Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 654 insertions, 0 deletions

diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
new file mode 100644
index 000000000..2344b9d1e
--- /dev/null
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -0,0 +1,654 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * runtime-wrappers.c - Runtime Services function call wrappers
+ *
+ * Implementation summary:
+ * -----------------------
+ * 1. When user/kernel thread requests to execute efi_runtime_service(),
+ * enqueue work to efi_rts_wq.
+ * 2. Caller thread waits for completion until the work is finished
+ * because it's dependent on the return status and execution of
+ * efi_runtime_service().
+ * For instance, get_variable() and get_next_variable().
+ *
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * Split off from arch/x86/platform/efi/efi.c
+ *
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999-2002 Hewlett-Packard Co.
+ * Copyright (C) 2005-2008 Intel Co.
+ * Copyright (C) 2013 SuSE Labs
+ */
+
+#define pr_fmt(fmt)	"efi: " fmt
+
+#include <linux/bug.h>
+#include <linux/efi.h>
+#include <linux/irqflags.h>
+#include <linux/mutex.h>
+#include <linux/semaphore.h>
+#include <linux/stringify.h>
+#include <linux/workqueue.h>
+#include <linux/completion.h>
+
+#include <asm/efi.h>
+
+/*
+ * Wrap around the new efi_call_virt_generic() macros so that the
+ * code doesn't get too cluttered:
+ */
+#define efi_call_virt(f, args...)   \
+	arch_efi_call_virt(efi.runtime, f, args)
+
+union efi_rts_args {
+	struct {
+		efi_time_t 	*time;
+		efi_time_cap_t	*capabilities;
+	} GET_TIME;
+
+	struct {
+		efi_time_t	*time;
+	} SET_TIME;
+
+	struct {
+		efi_bool_t	*enabled;
+		efi_bool_t	*pending;
+		efi_time_t	*time;
+	} GET_WAKEUP_TIME;
+
+	struct {
+		efi_bool_t	enable;
+		efi_time_t	*time;
+	} SET_WAKEUP_TIME;
+
+	struct {
+		efi_char16_t	*name;
+		efi_guid_t	*vendor;
+		u32		*attr;
+		unsigned long	*data_size;
+		void		*data;
+	} GET_VARIABLE;
+
+	struct {
+		unsigned long	*name_size;
+		efi_char16_t	*name;
+		efi_guid_t 	*vendor;
+	} GET_NEXT_VARIABLE;
+
+	struct {
+		efi_char16_t	*name;
+		efi_guid_t	*vendor;
+		u32		attr;
+		unsigned long	data_size;
+		void		*data;
+	} SET_VARIABLE;
+
+	struct {
+		u32		attr;
+		u64		*storage_space;
+		u64		*remaining_space;
+		u64		*max_variable_size;
+	} QUERY_VARIABLE_INFO;
+
+	struct {
+		u32		*high_count;
+	} GET_NEXT_HIGH_MONO_COUNT;
+
+	struct {
+		efi_capsule_header_t **capsules;
+		unsigned long	count;
+		unsigned long	sg_list;
+	} UPDATE_CAPSULE;
+
+	struct {
+		efi_capsule_header_t **capsules;
+		unsigned long	count;
+		u64		*max_size;
+		int		*reset_type;
+	} QUERY_CAPSULE_CAPS;
+
+	struct {
+		efi_status_t	(__efiapi *acpi_prm_handler)(u64, void *);
+		u64		param_buffer_addr;
+		void		*context;
+	} ACPI_PRM_HANDLER;
+};
+
+struct efi_runtime_work efi_rts_work;
+
+/*
+ * Upper bound on how long we wait for a single EFI runtime service
+ * call to finish before declaring firmware wedged. Chosen to be longer
+ * than any plausible legitimate call (including UpdateCapsule on slow
+ * SPI-NOR) while still bounding userspace wait time.
+ */
+#define EFI_RTS_TIMEOUT		(120 * HZ)
+
+/*
+ * efi_queue_work:	Queue EFI runtime service call and wait for completion
+ * @_rts:		EFI runtime service function identifier
+ * @_args:		Arguments to pass to the EFI runtime service
+ *
+ * Accesses to efi_runtime_services() are serialized by a binary
+ * semaphore (efi_runtime_lock) and caller waits until the work is
+ * finished, hence _only_ one work is queued at a time and the caller
+ * thread waits for completion.
+ */
+#define efi_queue_work(_rts, _args...)					\
+	__efi_queue_work(EFI_ ## _rts,					\
+			 &(union efi_rts_args){ ._rts = { _args }})
+
+#ifndef arch_efi_save_flags
+#define arch_efi_save_flags(state_flags)	local_save_flags(state_flags)
+#define arch_efi_restore_flags(state_flags)	local_irq_restore(state_flags)
+#endif
+
+unsigned long efi_call_virt_save_flags(void)
+{
+	unsigned long flags;
+
+	arch_efi_save_flags(flags);
+	return flags;
+}
+
+void efi_call_virt_check_flags(unsigned long flags, const void *caller)
+{
+	unsigned long cur_flags, mismatch;
+
+	cur_flags = efi_call_virt_save_flags();
+
+	mismatch = flags ^ cur_flags;
+	if (!WARN_ON_ONCE(mismatch & ARCH_EFI_IRQ_FLAGS_MASK))
+		return;
+
+	add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_NOW_UNRELIABLE);
+	pr_err_ratelimited(FW_BUG "IRQ flags corrupted (0x%08lx=>0x%08lx) by EFI call from %pS\n",
+			   flags, cur_flags, caller ?: __builtin_return_address(0));
+	arch_efi_restore_flags(flags);
+}
+
+/*
+ * According to section 7.1 of the UEFI spec, Runtime Services are not fully
+ * reentrant, and there are particular combinations of calls that need to be
+ * serialized. (source: UEFI Specification v2.4A)
+ *
+ * Table 31. Rules for Reentry Into Runtime Services
+ * +------------------------------------+-------------------------------+
+ * | If previous call is busy in	| Forbidden to call		|
+ * +------------------------------------+-------------------------------+
+ * | Any				| SetVirtualAddressMap()	|
+ * +------------------------------------+-------------------------------+
+ * | ConvertPointer()			| ConvertPointer()		|
+ * +------------------------------------+-------------------------------+
+ * | SetVariable()			| ResetSystem()			|
+ * | UpdateCapsule()			|				|
+ * | SetTime()				|				|
+ * | SetWakeupTime()			|				|
+ * | GetNextHighMonotonicCount()	|				|
+ * +------------------------------------+-------------------------------+
+ * | GetVariable()			| GetVariable()			|
+ * | GetNextVariableName()		| GetNextVariableName()		|
+ * | SetVariable()			| SetVariable()			|
+ * | QueryVariableInfo()		| QueryVariableInfo()		|
+ * | UpdateCapsule()			| UpdateCapsule()		|
+ * | QueryCapsuleCapabilities()		| QueryCapsuleCapabilities()	|
+ * | GetNextHighMonotonicCount()	| GetNextHighMonotonicCount()	|
+ * +------------------------------------+-------------------------------+
+ * | GetTime()				| GetTime()			|
+ * | SetTime()				| SetTime()			|
+ * | GetWakeupTime()			| GetWakeupTime()		|
+ * | SetWakeupTime()			| SetWakeupTime()		|
+ * +------------------------------------+-------------------------------+
+ *
+ * Due to the fact that the EFI pstore may write to the variable store in
+ * interrupt context, we need to use a lock for at least the groups that
+ * contain SetVariable() and QueryVariableInfo(). That leaves little else, as
+ * none of the remaining functions are actually ever called at runtime.
+ * So let's just use a single lock to serialize all Runtime Services calls.
+ */
+static DEFINE_SEMAPHORE(efi_runtime_lock, 1);
+
+static struct task_struct *efi_runtime_lock_owner __used;
+
+/*
+ * Expose the EFI runtime lock to the UV platform
+ */
+#ifdef CONFIG_X86_UV
+extern struct semaphore __efi_uv_runtime_lock __alias(efi_runtime_lock);
+#endif
+
+/*
+ * Park a worker that must never run efi_rts_wq again: EFI runtime services
+ * have been disabled and its efi_rts_work is abandoned. Loop in schedule()
+ * so a spurious wakeup cannot resume it.
+ */
+void __noreturn efi_rts_park_worker(void)
+{
+	for (;;) {
+		set_current_state(TASK_IDLE);
+		schedule();
+	}
+}
+
+/*
+ * Calls the appropriate efi_runtime_service() with the appropriate
+ * arguments.
+ */
+static void __nocfi efi_call_rts(struct work_struct *work)
+{
+	const union efi_rts_args *args = efi_rts_work.args;
+	efi_status_t status = EFI_NOT_FOUND;
+	unsigned long flags;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		efi_rts_park_worker();
+
+	efi_runtime_lock_owner = current;
+
+	arch_efi_call_virt_setup();
+	flags = efi_call_virt_save_flags();
+
+	switch (efi_rts_work.efi_rts_id) {
+	case EFI_GET_TIME:
+		status = efi_call_virt(get_time,
+				       args->GET_TIME.time,
+				       args->GET_TIME.capabilities);
+		break;
+	case EFI_SET_TIME:
+		status = efi_call_virt(set_time,
+				       args->SET_TIME.time);
+		break;
+	case EFI_GET_WAKEUP_TIME:
+		status = efi_call_virt(get_wakeup_time,
+				       args->GET_WAKEUP_TIME.enabled,
+				       args->GET_WAKEUP_TIME.pending,
+				       args->GET_WAKEUP_TIME.time);
+		break;
+	case EFI_SET_WAKEUP_TIME:
+		status = efi_call_virt(set_wakeup_time,
+				       args->SET_WAKEUP_TIME.enable,
+				       args->SET_WAKEUP_TIME.time);
+		break;
+	case EFI_GET_VARIABLE:
+		status = efi_call_virt(get_variable,
+				       args->GET_VARIABLE.name,
+				       args->GET_VARIABLE.vendor,
+				       args->GET_VARIABLE.attr,
+				       args->GET_VARIABLE.data_size,
+				       args->GET_VARIABLE.data);
+		break;
+	case EFI_GET_NEXT_VARIABLE:
+		status = efi_call_virt(get_next_variable,
+				       args->GET_NEXT_VARIABLE.name_size,
+				       args->GET_NEXT_VARIABLE.name,
+				       args->GET_NEXT_VARIABLE.vendor);
+		break;
+	case EFI_SET_VARIABLE:
+		status = efi_call_virt(set_variable,
+				       args->SET_VARIABLE.name,
+				       args->SET_VARIABLE.vendor,
+				       args->SET_VARIABLE.attr,
+				       args->SET_VARIABLE.data_size,
+				       args->SET_VARIABLE.data);
+		break;
+	case EFI_QUERY_VARIABLE_INFO:
+		status = efi_call_virt(query_variable_info,
+				       args->QUERY_VARIABLE_INFO.attr,
+				       args->QUERY_VARIABLE_INFO.storage_space,
+				       args->QUERY_VARIABLE_INFO.remaining_space,
+				       args->QUERY_VARIABLE_INFO.max_variable_size);
+		break;
+	case EFI_GET_NEXT_HIGH_MONO_COUNT:
+		status = efi_call_virt(get_next_high_mono_count,
+				       args->GET_NEXT_HIGH_MONO_COUNT.high_count);
+		break;
+	case EFI_UPDATE_CAPSULE:
+		status = efi_call_virt(update_capsule,
+				       args->UPDATE_CAPSULE.capsules,
+				       args->UPDATE_CAPSULE.count,
+				       args->UPDATE_CAPSULE.sg_list);
+		break;
+	case EFI_QUERY_CAPSULE_CAPS:
+		status = efi_call_virt(query_capsule_caps,
+				       args->QUERY_CAPSULE_CAPS.capsules,
+				       args->QUERY_CAPSULE_CAPS.count,
+				       args->QUERY_CAPSULE_CAPS.max_size,
+				       args->QUERY_CAPSULE_CAPS.reset_type);
+		break;
+	case EFI_ACPI_PRM_HANDLER:
+#ifdef CONFIG_ACPI_PRMT
+		status = arch_efi_call_virt(args, ACPI_PRM_HANDLER.acpi_prm_handler,
+					    args->ACPI_PRM_HANDLER.param_buffer_addr,
+					    args->ACPI_PRM_HANDLER.context);
+		break;
+#endif
+	default:
+		/*
+		 * Ideally, we should never reach here because a caller of this
+		 * function should have put the right efi_runtime_service()
+		 * function identifier into efi_rts_work->efi_rts_id
+		 */
+		pr_err("Requested executing invalid EFI Runtime Service.\n");
+	}
+
+	efi_call_virt_check_flags(flags, efi_rts_work.caller);
+	arch_efi_call_virt_teardown();
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES))
+		efi_rts_park_worker();
+
+	efi_rts_work.status = status;
+	complete(&efi_rts_work.efi_rts_comp);
+	efi_runtime_lock_owner = NULL;
+}
+
+static efi_status_t __efi_queue_work(enum efi_rts_ids id,
+				     union efi_rts_args *args)
+{
+	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
+		pr_warn_once("EFI Runtime Services are disabled!\n");
+		return EFI_DEVICE_ERROR;
+	}
+
+	efi_rts_work.efi_rts_id = id;
+	efi_rts_work.args = args;
+	efi_rts_work.caller = __builtin_return_address(0);
+	efi_rts_work.status = EFI_ABORTED;
+
+	init_completion(&efi_rts_work.efi_rts_comp);
+	INIT_WORK(&efi_rts_work.work, efi_call_rts);
+
+	/*
+	 * queue_work() returns 0 if work was already on queue,
+	 * _ideally_ this should never happen.
+	 */
+	if (!queue_work(efi_rts_wq, &efi_rts_work.work)) {
+		pr_err("Failed to queue work to efi_rts_wq.\n");
+		goto exit;
+	}
+
+	if (!wait_for_completion_timeout(&efi_rts_work.efi_rts_comp,
+					 EFI_RTS_TIMEOUT)) {
+		pr_err("EFI runtime service %d wedged in firmware; disabling EFI runtime services\n",
+		       id);
+		clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+		return EFI_ABORTED;
+	}
+
+	WARN_ON_ONCE(efi_rts_work.status == EFI_ABORTED);
+exit:
+	efi_rts_work.efi_rts_id = EFI_NONE;
+	return efi_rts_work.status;
+}
+
+static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(GET_TIME, tm, tc);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_set_time(efi_time_t *tm)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(SET_TIME, tm);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
+					     efi_bool_t *pending,
+					     efi_time_t *tm)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(GET_WAKEUP_TIME, enabled, pending, tm);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(SET_WAKEUP_TIME, enabled, tm);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_get_variable(efi_char16_t *name,
+					  efi_guid_t *vendor,
+					  u32 *attr,
+					  unsigned long *data_size,
+					  void *data)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(GET_VARIABLE, name, vendor, attr, data_size,
+				data);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
+					       efi_char16_t *name,
+					       efi_guid_t *vendor)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(GET_NEXT_VARIABLE, name_size, name, vendor);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_set_variable(efi_char16_t *name,
+					  efi_guid_t *vendor,
+					  u32 attr,
+					  unsigned long data_size,
+					  void *data)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(SET_VARIABLE, name, vendor, attr, data_size,
+				data);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t __nocfi
+virt_efi_set_variable_nb(efi_char16_t *name, efi_guid_t *vendor, u32 attr,
+			 unsigned long data_size, void *data)
+{
+	efi_status_t status;
+
+	if (down_trylock(&efi_runtime_lock))
+		return EFI_NOT_READY;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
+		up(&efi_runtime_lock);
+		return EFI_DEVICE_ERROR;
+	}
+
+	efi_runtime_lock_owner = current;
+	status = efi_call_virt_pointer(efi.runtime, set_variable, name, vendor,
+				       attr, data_size, data);
+	efi_runtime_lock_owner = NULL;
+	up(&efi_runtime_lock);
+	return status;
+}
+
+
+static efi_status_t virt_efi_query_variable_info(u32 attr,
+						 u64 *storage_space,
+						 u64 *remaining_space,
+						 u64 *max_variable_size)
+{
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(QUERY_VARIABLE_INFO, attr, storage_space,
+				remaining_space, max_variable_size);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t __nocfi
+virt_efi_query_variable_info_nb(u32 attr, u64 *storage_space,
+				u64 *remaining_space, u64 *max_variable_size)
+{
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	if (down_trylock(&efi_runtime_lock))
+		return EFI_NOT_READY;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
+		up(&efi_runtime_lock);
+		return EFI_DEVICE_ERROR;
+	}
+
+	efi_runtime_lock_owner = current;
+	status = efi_call_virt_pointer(efi.runtime, query_variable_info, attr,
+				       storage_space, remaining_space,
+				       max_variable_size);
+	efi_runtime_lock_owner = NULL;
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(GET_NEXT_HIGH_MONO_COUNT, count);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static void __nocfi
+virt_efi_reset_system(int reset_type, efi_status_t status,
+		      unsigned long data_size, efi_char16_t *data)
+{
+	if (down_trylock(&efi_runtime_lock)) {
+		pr_warn("failed to invoke the reset_system() runtime service:\n"
+			"could not get exclusive access to the firmware\n");
+		return;
+	}
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
+		pr_warn("EFI Runtime Services are disabled, not invoking reset_system()\n");
+		up(&efi_runtime_lock);
+		return;
+	}
+
+	efi_runtime_lock_owner = current;
+	arch_efi_call_virt_setup();
+	efi_rts_work.efi_rts_id = EFI_RESET_SYSTEM;
+	arch_efi_call_virt(efi.runtime, reset_system, reset_type, status,
+			   data_size, data);
+	arch_efi_call_virt_teardown();
+	efi_runtime_lock_owner = NULL;
+	up(&efi_runtime_lock);
+}
+
+static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
+					    unsigned long count,
+					    unsigned long sg_list)
+{
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(UPDATE_CAPSULE, capsules, count, sg_list);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
+						unsigned long count,
+						u64 *max_size,
+						int *reset_type)
+{
+	efi_status_t status;
+
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(QUERY_CAPSULE_CAPS, capsules, count,
+				max_size, reset_type);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+void __init efi_native_runtime_setup(void)
+{
+	efi.get_time			    = virt_efi_get_time;
+	efi.set_time			    = virt_efi_set_time;
+	efi.get_wakeup_time		    = virt_efi_get_wakeup_time;
+	efi.set_wakeup_time		    = virt_efi_set_wakeup_time;
+	efi.get_variable		    = virt_efi_get_variable;
+	efi.get_next_variable		    = virt_efi_get_next_variable;
+	efi.set_variable		    = virt_efi_set_variable;
+	efi.set_variable_nonblocking	    = virt_efi_set_variable_nb;
+	efi.get_next_high_mono_count	    = virt_efi_get_next_high_mono_count;
+	efi.reset_system 		    = virt_efi_reset_system;
+	efi.query_variable_info		    = virt_efi_query_variable_info;
+	efi.query_variable_info_nonblocking = virt_efi_query_variable_info_nb;
+	efi.update_capsule		    = virt_efi_update_capsule;
+	efi.query_capsule_caps		    = virt_efi_query_capsule_caps;
+}
+
+#ifdef CONFIG_ACPI_PRMT
+
+efi_status_t
+efi_call_acpi_prm_handler(efi_status_t (__efiapi *handler_addr)(u64, void *),
+			  u64 param_buffer_addr, void *context)
+{
+	efi_status_t status;
+
+	if (down_interruptible(&efi_runtime_lock))
+		return EFI_ABORTED;
+	status = efi_queue_work(ACPI_PRM_HANDLER, handler_addr,
+				param_buffer_addr, context);
+	up(&efi_runtime_lock);
+	return status;
+}
+
+#endif
+
+void efi_runtime_assert_lock_held(void)
+{
+	WARN_ON(efi_runtime_lock_owner != current);
+}