_sync(sdei_init);
1070 int sdei_event_handler(struct pt_regs *regs,
1071 struct sdei_registered_event *arg)
1074 mm_segment_t orig_addr_limit;
1075 u32 event_num = arg->event_num;
1077 orig_addr_limit = get_fs();
1080 err = arg->callback(event_num, regs, arg->callback_arg);
1082 pr_err_ratelimited("event %u on CPU %u failed with error: %d\n",
1083 event_num, smp_processor_id(), err);
1085 set_fs(orig_addr_limit);
1089 NOKPROBE_SYMBOL(sdei_event_handler);