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, 246 insertions, 0 deletions

diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
new file mode 100644
index 000000000..80aeb0d55
--- /dev/null
+++ b/drivers/cxl/Kconfig
@@ -0,0 +1,246 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig CXL_BUS
+	tristate "CXL (Compute Express Link) Devices Support"
+	depends on PCI
+	select FW_LOADER
+	select FW_UPLOAD
+	select PCI_DOE
+	select FIRMWARE_TABLE
+	select NUMA_KEEP_MEMINFO if NUMA_MEMBLKS
+	select FWCTL if CXL_FEATURES
+	help
+	  CXL is a bus that is electrically compatible with PCI Express, but
+	  layers three protocols on that signalling (CXL.io, CXL.cache, and
+	  CXL.mem). The CXL.cache protocol allows devices to hold cachelines
+	  locally, the CXL.mem protocol allows devices to be fully coherent
+	  memory targets, the CXL.io protocol is equivalent to PCI Express.
+	  Say 'y' to enable support for the configuration and management of
+	  devices supporting these protocols.
+
+if CXL_BUS
+
+config CXL_PCI
+	tristate "PCI manageability"
+	default CXL_BUS
+	select CXL_MEM
+	help
+	  The CXL specification defines a "CXL memory device" sub-class in the
+	  PCI "memory controller" base class of devices. Device's identified by
+	  this class code provide support for volatile and / or persistent
+	  memory to be mapped into the system address map (Host-managed Device
+	  Memory (HDM)).
+
+	  Say 'y/m' to enable a driver that will attach to CXL memory expander
+	  devices enumerated by the memory device class code for configuration
+	  and management primarily via the mailbox interface. See Chapter 2.3
+	  Type 3 CXL Device in the CXL 2.0 specification for more details.
+
+	  If unsure say 'm'.
+
+config CXL_MEM_RAW_COMMANDS
+	bool "RAW Command Interface for Memory Devices"
+	depends on CXL_PCI
+	help
+	  Enable CXL RAW command interface.
+
+	  The CXL driver ioctl interface may assign a kernel ioctl command
+	  number for each specification defined opcode. At any given point in
+	  time the number of opcodes that the specification defines and a device
+	  may implement may exceed the kernel's set of associated ioctl function
+	  numbers. The mismatch is either by omission, specification is too new,
+	  or by design. When prototyping new hardware, or developing / debugging
+	  the driver it is useful to be able to submit any possible command to
+	  the hardware, even commands that may crash the kernel due to their
+	  potential impact to memory currently in use by the kernel.
+
+	  If developing CXL hardware or the driver say Y, otherwise say N.
+
+config CXL_ACPI
+	tristate "CXL ACPI: Platform Support"
+	depends on ACPI
+	depends on ACPI_NUMA
+	depends on CXL_PMEM || !CXL_PMEM
+	default CXL_BUS
+	select ACPI_TABLE_LIB
+	select ACPI_HMAT
+	select CXL_PORT
+	help
+	  Enable support for host managed device memory (HDM) resources
+	  published by a platform's ACPI CXL memory layout description.  See
+	  Chapter 9.14.1 CXL Early Discovery Table (CEDT) in the CXL 2.0
+	  specification, and CXL Fixed Memory Window Structures (CEDT.CFMWS)
+	  (https://www.computeexpresslink.org/spec-landing). The CXL core
+	  consumes these resource to publish the root of a cxl_port decode
+	  hierarchy to map regions that represent System RAM, or Persistent
+	  Memory regions to be managed by LIBNVDIMM.
+
+	  If unsure say 'm'.
+
+config CXL_PMEM
+	tristate "CXL PMEM: Persistent Memory Support"
+	depends on LIBNVDIMM
+	default CXL_BUS
+	help
+	  In addition to typical memory resources a platform may also advertise
+	  support for persistent memory attached via CXL. This support is
+	  managed via a bridge driver from CXL to the LIBNVDIMM system
+	  subsystem. Say 'y/m' to enable support for enumerating and
+	  provisioning the persistent memory capacity of CXL memory expanders.
+
+	  If unsure say 'm'.
+
+config CXL_MEM
+	tristate "CXL: Memory Expansion"
+	default CXL_BUS
+	help
+	  The CXL.mem protocol allows a device to act as a provider of "System
+	  RAM" and/or "Persistent Memory" that is fully coherent as if the
+	  memory were attached to the typical CPU memory controller. This is
+	  known as HDM "Host-managed Device Memory".
+
+	  Say 'y/m' to enable a driver that will attach to CXL.mem devices for
+	  memory expansion and control of HDM. See Chapter 9.13 in the CXL 2.0
+	  specification for a detailed description of HDM.
+
+	  If unsure say 'm'.
+
+config CXL_FEATURES
+	bool "CXL: Features"
+	depends on CXL_PCI
+	help
+	  Enable support for CXL Features. A CXL device that includes a mailbox
+	  supports commands that allows listing, getting, and setting of
+	  optionally defined features such as memory sparing or post package
+	  sparing. Vendors may define custom features for the device.
+
+	  If unsure say 'n'
+
+config CXL_EDAC_MEM_FEATURES
+	bool "CXL: EDAC Memory Features"
+	depends on EXPERT
+	depends on CXL_MEM
+	depends on CXL_FEATURES
+	depends on EDAC >= CXL_BUS
+	help
+	  The CXL EDAC memory feature is optional and allows host to
+	  control the EDAC memory features configurations of CXL memory
+	  expander devices.
+
+	  Say 'y' if you have an expert need to change default settings
+	  of a memory RAS feature established by the platform/device.
+	  Otherwise say 'n'.
+
+config CXL_EDAC_SCRUB
+	bool "Enable CXL Patrol Scrub Control (Patrol Read)"
+	depends on CXL_EDAC_MEM_FEATURES
+	depends on EDAC_SCRUB
+	help
+	  The CXL EDAC scrub control is optional and allows host to
+	  control the scrub feature configurations of CXL memory expander
+	  devices.
+
+	  When enabled 'cxl_mem' and 'cxl_region' EDAC devices are
+	  published with memory scrub control attributes as described by
+	  Documentation/ABI/testing/sysfs-edac-scrub.
+
+	  Say 'y' if you have an expert need to change default settings
+	  of a memory scrub feature established by the platform/device
+	  (e.g. scrub rates for the patrol scrub feature).
+	  Otherwise say 'n'.
+
+config CXL_EDAC_ECS
+	bool "Enable CXL Error Check Scrub (Repair)"
+	depends on CXL_EDAC_MEM_FEATURES
+	depends on EDAC_ECS
+	help
+	  The CXL EDAC ECS control is optional and allows host to
+	  control the ECS feature configurations of CXL memory expander
+	  devices.
+
+	  When enabled 'cxl_mem' EDAC devices are published with memory
+	  ECS control attributes as described by
+	  Documentation/ABI/testing/sysfs-edac-ecs.
+
+	  Say 'y' if you have an expert need to change default settings
+	  of a memory ECS feature established by the platform/device.
+	  Otherwise say 'n'.
+
+config CXL_EDAC_MEM_REPAIR
+	bool "Enable CXL Memory Repair"
+	depends on CXL_EDAC_MEM_FEATURES
+	depends on EDAC_MEM_REPAIR
+	help
+	  The CXL EDAC memory repair control is optional and allows host
+	  to control the memory repair features (e.g. sparing, PPR)
+	  configurations of CXL memory expander devices.
+
+	  When enabled, the memory repair feature requires an additional
+	  memory of approximately 43KB to store CXL DRAM and CXL general
+	  media event records.
+
+	  When enabled 'cxl_mem' EDAC devices are published with memory
+	  repair control attributes as described by
+	  Documentation/ABI/testing/sysfs-edac-memory-repair.
+
+	  Say 'y' if you have an expert need to change default settings
+	  of a memory repair feature established by the platform/device.
+	  Otherwise say 'n'.
+
+config CXL_PORT
+	default CXL_BUS
+	tristate
+
+config CXL_SUSPEND
+	def_bool y
+	depends on SUSPEND && CXL_MEM
+
+config CXL_REGION
+	bool "CXL: Region Support"
+	default CXL_BUS
+	# For MAX_PHYSMEM_BITS
+	depends on SPARSEMEM
+	select MEMREGION
+	select GET_FREE_REGION
+	help
+	  Enable the CXL core to enumerate and provision CXL regions. A CXL
+	  region is defined by one or more CXL expanders that decode a given
+	  system-physical address range. For CXL regions established by
+	  platform-firmware this option enables memory error handling to
+	  identify the devices participating in a given interleaved memory
+	  range. Otherwise, platform-firmware managed CXL is enabled by being
+	  placed in the system address map and does not need a driver.
+
+	  If unsure say 'y'
+
+config CXL_REGION_INVALIDATION_TEST
+	bool "CXL: Region Cache Management Bypass (TEST)"
+	depends on CXL_REGION
+	help
+	  CXL Region management and security operations potentially invalidate
+	  the content of CPU caches without notifying those caches to
+	  invalidate the affected cachelines. The CXL Region driver attempts
+	  to invalidate caches when those events occur.  If that invalidation
+	  fails the region will fail to enable.  Reasons for cache
+	  invalidation failure are due to the CPU not providing a cache
+	  invalidation mechanism. For example usage of wbinvd is restricted to
+	  bare metal x86. However, for testing purposes toggling this option
+	  can disable that data integrity safety and proceed with enabling
+	  regions when there might be conflicting contents in the CPU cache.
+
+	  If unsure, or if this kernel is meant for production environments,
+	  say N.
+
+config CXL_MCE
+	def_bool y
+	depends on X86_MCE && MEMORY_FAILURE
+
+config CXL_RAS
+	def_bool y
+	depends on ACPI_APEI_GHES && PCIEAER && CXL_BUS
+
+config CXL_ATL
+	def_bool y
+	depends on CXL_REGION
+	depends on ACPI_PRMT && AMD_NB
+
+endif