Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 1045 insertions, 0 deletions

diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
new file mode 100644
index 000000000..dd4a99f09
--- /dev/null
+++ b/drivers/acpi/sysfs.c
@@ -0,0 +1,1045 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * sysfs.c - ACPI sysfs interface to userspace.
+ */
+
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#include <linux/acpi.h>
+#include <linux/bitmap.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/kstrtox.h>
+#include <linux/moduleparam.h>
+
+#include "internal.h"
+
+#ifdef CONFIG_ACPI_DEBUG
+/*
+ * ACPI debug sysfs I/F, including:
+ * /sys/module/acpi/parameters/debug_layer
+ * /sys/module/acpi/parameters/debug_level
+ * /sys/module/acpi/parameters/trace_method_name
+ * /sys/module/acpi/parameters/trace_state
+ * /sys/module/acpi/parameters/trace_debug_layer
+ * /sys/module/acpi/parameters/trace_debug_level
+ */
+
+struct acpi_dlayer {
+	const char *name;
+	unsigned long value;
+};
+struct acpi_dlevel {
+	const char *name;
+	unsigned long value;
+};
+#define ACPI_DEBUG_INIT(v)	{ .name = #v, .value = v }
+
+static const struct acpi_dlayer acpi_debug_layers[] = {
+	ACPI_DEBUG_INIT(ACPI_UTILITIES),
+	ACPI_DEBUG_INIT(ACPI_HARDWARE),
+	ACPI_DEBUG_INIT(ACPI_EVENTS),
+	ACPI_DEBUG_INIT(ACPI_TABLES),
+	ACPI_DEBUG_INIT(ACPI_NAMESPACE),
+	ACPI_DEBUG_INIT(ACPI_PARSER),
+	ACPI_DEBUG_INIT(ACPI_DISPATCHER),
+	ACPI_DEBUG_INIT(ACPI_EXECUTER),
+	ACPI_DEBUG_INIT(ACPI_RESOURCES),
+	ACPI_DEBUG_INIT(ACPI_CA_DEBUGGER),
+	ACPI_DEBUG_INIT(ACPI_OS_SERVICES),
+	ACPI_DEBUG_INIT(ACPI_CA_DISASSEMBLER),
+	ACPI_DEBUG_INIT(ACPI_COMPILER),
+	ACPI_DEBUG_INIT(ACPI_TOOLS),
+};
+
+static const struct acpi_dlevel acpi_debug_levels[] = {
+	ACPI_DEBUG_INIT(ACPI_LV_INIT),
+	ACPI_DEBUG_INIT(ACPI_LV_DEBUG_OBJECT),
+	ACPI_DEBUG_INIT(ACPI_LV_INFO),
+	ACPI_DEBUG_INIT(ACPI_LV_REPAIR),
+	ACPI_DEBUG_INIT(ACPI_LV_TRACE_POINT),
+
+	ACPI_DEBUG_INIT(ACPI_LV_INIT_NAMES),
+	ACPI_DEBUG_INIT(ACPI_LV_PARSE),
+	ACPI_DEBUG_INIT(ACPI_LV_LOAD),
+	ACPI_DEBUG_INIT(ACPI_LV_DISPATCH),
+	ACPI_DEBUG_INIT(ACPI_LV_EXEC),
+	ACPI_DEBUG_INIT(ACPI_LV_NAMES),
+	ACPI_DEBUG_INIT(ACPI_LV_OPREGION),
+	ACPI_DEBUG_INIT(ACPI_LV_BFIELD),
+	ACPI_DEBUG_INIT(ACPI_LV_TABLES),
+	ACPI_DEBUG_INIT(ACPI_LV_VALUES),
+	ACPI_DEBUG_INIT(ACPI_LV_OBJECTS),
+	ACPI_DEBUG_INIT(ACPI_LV_RESOURCES),
+	ACPI_DEBUG_INIT(ACPI_LV_USER_REQUESTS),
+	ACPI_DEBUG_INIT(ACPI_LV_PACKAGE),
+
+	ACPI_DEBUG_INIT(ACPI_LV_ALLOCATIONS),
+	ACPI_DEBUG_INIT(ACPI_LV_FUNCTIONS),
+	ACPI_DEBUG_INIT(ACPI_LV_OPTIMIZATIONS),
+
+	ACPI_DEBUG_INIT(ACPI_LV_MUTEX),
+	ACPI_DEBUG_INIT(ACPI_LV_THREADS),
+	ACPI_DEBUG_INIT(ACPI_LV_IO),
+	ACPI_DEBUG_INIT(ACPI_LV_INTERRUPTS),
+
+	ACPI_DEBUG_INIT(ACPI_LV_AML_DISASSEMBLE),
+	ACPI_DEBUG_INIT(ACPI_LV_VERBOSE_INFO),
+	ACPI_DEBUG_INIT(ACPI_LV_FULL_TABLES),
+	ACPI_DEBUG_INIT(ACPI_LV_EVENTS),
+};
+
+static int param_get_debug_layer(char *buffer, const struct kernel_param *kp)
+{
+	int result = 0;
+	int i;
+
+	result = sprintf(buffer, "%-25s\tHex        SET\n", "Description");
+
+	for (i = 0; i < ARRAY_SIZE(acpi_debug_layers); i++) {
+		result += sprintf(buffer + result, "%-25s\t0x%08lX [%c]\n",
+				  acpi_debug_layers[i].name,
+				  acpi_debug_layers[i].value,
+				  (acpi_dbg_layer & acpi_debug_layers[i].value)
+				  ? '*' : ' ');
+	}
+	result +=
+	    sprintf(buffer + result, "%-25s\t0x%08X [%c]\n", "ACPI_ALL_DRIVERS",
+		    ACPI_ALL_DRIVERS,
+		    (acpi_dbg_layer & ACPI_ALL_DRIVERS) ==
+		    ACPI_ALL_DRIVERS ? '*' : (acpi_dbg_layer & ACPI_ALL_DRIVERS)
+		    == 0 ? ' ' : '-');
+	result +=
+	    sprintf(buffer + result,
+		    "--\ndebug_layer = 0x%08X ( * = enabled)\n",
+		    acpi_dbg_layer);
+
+	return result;
+}
+
+static int param_get_debug_level(char *buffer, const struct kernel_param *kp)
+{
+	int result = 0;
+	int i;
+
+	result = sprintf(buffer, "%-25s\tHex        SET\n", "Description");
+
+	for (i = 0; i < ARRAY_SIZE(acpi_debug_levels); i++) {
+		result += sprintf(buffer + result, "%-25s\t0x%08lX [%c]\n",
+				  acpi_debug_levels[i].name,
+				  acpi_debug_levels[i].value,
+				  (acpi_dbg_level & acpi_debug_levels[i].value)
+				  ? '*' : ' ');
+	}
+	result +=
+	    sprintf(buffer + result, "--\ndebug_level = 0x%08X (* = enabled)\n",
+		    acpi_dbg_level);
+
+	return result;
+}
+
+static const struct kernel_param_ops param_ops_debug_layer = {
+	.set = param_set_uint,
+	.get = param_get_debug_layer,
+};
+
+static const struct kernel_param_ops param_ops_debug_level = {
+	.set = param_set_uint,
+	.get = param_get_debug_level,
+};
+
+module_param_cb(debug_layer, &param_ops_debug_layer, &acpi_dbg_layer, 0644);
+module_param_cb(debug_level, &param_ops_debug_level, &acpi_dbg_level, 0644);
+
+static char trace_method_name[1024];
+
+static int param_set_trace_method_name(const char *val,
+				       const struct kernel_param *kp)
+{
+	u32 saved_flags = 0;
+	bool is_abs_path = true;
+
+	if (*val != '\\')
+		is_abs_path = false;
+
+	if ((is_abs_path && strlen(val) > 1023) ||
+	    (!is_abs_path && strlen(val) > 1022)) {
+		pr_err("%s: string parameter too long\n", kp->name);
+		return -ENOSPC;
+	}
+
+	/*
+	 * It's not safe to update acpi_gbl_trace_method_name without
+	 * having the tracer stopped, so we save the original tracer
+	 * state and disable it.
+	 */
+	saved_flags = acpi_gbl_trace_flags;
+	(void)acpi_debug_trace(NULL,
+			       acpi_gbl_trace_dbg_level,
+			       acpi_gbl_trace_dbg_layer,
+			       0);
+
+	/* This is a hack.  We can't kmalloc in early boot. */
+	if (is_abs_path)
+		strcpy(trace_method_name, val);
+	else {
+		trace_method_name[0] = '\\';
+		strcpy(trace_method_name+1, val);
+	}
+
+	/* Restore the original tracer state */
+	(void)acpi_debug_trace(trace_method_name,
+			       acpi_gbl_trace_dbg_level,
+			       acpi_gbl_trace_dbg_layer,
+			       saved_flags);
+
+	return 0;
+}
+
+static int param_get_trace_method_name(char *buffer, const struct kernel_param *kp)
+{
+	return sysfs_emit(buffer, "%s\n", acpi_gbl_trace_method_name);
+}
+
+static const struct kernel_param_ops param_ops_trace_method = {
+	.set = param_set_trace_method_name,
+	.get = param_get_trace_method_name,
+};
+
+static const struct kernel_param_ops param_ops_trace_attrib = {
+	.set = param_set_uint,
+	.get = param_get_uint,
+};
+
+module_param_cb(trace_method_name, &param_ops_trace_method, &trace_method_name, 0644);
+module_param_cb(trace_debug_layer, &param_ops_trace_attrib, &acpi_gbl_trace_dbg_layer, 0644);
+module_param_cb(trace_debug_level, &param_ops_trace_attrib, &acpi_gbl_trace_dbg_level, 0644);
+
+static int param_set_trace_state(const char *val,
+				 const struct kernel_param *kp)
+{
+	acpi_status status;
+	const char *method = trace_method_name;
+	u32 flags = 0;
+
+/* So "xxx-once" comparison should go prior than "xxx" comparison */
+#define acpi_compare_param(val, key)	\
+	strncmp((val), (key), sizeof(key) - 1)
+
+	if (!acpi_compare_param(val, "enable")) {
+		method = NULL;
+		flags = ACPI_TRACE_ENABLED;
+	} else if (!acpi_compare_param(val, "disable"))
+		method = NULL;
+	else if (!acpi_compare_param(val, "method-once"))
+		flags = ACPI_TRACE_ENABLED | ACPI_TRACE_ONESHOT;
+	else if (!acpi_compare_param(val, "method"))
+		flags = ACPI_TRACE_ENABLED;
+	else if (!acpi_compare_param(val, "opcode-once"))
+		flags = ACPI_TRACE_ENABLED | ACPI_TRACE_ONESHOT | ACPI_TRACE_OPCODE;
+	else if (!acpi_compare_param(val, "opcode"))
+		flags = ACPI_TRACE_ENABLED | ACPI_TRACE_OPCODE;
+	else
+		return -EINVAL;
+
+	status = acpi_debug_trace(method,
+				  acpi_gbl_trace_dbg_level,
+				  acpi_gbl_trace_dbg_layer,
+				  flags);
+	if (ACPI_FAILURE(status))
+		return -EBUSY;
+
+	return 0;
+}
+
+static int param_get_trace_state(char *buffer, const struct kernel_param *kp)
+{
+	if (!(acpi_gbl_trace_flags & ACPI_TRACE_ENABLED))
+		return sprintf(buffer, "disable\n");
+	if (!acpi_gbl_trace_method_name)
+		return sprintf(buffer, "enable\n");
+	if (acpi_gbl_trace_flags & ACPI_TRACE_ONESHOT)
+		return sprintf(buffer, "method-once\n");
+	else
+		return sprintf(buffer, "method\n");
+}
+
+module_param_call(trace_state, param_set_trace_state, param_get_trace_state,
+		  NULL, 0644);
+#endif /* CONFIG_ACPI_DEBUG */
+
+
+/* /sys/module/acpi/parameters/aml_debug_output */
+
+module_param_named(aml_debug_output, acpi_gbl_enable_aml_debug_object,
+		   byte, 0644);
+MODULE_PARM_DESC(aml_debug_output,
+		 "To enable/disable the ACPI Debug Object output.");
+
+/* /sys/module/acpi/parameters/acpica_version */
+static int param_get_acpica_version(char *buffer,
+				    const struct kernel_param *kp)
+{
+	int result;
+
+	result = sprintf(buffer, "%x\n", ACPI_CA_VERSION);
+
+	return result;
+}
+
+module_param_call(acpica_version, NULL, param_get_acpica_version, NULL, 0444);
+
+/*
+ * ACPI table sysfs I/F:
+ * /sys/firmware/acpi/tables/
+ * /sys/firmware/acpi/tables/data/
+ * /sys/firmware/acpi/tables/dynamic/
+ */
+
+static LIST_HEAD(acpi_table_attr_list);
+static struct kobject *tables_kobj;
+static struct kobject *tables_data_kobj;
+static struct kobject *dynamic_tables_kobj;
+static struct kobject *hotplug_kobj;
+
+#define ACPI_MAX_TABLE_INSTANCES	999
+#define ACPI_INST_SIZE			4 /* including trailing 0 */
+
+struct acpi_table_attr {
+	struct bin_attribute attr;
+	char name[ACPI_NAMESEG_SIZE];
+	int instance;
+	char filename[ACPI_NAMESEG_SIZE+ACPI_INST_SIZE];
+	struct list_head node;
+};
+
+struct acpi_data_attr {
+	struct bin_attribute attr;
+	u64	addr;
+	char filename[ACPI_NAMESEG_SIZE+ACPI_INST_SIZE];
+};
+
+static ssize_t acpi_table_show(struct file *filp, struct kobject *kobj,
+			       const struct bin_attribute *bin_attr, char *buf,
+			       loff_t offset, size_t count)
+{
+	struct acpi_table_attr *table_attr =
+	    container_of(bin_attr, struct acpi_table_attr, attr);
+	struct acpi_table_header *table_header = NULL;
+	acpi_status status;
+	ssize_t rc;
+
+	status = acpi_get_table(table_attr->name, table_attr->instance,
+				&table_header);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	rc = memory_read_from_buffer(buf, count, &offset, table_header,
+			table_header->length);
+	acpi_put_table(table_header);
+	return rc;
+}
+
+static int acpi_table_attr_init(struct kobject *tables_obj,
+				struct acpi_table_attr *table_attr,
+				struct acpi_table_header *table_header)
+{
+	struct acpi_table_header *header = NULL;
+	struct acpi_table_attr *attr = NULL;
+	char instance_str[ACPI_INST_SIZE];
+
+	sysfs_attr_init(&table_attr->attr.attr);
+	ACPI_COPY_NAMESEG(table_attr->name, table_header->signature);
+
+	list_for_each_entry(attr, &acpi_table_attr_list, node) {
+		if (ACPI_COMPARE_NAMESEG(table_attr->name, attr->name))
+			if (table_attr->instance < attr->instance)
+				table_attr->instance = attr->instance;
+	}
+	table_attr->instance++;
+	if (table_attr->instance > ACPI_MAX_TABLE_INSTANCES) {
+		pr_warn("%4.4s: too many table instances\n", table_attr->name);
+		return -ERANGE;
+	}
+
+	ACPI_COPY_NAMESEG(table_attr->filename, table_header->signature);
+	table_attr->filename[ACPI_NAMESEG_SIZE] = '\0';
+	if (table_attr->instance > 1 || (table_attr->instance == 1 &&
+					 !acpi_get_table
+					 (table_header->signature, 2, &header))) {
+		snprintf(instance_str, sizeof(instance_str), "%u",
+			 table_attr->instance);
+		strcat(table_attr->filename, instance_str);
+	}
+
+	table_attr->attr.size = table_header->length;
+	table_attr->attr.read = acpi_table_show;
+	table_attr->attr.attr.name = table_attr->filename;
+	table_attr->attr.attr.mode = 0400;
+
+	return sysfs_create_bin_file(tables_obj, &table_attr->attr);
+}
+
+acpi_status acpi_sysfs_table_handler(u32 event, void *table, void *context)
+{
+	struct acpi_table_attr *table_attr;
+
+	switch (event) {
+	case ACPI_TABLE_EVENT_INSTALL:
+		table_attr = kzalloc_obj(*table_attr);
+		if (!table_attr)
+			return AE_NO_MEMORY;
+
+		if (acpi_table_attr_init(dynamic_tables_kobj,
+					 table_attr, table)) {
+			kfree(table_attr);
+			return AE_ERROR;
+		}
+		list_add_tail(&table_attr->node, &acpi_table_attr_list);
+		break;
+	case ACPI_TABLE_EVENT_LOAD:
+	case ACPI_TABLE_EVENT_UNLOAD:
+	case ACPI_TABLE_EVENT_UNINSTALL:
+		/*
+		 * we do not need to do anything right now
+		 * because the table is not deleted from the
+		 * global table list when unloading it.
+		 */
+		break;
+	default:
+		return AE_BAD_PARAMETER;
+	}
+	return AE_OK;
+}
+
+static ssize_t acpi_data_show(struct file *filp, struct kobject *kobj,
+			      const struct bin_attribute *bin_attr, char *buf,
+			      loff_t offset, size_t count)
+{
+	struct acpi_data_attr *data_attr;
+	void __iomem *base;
+	ssize_t size;
+
+	data_attr = container_of(bin_attr, struct acpi_data_attr, attr);
+	size = data_attr->attr.size;
+
+	if (offset < 0)
+		return -EINVAL;
+
+	if (offset >= size)
+		return 0;
+
+	if (count > size - offset)
+		count = size - offset;
+
+	base = acpi_os_map_iomem(data_attr->addr, size);
+	if (!base)
+		return -ENOMEM;
+
+	memcpy_fromio(buf, base + offset, count);
+
+	acpi_os_unmap_iomem(base, size);
+
+	return count;
+}
+
+static int acpi_bert_data_init(void *th, struct acpi_data_attr *data_attr)
+{
+	struct acpi_table_bert *bert = th;
+
+	if (bert->header.length < sizeof(struct acpi_table_bert) ||
+	    bert->region_length < sizeof(struct acpi_bert_region)) {
+		kfree(data_attr);
+		return -EINVAL;
+	}
+	data_attr->addr = bert->address;
+	data_attr->attr.size = bert->region_length;
+
+	return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr);
+}
+
+static int acpi_ccel_data_init(void *th, struct acpi_data_attr *data_attr)
+{
+	struct acpi_table_ccel *ccel = th;
+
+	if (ccel->header.length < sizeof(struct acpi_table_ccel) ||
+	    !ccel->log_area_start_address || !ccel->log_area_minimum_length) {
+		kfree(data_attr);
+		return -EINVAL;
+	}
+	data_attr->addr = ccel->log_area_start_address;
+	data_attr->attr.size = ccel->log_area_minimum_length;
+
+	return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr);
+}
+
+static struct acpi_data_obj {
+	char *name;
+	int (*fn)(void *, struct acpi_data_attr *);
+} acpi_data_objs[] = {
+	{ ACPI_SIG_BERT, acpi_bert_data_init },
+	{ ACPI_SIG_CCEL, acpi_ccel_data_init },
+};
+
+#define NUM_ACPI_DATA_OBJS ARRAY_SIZE(acpi_data_objs)
+
+static int acpi_table_data_init(struct acpi_table_header *th, struct acpi_table_attr *table_attr)
+{
+	struct acpi_data_attr *data_attr;
+	int i;
+
+	for (i = 0; i < NUM_ACPI_DATA_OBJS; i++) {
+		if (ACPI_COMPARE_NAMESEG(th->signature, acpi_data_objs[i].name)) {
+			data_attr = kzalloc_obj(*data_attr);
+			if (!data_attr)
+				return -ENOMEM;
+			sysfs_attr_init(&data_attr->attr.attr);
+			data_attr->attr.read = acpi_data_show;
+			data_attr->attr.attr.mode = 0400;
+			strscpy(data_attr->filename, table_attr->filename);
+			data_attr->attr.attr.name = data_attr->filename;
+			return acpi_data_objs[i].fn(th, data_attr);
+		}
+	}
+	return 0;
+}
+
+static int acpi_tables_sysfs_init(void)
+{
+	struct acpi_table_attr *table_attr;
+	struct acpi_table_header *table_header = NULL;
+	int table_index;
+	acpi_status status;
+	int ret;
+
+	tables_kobj = kobject_create_and_add("tables", acpi_kobj);
+	if (!tables_kobj)
+		goto err;
+
+	tables_data_kobj = kobject_create_and_add("data", tables_kobj);
+	if (!tables_data_kobj)
+		goto err_tables_data;
+
+	dynamic_tables_kobj = kobject_create_and_add("dynamic", tables_kobj);
+	if (!dynamic_tables_kobj)
+		goto err_dynamic_tables;
+
+	for (table_index = 0;; table_index++) {
+		status = acpi_get_table_by_index(table_index, &table_header);
+
+		if (status == AE_BAD_PARAMETER)
+			break;
+
+		if (ACPI_FAILURE(status))
+			continue;
+
+		table_attr = kzalloc_obj(*table_attr);
+		if (!table_attr)
+			return -ENOMEM;
+
+		ret = acpi_table_attr_init(tables_kobj,
+					   table_attr, table_header);
+		if (ret) {
+			kfree(table_attr);
+			return ret;
+		}
+		list_add_tail(&table_attr->node, &acpi_table_attr_list);
+		acpi_table_data_init(table_header, table_attr);
+	}
+
+	kobject_uevent(tables_kobj, KOBJ_ADD);
+	kobject_uevent(tables_data_kobj, KOBJ_ADD);
+	kobject_uevent(dynamic_tables_kobj, KOBJ_ADD);
+
+	return 0;
+err_dynamic_tables:
+	kobject_put(tables_data_kobj);
+err_tables_data:
+	kobject_put(tables_kobj);
+err:
+	return -ENOMEM;
+}
+
+/*
+ * Detailed ACPI IRQ counters:
+ * /sys/firmware/acpi/interrupts/
+ */
+
+u32 acpi_irq_handled;
+u32 acpi_irq_not_handled;
+
+#define COUNT_GPE 0
+#define COUNT_SCI 1		/* acpi_irq_handled */
+#define COUNT_SCI_NOT 2		/* acpi_irq_not_handled */
+#define COUNT_ERROR 3		/* other */
+#define NUM_COUNTERS_EXTRA 4
+
+struct event_counter {
+	u32 count;
+	u32 flags;
+};
+
+static struct event_counter *all_counters;
+static u32 num_gpes;
+static u32 num_counters;
+static struct attribute **all_attrs;
+static u32 acpi_gpe_count;
+
+static struct attribute_group interrupt_stats_attr_group = {
+	.name = "interrupts",
+};
+
+static struct kobj_attribute *counter_attrs;
+
+static void delete_gpe_attr_array(void)
+{
+	struct event_counter *tmp = all_counters;
+
+	all_counters = NULL;
+	kfree(tmp);
+
+	if (counter_attrs) {
+		int i;
+
+		for (i = 0; i < num_gpes; i++)
+			kfree(counter_attrs[i].attr.name);
+
+		kfree(counter_attrs);
+	}
+	kfree(all_attrs);
+}
+
+static void gpe_count(u32 gpe_number)
+{
+	acpi_gpe_count++;
+
+	if (!all_counters)
+		return;
+
+	if (gpe_number < num_gpes)
+		all_counters[gpe_number].count++;
+	else
+		all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS +
+			     COUNT_ERROR].count++;
+}
+
+static void fixed_event_count(u32 event_number)
+{
+	if (!all_counters)
+		return;
+
+	if (event_number < ACPI_NUM_FIXED_EVENTS)
+		all_counters[num_gpes + event_number].count++;
+	else
+		all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS +
+			     COUNT_ERROR].count++;
+}
+
+static void acpi_global_event_handler(u32 event_type, acpi_handle device,
+	u32 event_number, void *context)
+{
+	if (event_type == ACPI_EVENT_TYPE_GPE) {
+		gpe_count(event_number);
+		pr_debug("GPE event 0x%02x\n", event_number);
+	} else if (event_type == ACPI_EVENT_TYPE_FIXED) {
+		fixed_event_count(event_number);
+		pr_debug("Fixed event 0x%02x\n", event_number);
+	} else {
+		pr_debug("Other event 0x%02x\n", event_number);
+	}
+}
+
+static int get_status(u32 index, acpi_event_status *ret,
+		      acpi_handle *handle)
+{
+	acpi_status status;
+
+	if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
+		return -EINVAL;
+
+	if (index < num_gpes) {
+		status = acpi_get_gpe_device(index, handle);
+		if (ACPI_FAILURE(status)) {
+			pr_warn("Invalid GPE 0x%x", index);
+			return -ENXIO;
+		}
+		status = acpi_get_gpe_status(*handle, index, ret);
+	} else {
+		status = acpi_get_event_status(index - num_gpes, ret);
+	}
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return 0;
+}
+
+static ssize_t counter_show(struct kobject *kobj,
+			    struct kobj_attribute *attr, char *buf)
+{
+	int index = attr - counter_attrs;
+	int size;
+	acpi_handle handle;
+	acpi_event_status status;
+	int result = 0;
+
+	all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI].count =
+	    acpi_irq_handled;
+	all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI_NOT].count =
+	    acpi_irq_not_handled;
+	all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE].count =
+	    acpi_gpe_count;
+	size = sysfs_emit(buf, "%8u", all_counters[index].count);
+
+	/* "gpe_all" or "sci" */
+	if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
+		goto end;
+
+	result = get_status(index, &status, &handle);
+	if (result)
+		goto end;
+
+	if (status & ACPI_EVENT_FLAG_ENABLE_SET)
+		size += sysfs_emit_at(buf, size, "  EN");
+	else
+		size += sysfs_emit_at(buf, size, "    ");
+	if (status & ACPI_EVENT_FLAG_STATUS_SET)
+		size += sysfs_emit_at(buf, size, " STS");
+	else
+		size += sysfs_emit_at(buf, size, "    ");
+
+	if (!(status & ACPI_EVENT_FLAG_HAS_HANDLER))
+		size += sysfs_emit_at(buf, size, " invalid     ");
+	else if (status & ACPI_EVENT_FLAG_ENABLED)
+		size += sysfs_emit_at(buf, size, " enabled     ");
+	else if (status & ACPI_EVENT_FLAG_WAKE_ENABLED)
+		size += sysfs_emit_at(buf, size, " wake_enabled");
+	else
+		size += sysfs_emit_at(buf, size, " disabled    ");
+	if (status & ACPI_EVENT_FLAG_MASKED)
+		size += sysfs_emit_at(buf, size, " masked  ");
+	else
+		size += sysfs_emit_at(buf, size, " unmasked");
+
+end:
+	size += sysfs_emit_at(buf, size, "\n");
+	return result ? result : size;
+}
+
+/*
+ * counter_set() sets the specified counter.
+ * setting the total "sci" file to any value clears all counters.
+ * enable/disable/clear a gpe/fixed event in user space.
+ */
+static ssize_t counter_set(struct kobject *kobj,
+			   struct kobj_attribute *attr, const char *buf,
+			   size_t size)
+{
+	int index = attr - counter_attrs;
+	acpi_event_status status;
+	acpi_handle handle;
+	int result = 0;
+	unsigned long tmp;
+
+	if (index == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI) {
+		int i;
+		for (i = 0; i < num_counters; ++i)
+			all_counters[i].count = 0;
+		acpi_gpe_count = 0;
+		acpi_irq_handled = 0;
+		acpi_irq_not_handled = 0;
+		goto end;
+	}
+
+	/* show the event status for both GPEs and Fixed Events */
+	result = get_status(index, &status, &handle);
+	if (result)
+		goto end;
+
+	if (!(status & ACPI_EVENT_FLAG_HAS_HANDLER)) {
+		pr_warn("Can not change Invalid GPE/Fixed Event status\n");
+		return -EINVAL;
+	}
+
+	if (index < num_gpes) {
+		if (!strcmp(buf, "disable\n") &&
+		    (status & ACPI_EVENT_FLAG_ENABLED))
+			result = acpi_disable_gpe(handle, index);
+		else if (!strcmp(buf, "enable\n") &&
+			 !(status & ACPI_EVENT_FLAG_ENABLED))
+			result = acpi_enable_gpe(handle, index);
+		else if (!strcmp(buf, "clear\n") &&
+			 (status & ACPI_EVENT_FLAG_STATUS_SET))
+			result = acpi_clear_gpe(handle, index);
+		else if (!strcmp(buf, "mask\n"))
+			result = acpi_mask_gpe(handle, index, TRUE);
+		else if (!strcmp(buf, "unmask\n"))
+			result = acpi_mask_gpe(handle, index, FALSE);
+		else if (!kstrtoul(buf, 0, &tmp))
+			all_counters[index].count = tmp;
+		else
+			result = -EINVAL;
+	} else if (index < num_gpes + ACPI_NUM_FIXED_EVENTS) {
+		int event = index - num_gpes;
+		if (!strcmp(buf, "disable\n") &&
+		    (status & ACPI_EVENT_FLAG_ENABLE_SET))
+			result = acpi_disable_event(event, ACPI_NOT_ISR);
+		else if (!strcmp(buf, "enable\n") &&
+			 !(status & ACPI_EVENT_FLAG_ENABLE_SET))
+			result = acpi_enable_event(event, ACPI_NOT_ISR);
+		else if (!strcmp(buf, "clear\n") &&
+			 (status & ACPI_EVENT_FLAG_STATUS_SET))
+			result = acpi_clear_event(event);
+		else if (!kstrtoul(buf, 0, &tmp))
+			all_counters[index].count = tmp;
+		else
+			result = -EINVAL;
+	} else
+		all_counters[index].count = strtoul(buf, NULL, 0);
+
+	if (ACPI_FAILURE(result))
+		result = -EINVAL;
+end:
+	return result ? result : size;
+}
+
+/*
+ * A Quirk Mechanism for GPE Flooding Prevention:
+ *
+ * Quirks may be needed to prevent GPE flooding on a specific GPE. The
+ * flooding typically cannot be detected and automatically prevented by
+ * ACPI_GPE_DISPATCH_NONE check because there is a _Lxx/_Exx prepared in
+ * the AML tables. This normally indicates a feature gap in Linux, thus
+ * instead of providing endless quirk tables, we provide a boot parameter
+ * for those who want this quirk. For example, if the users want to prevent
+ * the GPE flooding for GPE 00, they need to specify the following boot
+ * parameter:
+ *   acpi_mask_gpe=0x00
+ * Note, the parameter can be a list (see bitmap_parselist() for the details).
+ * The masking status can be modified by the following runtime controlling
+ * interface:
+ *   echo unmask > /sys/firmware/acpi/interrupts/gpe00
+ */
+#define ACPI_MASKABLE_GPE_MAX	0x100
+static DECLARE_BITMAP(acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX) __initdata;
+
+static int __init acpi_gpe_set_masked_gpes(char *val)
+{
+	int ret;
+	u8 gpe;
+
+	ret = kstrtou8(val, 0, &gpe);
+	if (ret) {
+		ret = bitmap_parselist(val, acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX);
+		if (ret)
+			return ret;
+	} else
+		set_bit(gpe, acpi_masked_gpes_map);
+
+	return 1;
+}
+__setup("acpi_mask_gpe=", acpi_gpe_set_masked_gpes);
+
+void __init acpi_gpe_apply_masked_gpes(void)
+{
+	acpi_handle handle;
+	acpi_status status;
+	u16 gpe;
+
+	for_each_set_bit(gpe, acpi_masked_gpes_map, ACPI_MASKABLE_GPE_MAX) {
+		status = acpi_get_gpe_device(gpe, &handle);
+		if (ACPI_SUCCESS(status)) {
+			pr_info("Masking GPE 0x%x.\n", gpe);
+			(void)acpi_mask_gpe(handle, gpe, TRUE);
+		}
+	}
+}
+
+void acpi_irq_stats_init(void)
+{
+	acpi_status status;
+	int i;
+
+	if (all_counters)
+		return;
+
+	num_gpes = acpi_current_gpe_count;
+	num_counters = num_gpes + ACPI_NUM_FIXED_EVENTS + NUM_COUNTERS_EXTRA;
+
+	all_attrs = kzalloc_objs(*all_attrs, num_counters + 1);
+	if (all_attrs == NULL)
+		return;
+
+	all_counters = kzalloc_objs(*all_counters, num_counters);
+	if (all_counters == NULL)
+		goto fail;
+
+	status = acpi_install_global_event_handler(acpi_global_event_handler, NULL);
+	if (ACPI_FAILURE(status))
+		goto fail;
+
+	counter_attrs = kzalloc_objs(*counter_attrs, num_counters);
+	if (counter_attrs == NULL)
+		goto fail;
+
+	for (i = 0; i < num_counters; ++i) {
+		char buffer[12];
+		char *name;
+
+		if (i < num_gpes)
+			sprintf(buffer, "gpe%02X", i);
+		else if (i == num_gpes + ACPI_EVENT_PMTIMER)
+			sprintf(buffer, "ff_pmtimer");
+		else if (i == num_gpes + ACPI_EVENT_GLOBAL)
+			sprintf(buffer, "ff_gbl_lock");
+		else if (i == num_gpes + ACPI_EVENT_POWER_BUTTON)
+			sprintf(buffer, "ff_pwr_btn");
+		else if (i == num_gpes + ACPI_EVENT_SLEEP_BUTTON)
+			sprintf(buffer, "ff_slp_btn");
+		else if (i == num_gpes + ACPI_EVENT_RTC)
+			sprintf(buffer, "ff_rt_clk");
+		else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE)
+			sprintf(buffer, "gpe_all");
+		else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI)
+			sprintf(buffer, "sci");
+		else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI_NOT)
+			sprintf(buffer, "sci_not");
+		else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR)
+			sprintf(buffer, "error");
+		else
+			sprintf(buffer, "bug%02X", i);
+
+		name = kstrdup(buffer, GFP_KERNEL);
+		if (name == NULL)
+			goto fail;
+
+		sysfs_attr_init(&counter_attrs[i].attr);
+		counter_attrs[i].attr.name = name;
+		counter_attrs[i].attr.mode = 0644;
+		counter_attrs[i].show = counter_show;
+		counter_attrs[i].store = counter_set;
+
+		all_attrs[i] = &counter_attrs[i].attr;
+	}
+
+	interrupt_stats_attr_group.attrs = all_attrs;
+	if (!sysfs_create_group(acpi_kobj, &interrupt_stats_attr_group))
+		return;
+
+fail:
+	delete_gpe_attr_array();
+}
+
+static void __exit interrupt_stats_exit(void)
+{
+	sysfs_remove_group(acpi_kobj, &interrupt_stats_attr_group);
+
+	delete_gpe_attr_array();
+}
+
+static ssize_t pm_profile_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%d\n", acpi_gbl_FADT.preferred_profile);
+}
+
+static const struct kobj_attribute pm_profile_attr = __ATTR_RO(pm_profile);
+
+static ssize_t enabled_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	struct acpi_hotplug_profile *hotplug = to_acpi_hotplug_profile(kobj);
+
+	return sysfs_emit(buf, "%d\n", hotplug->enabled);
+}
+
+static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr,
+			     const char *buf, size_t size)
+{
+	struct acpi_hotplug_profile *hotplug = to_acpi_hotplug_profile(kobj);
+	unsigned int val;
+
+	if (kstrtouint(buf, 10, &val) || val > 1)
+		return -EINVAL;
+
+	acpi_scan_hotplug_enabled(hotplug, val);
+	return size;
+}
+
+static struct kobj_attribute hotplug_enabled_attr = __ATTR_RW(enabled);
+
+static struct attribute *hotplug_profile_attrs[] = {
+	&hotplug_enabled_attr.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(hotplug_profile);
+
+static const struct kobj_type acpi_hotplug_profile_ktype = {
+	.sysfs_ops = &kobj_sysfs_ops,
+	.default_groups = hotplug_profile_groups,
+};
+
+void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug,
+				    const char *name)
+{
+	int error;
+
+	if (!hotplug_kobj)
+		goto err_out;
+
+	error = kobject_init_and_add(&hotplug->kobj,
+		&acpi_hotplug_profile_ktype, hotplug_kobj, "%s", name);
+	if (error) {
+		kobject_put(&hotplug->kobj);
+		goto err_out;
+	}
+
+	kobject_uevent(&hotplug->kobj, KOBJ_ADD);
+	return;
+
+ err_out:
+	pr_err("Unable to add hotplug profile '%s'\n", name);
+}
+
+static ssize_t force_remove_show(struct kobject *kobj,
+				 struct kobj_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%d\n", 0);
+}
+
+static ssize_t force_remove_store(struct kobject *kobj,
+				  struct kobj_attribute *attr,
+				  const char *buf, size_t size)
+{
+	bool val;
+	int ret;
+
+	ret = kstrtobool(buf, &val);
+	if (ret < 0)
+		return ret;
+
+	if (val) {
+		pr_err("Enabling force_remove is not supported anymore. Please report to linux-acpi@vger.kernel.org if you depend on this functionality\n");
+		return -EINVAL;
+	}
+	return size;
+}
+
+static const struct kobj_attribute force_remove_attr = __ATTR_RW(force_remove);
+
+int __init acpi_sysfs_init(void)
+{
+	int result;
+
+	result = acpi_tables_sysfs_init();
+	if (result)
+		return result;
+
+	hotplug_kobj = kobject_create_and_add("hotplug", acpi_kobj);
+	if (!hotplug_kobj)
+		return -ENOMEM;
+
+	result = sysfs_create_file(hotplug_kobj, &force_remove_attr.attr);
+	if (result)
+		return result;
+
+	result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr);
+	return result;
+}