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, 545 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/evhandler.c b/drivers/acpi/acpica/evhandler.c
new file mode 100644
index 000000000..d9a3b1ca5
--- /dev/null
+++ b/drivers/acpi/acpica/evhandler.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: evhandler - Support for Address Space handlers
+ *
+ * Copyright (C) 2000 - 2026, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acevents.h"
+#include "acnamesp.h"
+#include "acinterp.h"
+
+#define _COMPONENT          ACPI_EVENTS
+ACPI_MODULE_NAME("evhandler")
+
+/* Local prototypes */
+static acpi_status
+acpi_ev_install_handler(acpi_handle obj_handle,
+			u32 level, void *context, void **return_value);
+
+/* These are the address spaces that will get default handlers */
+
+u8 acpi_gbl_default_address_spaces[ACPI_NUM_DEFAULT_SPACES] = {
+	ACPI_ADR_SPACE_SYSTEM_MEMORY,
+	ACPI_ADR_SPACE_SYSTEM_IO,
+	ACPI_ADR_SPACE_PCI_CONFIG,
+	ACPI_ADR_SPACE_DATA_TABLE
+};
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_install_region_handlers
+ *
+ * PARAMETERS:  None
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Installs the core subsystem default address space handlers.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ev_install_region_handlers(void)
+{
+	acpi_status status;
+	u32 i;
+
+	ACPI_FUNCTION_TRACE(ev_install_region_handlers);
+
+	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
+
+	/*
+	 * All address spaces (PCI Config, EC, SMBus) are scope dependent and
+	 * registration must occur for a specific device.
+	 *
+	 * In the case of the system memory and IO address spaces there is
+	 * currently no device associated with the address space. For these we
+	 * use the root.
+	 *
+	 * We install the default PCI config space handler at the root so that
+	 * this space is immediately available even though the we have not
+	 * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
+	 * specification which states that the PCI config space must be always
+	 * available -- even though we are nowhere near ready to find the PCI root
+	 * buses at this point.
+	 *
+	 * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
+	 * has already been installed (via acpi_install_address_space_handler).
+	 * Similar for AE_SAME_HANDLER.
+	 */
+	for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
+		status = acpi_ev_install_space_handler(acpi_gbl_root_node,
+						       acpi_gbl_default_address_spaces
+						       [i],
+						       ACPI_DEFAULT_HANDLER,
+						       NULL, NULL);
+		switch (status) {
+		case AE_OK:
+		case AE_SAME_HANDLER:
+		case AE_ALREADY_EXISTS:
+
+			/* These exceptions are all OK */
+
+			status = AE_OK;
+			break;
+
+		default:
+
+			goto unlock_and_exit;
+		}
+	}
+
+unlock_and_exit:
+	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+	return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_has_default_handler
+ *
+ * PARAMETERS:  node                - Namespace node for the device
+ *              space_id            - The address space ID
+ *
+ * RETURN:      TRUE if default handler is installed, FALSE otherwise
+ *
+ * DESCRIPTION: Check if the default handler is installed for the requested
+ *              space ID.
+ *
+ ******************************************************************************/
+
+u8
+acpi_ev_has_default_handler(struct acpi_namespace_node *node,
+			    acpi_adr_space_type space_id)
+{
+	union acpi_operand_object *obj_desc;
+	union acpi_operand_object *handler_obj;
+
+	/* Must have an existing internal object */
+
+	obj_desc = acpi_ns_get_attached_object(node);
+	if (obj_desc) {
+		handler_obj = obj_desc->common_notify.handler;
+
+		/* Walk the linked list of handlers for this object */
+
+		while (handler_obj) {
+
+			/* Validate handler object type before accessing fields */
+
+			if (handler_obj->common.type !=
+			    ACPI_TYPE_LOCAL_ADDRESS_HANDLER) {
+				break;
+			}
+
+			if (handler_obj->address_space.space_id == space_id) {
+				if (handler_obj->address_space.handler_flags &
+				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
+					return (TRUE);
+				}
+			}
+
+			handler_obj = handler_obj->address_space.next;
+		}
+	}
+
+	return (FALSE);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_install_handler
+ *
+ * PARAMETERS:  walk_namespace callback
+ *
+ * DESCRIPTION: This routine installs an address handler into objects that are
+ *              of type Region or Device.
+ *
+ *              If the Object is a Device, and the device has a handler of
+ *              the same type then the search is terminated in that branch.
+ *
+ *              This is because the existing handler is closer in proximity
+ *              to any more regions than the one we are trying to install.
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ev_install_handler(acpi_handle obj_handle,
+			u32 level, void *context, void **return_value)
+{
+	union acpi_operand_object *handler_obj;
+	union acpi_operand_object *next_handler_obj;
+	union acpi_operand_object *obj_desc;
+	struct acpi_namespace_node *node;
+	acpi_status status;
+
+	ACPI_FUNCTION_NAME(ev_install_handler);
+
+	handler_obj = (union acpi_operand_object *)context;
+
+	/* Parameter validation */
+
+	if (!handler_obj) {
+		return (AE_OK);
+	}
+
+	/* Convert and validate the device handle */
+
+	node = acpi_ns_validate_handle(obj_handle);
+	if (!node) {
+		return (AE_BAD_PARAMETER);
+	}
+
+	/*
+	 * We only care about regions and objects that are allowed to have
+	 * address space handlers
+	 */
+	if ((node->type != ACPI_TYPE_DEVICE) &&
+	    (node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
+		return (AE_OK);
+	}
+
+	/* Check for an existing internal object */
+
+	obj_desc = acpi_ns_get_attached_object(node);
+	if (!obj_desc) {
+
+		/* No object, just exit */
+
+		return (AE_OK);
+	}
+
+	/* Devices are handled different than regions */
+
+	if (obj_desc->common.type == ACPI_TYPE_DEVICE) {
+
+		/* Check if this Device already has a handler for this address space */
+
+		next_handler_obj =
+		    acpi_ev_find_region_handler(handler_obj->address_space.
+						space_id,
+						obj_desc->common_notify.
+						handler);
+		if (next_handler_obj) {
+
+			/* Found a handler, is it for the same address space? */
+
+			ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+					  "Found handler for region [%s] in device %p(%p) handler %p\n",
+					  acpi_ut_get_region_name(handler_obj->
+								  address_space.
+								  space_id),
+					  obj_desc, next_handler_obj,
+					  handler_obj));
+
+			/*
+			 * Since the object we found it on was a device, then it means
+			 * that someone has already installed a handler for the branch
+			 * of the namespace from this device on. Just bail out telling
+			 * the walk routine to not traverse this branch. This preserves
+			 * the scoping rule for handlers.
+			 */
+			return (AE_CTRL_DEPTH);
+		}
+
+		/*
+		 * As long as the device didn't have a handler for this space we
+		 * don't care about it. We just ignore it and proceed.
+		 */
+		return (AE_OK);
+	}
+
+	/* Object is a Region */
+
+	if (obj_desc->region.space_id != handler_obj->address_space.space_id) {
+
+		/* This region is for a different address space, just ignore it */
+
+		return (AE_OK);
+	}
+
+	/*
+	 * Now we have a region and it is for the handler's address space type.
+	 *
+	 * First disconnect region for any previous handler (if any)
+	 */
+	acpi_ev_detach_region(obj_desc, FALSE);
+
+	/* Connect the region to the new handler */
+
+	status = acpi_ev_attach_region(handler_obj, obj_desc, FALSE);
+	return (status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_find_region_handler
+ *
+ * PARAMETERS:  space_id        - The address space ID
+ *              handler_obj     - Head of the handler object list
+ *
+ * RETURN:      Matching handler object. NULL if space ID not matched
+ *
+ * DESCRIPTION: Search a handler object list for a match on the address
+ *              space ID.
+ *
+ ******************************************************************************/
+
+union acpi_operand_object *acpi_ev_find_region_handler(acpi_adr_space_type
+						       space_id,
+						       union acpi_operand_object
+						       *handler_obj)
+{
+
+	/* Walk the handler list for this device */
+
+	while (handler_obj) {
+		if (handler_obj->common.type != ACPI_TYPE_LOCAL_ADDRESS_HANDLER) {
+			break;
+		}
+
+		/* Same space_id indicates a handler is installed */
+
+		if (handler_obj->address_space.space_id == space_id) {
+			return (handler_obj);
+		}
+
+		/* Next handler object */
+
+		handler_obj = handler_obj->address_space.next;
+	}
+
+	return (NULL);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_install_space_handler
+ *
+ * PARAMETERS:  node            - Namespace node for the device
+ *              space_id        - The address space ID
+ *              handler         - Address of the handler
+ *              setup           - Address of the setup function
+ *              context         - Value passed to the handler on each access
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Install a handler for all op_regions of a given space_id.
+ *              Assumes namespace is locked
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_install_space_handler(struct acpi_namespace_node *node,
+			      acpi_adr_space_type space_id,
+			      acpi_adr_space_handler handler,
+			      acpi_adr_space_setup setup, void *context)
+{
+	union acpi_operand_object *obj_desc;
+	union acpi_operand_object *handler_obj;
+	acpi_status status = AE_OK;
+	acpi_object_type type;
+	u8 flags = 0;
+
+	ACPI_FUNCTION_TRACE(ev_install_space_handler);
+
+	/*
+	 * This registration is valid for only the types below and the root.
+	 * The root node is where the default handlers get installed.
+	 */
+	if ((node->type != ACPI_TYPE_DEVICE) &&
+	    (node->type != ACPI_TYPE_PROCESSOR) &&
+	    (node->type != ACPI_TYPE_THERMAL) && (node != acpi_gbl_root_node)) {
+		status = AE_BAD_PARAMETER;
+		goto unlock_and_exit;
+	}
+
+	if (handler == ACPI_DEFAULT_HANDLER) {
+		flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
+
+		switch (space_id) {
+		case ACPI_ADR_SPACE_SYSTEM_MEMORY:
+
+			handler = acpi_ex_system_memory_space_handler;
+			setup = acpi_ev_system_memory_region_setup;
+			break;
+
+		case ACPI_ADR_SPACE_SYSTEM_IO:
+
+			handler = acpi_ex_system_io_space_handler;
+			setup = acpi_ev_io_space_region_setup;
+			break;
+#ifdef ACPI_PCI_CONFIGURED
+		case ACPI_ADR_SPACE_PCI_CONFIG:
+
+			handler = acpi_ex_pci_config_space_handler;
+			setup = acpi_ev_pci_config_region_setup;
+			break;
+#endif
+		case ACPI_ADR_SPACE_CMOS:
+
+			handler = acpi_ex_cmos_space_handler;
+			setup = acpi_ev_cmos_region_setup;
+			break;
+#ifdef ACPI_PCI_CONFIGURED
+		case ACPI_ADR_SPACE_PCI_BAR_TARGET:
+
+			handler = acpi_ex_pci_bar_space_handler;
+			setup = acpi_ev_pci_bar_region_setup;
+			break;
+#endif
+		case ACPI_ADR_SPACE_DATA_TABLE:
+
+			handler = acpi_ex_data_table_space_handler;
+			setup = acpi_ev_data_table_region_setup;
+			break;
+
+		default:
+
+			status = AE_BAD_PARAMETER;
+			goto unlock_and_exit;
+		}
+	}
+
+	/* If the caller hasn't specified a setup routine, use the default */
+
+	if (!setup) {
+		setup = acpi_ev_default_region_setup;
+	}
+
+	/* Check for an existing internal object */
+
+	obj_desc = acpi_ns_get_attached_object(node);
+	if (obj_desc) {
+		/*
+		 * The attached device object already exists. Now make sure
+		 * the handler is not already installed.
+		 */
+		handler_obj = acpi_ev_find_region_handler(space_id,
+							  obj_desc->
+							  common_notify.
+							  handler);
+
+		if (handler_obj) {
+			if (handler_obj->address_space.handler == handler) {
+				/*
+				 * It is (relatively) OK to attempt to install the SAME
+				 * handler twice. This can easily happen with the
+				 * PCI_Config space.
+				 */
+				status = AE_SAME_HANDLER;
+				goto unlock_and_exit;
+			} else {
+				/* A handler is already installed */
+
+				status = AE_ALREADY_EXISTS;
+			}
+
+			goto unlock_and_exit;
+		}
+	} else {
+		ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+				  "Creating object on Device %p while installing handler\n",
+				  node));
+
+		/* obj_desc does not exist, create one */
+
+		if (node->type == ACPI_TYPE_ANY) {
+			type = ACPI_TYPE_DEVICE;
+		} else {
+			type = node->type;
+		}
+
+		obj_desc = acpi_ut_create_internal_object(type);
+		if (!obj_desc) {
+			status = AE_NO_MEMORY;
+			goto unlock_and_exit;
+		}
+
+		/* Init new descriptor */
+
+		obj_desc->common.type = (u8)type;
+
+		/* Attach the new object to the Node */
+
+		status = acpi_ns_attach_object(node, obj_desc, type);
+
+		/* Remove local reference to the object */
+
+		acpi_ut_remove_reference(obj_desc);
+
+		if (ACPI_FAILURE(status)) {
+			goto unlock_and_exit;
+		}
+	}
+
+	ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+			  "Installing address handler for region %s(%X) "
+			  "on Device %4.4s %p(%p)\n",
+			  acpi_ut_get_region_name(space_id), space_id,
+			  acpi_ut_get_node_name(node), node, obj_desc));
+
+	/*
+	 * Install the handler
+	 *
+	 * At this point there is no existing handler. Just allocate the object
+	 * for the handler and link it into the list.
+	 */
+	handler_obj =
+	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
+	if (!handler_obj) {
+		status = AE_NO_MEMORY;
+		goto unlock_and_exit;
+	}
+
+	/* Init handler obj */
+
+	status =
+	    acpi_os_create_mutex(&handler_obj->address_space.context_mutex);
+	if (ACPI_FAILURE(status)) {
+		acpi_ut_remove_reference(handler_obj);
+		goto unlock_and_exit;
+	}
+
+	handler_obj->address_space.space_id = (u8)space_id;
+	handler_obj->address_space.handler_flags = flags;
+	handler_obj->address_space.region_list = NULL;
+	handler_obj->address_space.node = node;
+	handler_obj->address_space.handler = handler;
+	handler_obj->address_space.context = context;
+	handler_obj->address_space.setup = setup;
+
+	/* Install at head of Device.address_space list */
+
+	handler_obj->address_space.next = obj_desc->common_notify.handler;
+
+	/*
+	 * The Device object is the first reference on the handler_obj.
+	 * Each region that uses the handler adds a reference.
+	 */
+	obj_desc->common_notify.handler = handler_obj;
+
+	/*
+	 * Walk the namespace finding all of the regions this handler will
+	 * manage.
+	 *
+	 * Start at the device and search the branch toward the leaf nodes
+	 * until either the leaf is encountered or a device is detected that
+	 * has an address handler of the same type.
+	 *
+	 * In either case, back up and search down the remainder of the branch
+	 */
+	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node,
+					ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
+					acpi_ev_install_handler, NULL,
+					handler_obj, NULL);
+
+unlock_and_exit:
+	return_ACPI_STATUS(status);
+}