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, 308 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/exdebug.c b/drivers/acpi/acpica/exdebug.c
new file mode 100644
index 000000000..a592bcc5d
--- /dev/null
+++ b/drivers/acpi/acpica/exdebug.c
@@ -0,0 +1,308 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: exdebug - Support for stores to the AML Debug Object
+ *
+ * Copyright (C) 2000 - 2026, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acinterp.h"
+
+#define _COMPONENT          ACPI_EXECUTER
+ACPI_MODULE_NAME("exdebug")
+
+#ifndef ACPI_NO_ERROR_MESSAGES
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_do_debug_object
+ *
+ * PARAMETERS:  source_desc         - Object to be output to "Debug Object"
+ *              level               - Indentation level (used for packages)
+ *              index               - Current package element, zero if not pkg
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Handles stores to the AML Debug Object. For example:
+ *              Store(INT1, Debug)
+ *
+ * This function is not compiled if ACPI_NO_ERROR_MESSAGES is set.
+ *
+ * This function is only enabled if acpi_gbl_enable_aml_debug_object is set, or
+ * if ACPI_LV_DEBUG_OBJECT is set in the acpi_dbg_level. Thus, in the normal
+ * operational case, stores to the debug object are ignored but can be easily
+ * enabled if necessary.
+ *
+ ******************************************************************************/
+void
+acpi_ex_do_debug_object(union acpi_operand_object *source_desc,
+			u32 level, u32 index)
+{
+	u32 i;
+	u32 timer;
+	union acpi_operand_object *object_desc;
+	u32 value;
+
+	ACPI_FUNCTION_TRACE_PTR(ex_do_debug_object, source_desc);
+
+	/* Output must be enabled via the debug_object global or the dbg_level */
+
+	if (!acpi_gbl_enable_aml_debug_object &&
+	    !(acpi_dbg_level & ACPI_LV_DEBUG_OBJECT)) {
+		return_VOID;
+	}
+
+	/* Newline -- don't emit the line header */
+
+	if (source_desc &&
+	    (ACPI_GET_DESCRIPTOR_TYPE(source_desc) == ACPI_DESC_TYPE_OPERAND) &&
+	    (source_desc->common.type == ACPI_TYPE_STRING)) {
+		if ((source_desc->string.length == 1) &&
+		    (*source_desc->string.pointer == '\n')) {
+			acpi_os_printf("\n");
+			return_VOID;
+		}
+	}
+
+	/*
+	 * Print line header as long as we are not in the middle of an
+	 * object display
+	 */
+	if (!((level > 0) && index == 0)) {
+		if (acpi_gbl_display_debug_timer) {
+			/*
+			 * We will emit the current timer value (in microseconds) with each
+			 * debug output. Only need the lower 26 bits. This allows for 67
+			 * million microseconds or 67 seconds before rollover.
+			 *
+			 * Convert 100 nanosecond units to microseconds
+			 */
+			timer = ((u32)acpi_os_get_timer() / 10);
+			timer &= 0x03FFFFFF;
+
+			acpi_os_printf("ACPI Debug: T=0x%8.8X %*s", timer,
+				       level, " ");
+		} else {
+			acpi_os_printf("ACPI Debug: %*s", level, " ");
+		}
+	}
+
+	/* Display the index for package output only */
+
+	if (index > 0) {
+		acpi_os_printf("(%.2u) ", index - 1);
+	}
+
+	if (!source_desc) {
+		acpi_os_printf("[Null Object]\n");
+		return_VOID;
+	}
+
+	if (ACPI_GET_DESCRIPTOR_TYPE(source_desc) == ACPI_DESC_TYPE_OPERAND) {
+
+		/* No object type prefix needed for integers and strings */
+
+		if ((source_desc->common.type != ACPI_TYPE_INTEGER) &&
+		    (source_desc->common.type != ACPI_TYPE_STRING)) {
+			acpi_os_printf("%s ",
+				       acpi_ut_get_object_type_name
+				       (source_desc));
+		}
+
+		if (!acpi_ut_valid_internal_object(source_desc)) {
+			acpi_os_printf("%p, Invalid Internal Object!\n",
+				       source_desc);
+			return_VOID;
+		}
+	} else if (ACPI_GET_DESCRIPTOR_TYPE(source_desc) ==
+		   ACPI_DESC_TYPE_NAMED) {
+		acpi_os_printf("%s (Node %p)\n",
+			       acpi_ut_get_type_name(((struct
+						       acpi_namespace_node *)
+						      source_desc)->type),
+			       source_desc);
+		return_VOID;
+	} else {
+		return_VOID;
+	}
+
+	/* source_desc is of type ACPI_DESC_TYPE_OPERAND */
+
+	switch (source_desc->common.type) {
+	case ACPI_TYPE_INTEGER:
+
+		/* Output correct integer width */
+
+		if (acpi_gbl_integer_byte_width == 4) {
+			acpi_os_printf("0x%8.8X\n",
+				       (u32)source_desc->integer.value);
+		} else {
+			acpi_os_printf("0x%8.8X%8.8X\n",
+				       ACPI_FORMAT_UINT64(source_desc->integer.
+							  value));
+		}
+		break;
+
+	case ACPI_TYPE_BUFFER:
+
+		acpi_os_printf("[0x%.2X]\n", (u32)source_desc->buffer.length);
+		acpi_ut_dump_buffer(source_desc->buffer.pointer,
+				    (source_desc->buffer.length < 256) ?
+				    source_desc->buffer.length : 256,
+				    DB_BYTE_DISPLAY, 0);
+		break;
+
+	case ACPI_TYPE_STRING:
+
+		acpi_os_printf("\"%s\"\n", source_desc->string.pointer);
+		break;
+
+	case ACPI_TYPE_PACKAGE:
+
+		acpi_os_printf("(Contains 0x%.2X Elements):\n",
+			       source_desc->package.count);
+
+		/* Output the entire contents of the package */
+
+		for (i = 0; i < source_desc->package.count; i++) {
+			acpi_ex_do_debug_object(source_desc->package.
+						elements[i], level + 4, i + 1);
+		}
+		break;
+
+	case ACPI_TYPE_LOCAL_REFERENCE:
+
+		acpi_os_printf("[%s] ",
+			       acpi_ut_get_reference_name(source_desc));
+
+		/* Decode the reference */
+
+		switch (source_desc->reference.class) {
+		case ACPI_REFCLASS_INDEX:
+
+			acpi_os_printf("0x%X\n", source_desc->reference.value);
+			break;
+
+		case ACPI_REFCLASS_TABLE:
+
+			/* Case for ddb_handle */
+
+			acpi_os_printf("Table Index 0x%X\n",
+				       source_desc->reference.value);
+			return_VOID;
+
+		default:
+
+			break;
+		}
+
+		acpi_os_printf(" ");
+
+		/* Check for valid node first, then valid object */
+
+		if (source_desc->reference.node) {
+			if (ACPI_GET_DESCRIPTOR_TYPE
+			    (source_desc->reference.node) !=
+			    ACPI_DESC_TYPE_NAMED) {
+				acpi_os_printf
+				    (" %p - Not a valid namespace node\n",
+				     source_desc->reference.node);
+			} else {
+				acpi_os_printf("Node %p [%4.4s] ",
+					       source_desc->reference.node,
+					       (source_desc->reference.node)->
+					       name.ascii);
+
+				switch ((source_desc->reference.node)->type) {
+
+					/* These types have no attached object */
+
+				case ACPI_TYPE_DEVICE:
+					acpi_os_printf("Device\n");
+					break;
+
+				case ACPI_TYPE_THERMAL:
+					acpi_os_printf("Thermal Zone\n");
+					break;
+
+				default:
+
+					acpi_ex_do_debug_object((source_desc->
+								 reference.
+								 node)->object,
+								level + 4, 0);
+					break;
+				}
+			}
+		} else if (source_desc->reference.object) {
+			if (ACPI_GET_DESCRIPTOR_TYPE
+			    (source_desc->reference.object) ==
+			    ACPI_DESC_TYPE_NAMED) {
+
+				/* Reference object is a namespace node */
+
+				acpi_ex_do_debug_object(ACPI_CAST_PTR
+							(union
+							 acpi_operand_object,
+							 source_desc->reference.
+							 object), level + 4, 0);
+			} else {
+				object_desc = source_desc->reference.object;
+				value = source_desc->reference.value;
+
+				switch (object_desc->common.type) {
+				case ACPI_TYPE_BUFFER:
+
+					acpi_os_printf("Buffer[%u] = 0x%2.2X\n",
+						       value,
+						       *source_desc->reference.
+						       index_pointer);
+					break;
+
+				case ACPI_TYPE_STRING:
+
+					acpi_os_printf
+					    ("String[%u] = \"%c\" (0x%2.2X)\n",
+					     value,
+					     *source_desc->reference.
+					     index_pointer,
+					     *source_desc->reference.
+					     index_pointer);
+					break;
+
+				case ACPI_TYPE_PACKAGE:
+
+					acpi_os_printf("Package[%u] = ", value);
+					if (!(*source_desc->reference.where)) {
+						acpi_os_printf
+						    ("[Uninitialized Package Element]\n");
+					} else {
+						acpi_ex_do_debug_object
+						    (*source_desc->reference.
+						     where, level + 4, 0);
+					}
+					break;
+
+				default:
+
+					acpi_os_printf
+					    ("Unknown Reference object type %X\n",
+					     object_desc->common.type);
+					break;
+				}
+			}
+		}
+		break;
+
+	default:
+
+		acpi_os_printf("(Descriptor %p)\n", source_desc);
+		break;
+	}
+
+	ACPI_DEBUG_PRINT_RAW((ACPI_DB_EXEC, "\n"));
+	return_VOID;
+}
+#endif