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, 424 insertions, 0 deletions

diff --git a/drivers/acpi/prmt.c b/drivers/acpi/prmt.c
new file mode 100644
index 000000000..7f5851371
--- /dev/null
+++ b/drivers/acpi/prmt.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Author: Erik Kaneda <erik.kaneda@intel.com>
+ * Copyright 2020 Intel Corporation
+ *
+ * prmt.c
+ *
+ * Each PRM service is an executable that is run in a restricted environment
+ * that is invoked by writing to the PlatformRtMechanism OperationRegion from
+ * AML bytecode.
+ *
+ * init_prmt initializes the Platform Runtime Mechanism (PRM) services by
+ * processing data in the PRMT as well as registering an ACPI OperationRegion
+ * handler for the PlatformRtMechanism subtype.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/efi.h>
+#include <linux/acpi.h>
+#include <linux/prmt.h>
+#include <asm/efi.h>
+
+#pragma pack(1)
+struct prm_mmio_addr_range {
+	u64 phys_addr;
+	u64 virt_addr;
+	u32 length;
+};
+
+struct prm_mmio_info {
+	u64 mmio_count;
+	struct prm_mmio_addr_range addr_ranges[];
+};
+
+struct prm_buffer {
+	u8 prm_status;
+	u64 efi_status;
+	u8 prm_cmd;
+	guid_t handler_guid;
+};
+
+struct prm_context_buffer {
+	char signature[ACPI_NAMESEG_SIZE];
+	u16 revision;
+	u16 reserved;
+	guid_t identifier;
+	u64 static_data_buffer;
+	struct prm_mmio_info *mmio_ranges;
+};
+#pragma pack()
+
+static LIST_HEAD(prm_module_list);
+
+struct prm_handler_info {
+	efi_guid_t guid;
+	efi_status_t (__efiapi *handler_addr)(u64, void *);
+	u64 static_data_buffer_addr;
+	u64 acpi_param_buffer_addr;
+
+	struct list_head handler_list;
+};
+
+struct prm_module_info {
+	guid_t guid;
+	u16 major_rev;
+	u16 minor_rev;
+	u16 handler_count;
+	struct prm_mmio_info *mmio_info;
+	bool updatable;
+
+	struct list_head module_list;
+	struct prm_handler_info handlers[] __counted_by(handler_count);
+};
+
+static u64 efi_pa_va_lookup(efi_guid_t *guid, u64 pa)
+{
+	efi_memory_desc_t *md;
+	u64 pa_offset = pa & ~PAGE_MASK;
+	u64 page = pa & PAGE_MASK;
+
+	for_each_efi_memory_desc(md) {
+		if ((md->attribute & EFI_MEMORY_RUNTIME) &&
+		    (md->phys_addr < pa && pa < md->phys_addr + PAGE_SIZE * md->num_pages)) {
+			return pa_offset + md->virt_addr + page - md->phys_addr;
+		}
+	}
+
+	return 0;
+}
+
+#define get_first_handler(a) ((struct acpi_prmt_handler_info *) ((char *) (a) + a->handler_info_offset))
+#define get_next_handler(a) ((struct acpi_prmt_handler_info *) (sizeof(struct acpi_prmt_handler_info) + (char *) a))
+
+static int __init
+acpi_parse_prmt(union acpi_subtable_headers *header, const unsigned long end)
+{
+	struct acpi_prmt_module_info *module_info;
+	struct acpi_prmt_handler_info *handler_info;
+	struct prm_handler_info *th;
+	struct prm_module_info *tm;
+	u64 *mmio_count;
+	u64 cur_handler = 0;
+	u32 module_info_size = 0;
+	u64 mmio_range_size = 0;
+	void *temp_mmio;
+
+	module_info = (struct acpi_prmt_module_info *) header;
+	module_info_size = struct_size(tm, handlers, module_info->handler_info_count);
+	tm = kmalloc(module_info_size, GFP_KERNEL);
+	if (!tm)
+		goto parse_prmt_out1;
+
+	guid_copy(&tm->guid, (guid_t *) module_info->module_guid);
+	tm->major_rev = module_info->major_rev;
+	tm->minor_rev = module_info->minor_rev;
+	tm->handler_count = module_info->handler_info_count;
+	tm->updatable = true;
+
+	if (module_info->mmio_list_pointer) {
+		/*
+		 * Each module is associated with a list of addr
+		 * ranges that it can use during the service
+		 */
+		mmio_count = (u64 *) memremap(module_info->mmio_list_pointer, 8, MEMREMAP_WB);
+		if (!mmio_count)
+			goto parse_prmt_out2;
+
+		mmio_range_size = struct_size(tm->mmio_info, addr_ranges, *mmio_count);
+		tm->mmio_info = kmalloc(mmio_range_size, GFP_KERNEL);
+		if (!tm->mmio_info)
+			goto parse_prmt_out3;
+
+		temp_mmio = memremap(module_info->mmio_list_pointer, mmio_range_size, MEMREMAP_WB);
+		if (!temp_mmio)
+			goto parse_prmt_out4;
+		memmove(tm->mmio_info, temp_mmio, mmio_range_size);
+	} else {
+		tm->mmio_info = kmalloc_obj(*tm->mmio_info);
+		if (!tm->mmio_info)
+			goto parse_prmt_out2;
+
+		tm->mmio_info->mmio_count = 0;
+	}
+
+	INIT_LIST_HEAD(&tm->module_list);
+	list_add(&tm->module_list, &prm_module_list);
+
+	handler_info = get_first_handler(module_info);
+	do {
+		th = &tm->handlers[cur_handler];
+
+		guid_copy(&th->guid, (guid_t *)handler_info->handler_guid);
+
+		/*
+		 * Print an error message if handler_address is NULL, the parse of VA also
+		 * can be skipped.
+		 */
+		if (unlikely(!handler_info->handler_address)) {
+			pr_info("Skipping handler with NULL address for GUID: %pUL",
+					(guid_t *)handler_info->handler_guid);
+			continue;
+		}
+
+		th->handler_addr =
+			(void *)efi_pa_va_lookup(&th->guid, handler_info->handler_address);
+		/*
+		 * Print a warning message and skip the parse of VA if handler_addr is zero
+		 * which is not expected to ever happen.
+		 */
+		if (unlikely(!th->handler_addr)) {
+			pr_warn("Failed to find VA of handler for GUID: %pUL, PA: 0x%llx",
+				&th->guid, handler_info->handler_address);
+			continue;
+		}
+
+		th->static_data_buffer_addr =
+			efi_pa_va_lookup(&th->guid, handler_info->static_data_buffer_address);
+		/*
+		 * According to the PRM specification, static_data_buffer_address can be zero,
+		 * so avoid printing a warning message in that case.  Otherwise, if the
+		 * return value of efi_pa_va_lookup() is zero, print the message.
+		 */
+		if (unlikely(!th->static_data_buffer_addr && handler_info->static_data_buffer_address))
+			pr_warn("Failed to find VA of static data buffer for GUID: %pUL, PA: 0x%llx",
+				&th->guid, handler_info->static_data_buffer_address);
+
+		th->acpi_param_buffer_addr =
+			efi_pa_va_lookup(&th->guid, handler_info->acpi_param_buffer_address);
+
+		/*
+		 * According to the PRM specification, acpi_param_buffer_address can be zero,
+		 * so avoid printing a warning message in that case.  Otherwise, if the
+		 * return value of efi_pa_va_lookup() is zero, print the message.
+		 */
+		if (unlikely(!th->acpi_param_buffer_addr && handler_info->acpi_param_buffer_address))
+			pr_warn("Failed to find VA of acpi param buffer for GUID: %pUL, PA: 0x%llx",
+				&th->guid, handler_info->acpi_param_buffer_address);
+
+	} while (++cur_handler < tm->handler_count && (handler_info = get_next_handler(handler_info)));
+
+	return 0;
+
+parse_prmt_out4:
+	kfree(tm->mmio_info);
+parse_prmt_out3:
+	memunmap(mmio_count);
+parse_prmt_out2:
+	kfree(tm);
+parse_prmt_out1:
+	return -ENOMEM;
+}
+
+#define GET_MODULE	0
+#define GET_HANDLER	1
+
+static void *find_guid_info(const guid_t *guid, u8 mode)
+{
+	struct prm_handler_info *cur_handler;
+	struct prm_module_info *cur_module;
+	int i = 0;
+
+	list_for_each_entry(cur_module, &prm_module_list, module_list) {
+		for (i = 0; i < cur_module->handler_count; ++i) {
+			cur_handler = &cur_module->handlers[i];
+			if (guid_equal(guid, &cur_handler->guid)) {
+				if (mode == GET_MODULE)
+					return (void *)cur_module;
+				else
+					return (void *)cur_handler;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+static struct prm_module_info *find_prm_module(const guid_t *guid)
+{
+	return (struct prm_module_info *)find_guid_info(guid, GET_MODULE);
+}
+
+static struct prm_handler_info *find_prm_handler(const guid_t *guid)
+{
+	return (struct prm_handler_info *) find_guid_info(guid, GET_HANDLER);
+}
+
+bool acpi_prm_handler_available(const guid_t *guid)
+{
+	return find_prm_handler(guid) && find_prm_module(guid);
+}
+EXPORT_SYMBOL_GPL(acpi_prm_handler_available);
+
+/* In-coming PRM commands */
+
+#define PRM_CMD_RUN_SERVICE		0
+#define PRM_CMD_START_TRANSACTION	1
+#define PRM_CMD_END_TRANSACTION		2
+
+/* statuses that can be passed back to ASL */
+
+#define PRM_HANDLER_SUCCESS 		0
+#define PRM_HANDLER_ERROR 		1
+#define INVALID_PRM_COMMAND 		2
+#define PRM_HANDLER_GUID_NOT_FOUND 	3
+#define UPDATE_LOCK_ALREADY_HELD 	4
+#define UPDATE_UNLOCK_WITHOUT_LOCK 	5
+
+int acpi_call_prm_handler(guid_t handler_guid, void *param_buffer)
+{
+	struct prm_handler_info *handler = find_prm_handler(&handler_guid);
+	struct prm_module_info *module = find_prm_module(&handler_guid);
+	struct prm_context_buffer context;
+	efi_status_t status;
+
+	if (!module || !handler)
+		return -ENODEV;
+
+	memset(&context, 0, sizeof(context));
+	ACPI_COPY_NAMESEG(context.signature, "PRMC");
+	context.identifier         = handler->guid;
+	context.static_data_buffer = handler->static_data_buffer_addr;
+	context.mmio_ranges        = module->mmio_info;
+
+	status = efi_call_acpi_prm_handler(handler->handler_addr,
+					   (u64)param_buffer,
+					   &context);
+
+	return efi_status_to_err(status);
+}
+EXPORT_SYMBOL_GPL(acpi_call_prm_handler);
+
+/*
+ * This is the PlatformRtMechanism opregion space handler.
+ * @function: indicates the read/write. In fact as the PlatformRtMechanism
+ * message is driven by command, only write is meaningful.
+ *
+ * @addr   : not used
+ * @bits   : not used.
+ * @value  : it is an in/out parameter. It points to the PRM message buffer.
+ * @handler_context: not used
+ */
+static acpi_status acpi_platformrt_space_handler(u32 function,
+						 acpi_physical_address addr,
+						 u32 bits, acpi_integer *value,
+						 void *handler_context,
+						 void *region_context)
+{
+	struct prm_buffer *buffer = ACPI_CAST_PTR(struct prm_buffer, value);
+	struct prm_handler_info *handler;
+	struct prm_module_info *module;
+	efi_status_t status;
+	struct prm_context_buffer context;
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
+		pr_err_ratelimited("PRM: EFI runtime services no longer available\n");
+		return AE_NO_HANDLER;
+	}
+
+	/*
+	 * The returned acpi_status will always be AE_OK. Error values will be
+	 * saved in the first byte of the PRM message buffer to be used by ASL.
+	 */
+	switch (buffer->prm_cmd) {
+	case PRM_CMD_RUN_SERVICE:
+
+		handler = find_prm_handler(&buffer->handler_guid);
+		module = find_prm_module(&buffer->handler_guid);
+		if (!handler || !module)
+			goto invalid_guid;
+
+		if (!handler->handler_addr) {
+			buffer->prm_status = PRM_HANDLER_ERROR;
+			return AE_OK;
+		}
+
+		ACPI_COPY_NAMESEG(context.signature, "PRMC");
+		context.revision = 0x0;
+		context.reserved = 0x0;
+		context.identifier = handler->guid;
+		context.static_data_buffer = handler->static_data_buffer_addr;
+		context.mmio_ranges = module->mmio_info;
+
+		status = efi_call_acpi_prm_handler(handler->handler_addr,
+						   handler->acpi_param_buffer_addr,
+						   &context);
+		if (status == EFI_SUCCESS) {
+			buffer->prm_status = PRM_HANDLER_SUCCESS;
+		} else {
+			buffer->prm_status = PRM_HANDLER_ERROR;
+			buffer->efi_status = status;
+		}
+		break;
+
+	case PRM_CMD_START_TRANSACTION:
+
+		module = find_prm_module(&buffer->handler_guid);
+		if (!module)
+			goto invalid_guid;
+
+		if (module->updatable)
+			module->updatable = false;
+		else
+			buffer->prm_status = UPDATE_LOCK_ALREADY_HELD;
+		break;
+
+	case PRM_CMD_END_TRANSACTION:
+
+		module = find_prm_module(&buffer->handler_guid);
+		if (!module)
+			goto invalid_guid;
+
+		if (module->updatable)
+			buffer->prm_status = UPDATE_UNLOCK_WITHOUT_LOCK;
+		else
+			module->updatable = true;
+		break;
+
+	default:
+
+		buffer->prm_status = INVALID_PRM_COMMAND;
+		break;
+	}
+
+	return AE_OK;
+
+invalid_guid:
+	buffer->prm_status = PRM_HANDLER_GUID_NOT_FOUND;
+	return AE_OK;
+}
+
+void __init init_prmt(void)
+{
+	struct acpi_table_header *tbl;
+	acpi_status status;
+	int mc;
+
+	status = acpi_get_table(ACPI_SIG_PRMT, 0, &tbl);
+	if (ACPI_FAILURE(status))
+		return;
+
+	mc = acpi_table_parse_entries(ACPI_SIG_PRMT, sizeof(struct acpi_table_prmt) +
+					  sizeof (struct acpi_table_prmt_header),
+					  0, acpi_parse_prmt, 0);
+	acpi_put_table(tbl);
+	/*
+	 * Return immediately if PRMT table is not present or no PRM module found.
+	 */
+	if (mc <= 0)
+		return;
+
+	pr_info("PRM: found %u modules\n", mc);
+
+	if (!efi_enabled(EFI_RUNTIME_SERVICES)) {
+		pr_err("PRM: EFI runtime services unavailable\n");
+		return;
+	}
+
+	status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
+						    ACPI_ADR_SPACE_PLATFORM_RT,
+						    &acpi_platformrt_space_handler,
+						    NULL, NULL);
+	if (ACPI_FAILURE(status))
+		pr_alert("PRM: OperationRegion handler could not be installed\n");
+}