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, 167 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-qat b/Documentation/ABI/testing/sysfs-driver-qat
new file mode 100644
index 000000000..b0561b9fc
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-qat
@@ -0,0 +1,167 @@
+What:		/sys/bus/pci/devices/<BDF>/qat/state
+Date:		June 2022
+KernelVersion:	6.0
+Contact:	qat-linux@intel.com
+Description:	(RW) Reports the current state of the QAT device. Write to
+		the file to start or stop the device.
+
+		The values are:
+
+		* up: the device is up and running
+		* down: the device is down
+
+
+		It is possible to transition the device from up to down only
+		if the device is up and vice versa.
+
+		This attribute is available for qat_4xxx and qat_6xxx devices.
+
+What:		/sys/bus/pci/devices/<BDF>/qat/cfg_services
+Date:		June 2022
+KernelVersion:	6.0
+Contact:	qat-linux@intel.com
+Description:	(RW) Reports the current configuration of the QAT device.
+		Write to the file to change the configured services.
+
+		One or more services can be enabled per device.
+		Certain configurations are restricted to specific device types;
+		where applicable this is explicitly indicated, for example
+		(qat_6xxx) denotes applicability exclusively to that device series.
+
+		The available services include:
+
+		* sym: Configures the device for symmetric cryptographic operations.
+		* asym: Configures the device for asymmetric cryptographic operations.
+		* dc: Configures the device for compression and decompression
+		  operations.
+		* dcc: Similar to dc, but with the additional dc chaining feature
+		  enabled, cipher then compress (qat_6xxx), hash then compression.
+		  If this is not required choose dc.
+		* decomp: Configures the device for decompression operations (qat_6xxx).
+
+		Service combinations are permitted for all services except dcc.
+		On QAT GEN4 devices (qat_4xxx driver) a maximum of two services can be
+		combined and on QAT GEN6 devices (qat_6xxx driver ) a maximum of three
+		services can be combined.
+		The order of services is not significant. For instance, sym;asym is
+		functionally equivalent to asym;sym.
+
+		It is possible to set the configuration only if the device
+		is in the `down` state (see /sys/bus/pci/devices/<BDF>/qat/state)
+
+		The following example shows how to change the configuration of
+		a device configured for running crypto services in order to
+		run data compression::
+
+			# cat /sys/bus/pci/devices/<BDF>/qat/state
+			up
+			# cat /sys/bus/pci/devices/<BDF>/qat/cfg_services
+			sym;asym
+			# echo down > /sys/bus/pci/devices/<BDF>/qat/state
+			# echo dc > /sys/bus/pci/devices/<BDF>/qat/cfg_services
+			# echo up > /sys/bus/pci/devices/<BDF>/qat/state
+			# cat /sys/bus/pci/devices/<BDF>/qat/cfg_services
+			dc
+
+		This attribute is available for qat_4xxx and qat_6xxx devices.
+
+What:		/sys/bus/pci/devices/<BDF>/qat/pm_idle_enabled
+Date:		June 2023
+KernelVersion:	6.5
+Contact:	qat-linux@intel.com
+Description:	(RW) This configuration option provides a way to force the device into remaining in
+		the MAX power state.
+		If idle support is enabled the device will transition to the `MIN` power state when
+		idle, otherwise will stay in the MAX power state.
+		Write to the file to enable or disable idle support.
+
+		The values are:
+
+		* 0: idle support is disabled
+		* 1: idle support is enabled
+
+		Default value is 1.
+
+		It is possible to set the pm_idle_enabled value only if the device
+		is in the `down` state (see /sys/bus/pci/devices/<BDF>/qat/state)
+
+		The following example shows how to change the pm_idle_enabled of
+		a device::
+
+			# cat /sys/bus/pci/devices/<BDF>/qat/state
+			up
+			# cat /sys/bus/pci/devices/<BDF>/qat/pm_idle_enabled
+			1
+			# echo down > /sys/bus/pci/devices/<BDF>/qat/state
+			# echo 0 > /sys/bus/pci/devices/<BDF>/qat/pm_idle_enabled
+			# echo up > /sys/bus/pci/devices/<BDF>/qat/state
+			# cat /sys/bus/pci/devices/<BDF>/qat/pm_idle_enabled
+			0
+
+		This attribute is available for qat_4xxx and qat_6xxx devices.
+
+What:		/sys/bus/pci/devices/<BDF>/qat/rp2srv
+Date:		January 2024
+KernelVersion:	6.7
+Contact:	qat-linux@intel.com
+Description:
+		(RW) This attribute provides a way for a user to query a
+		specific ring pair for the type of service that it is currently
+		configured for.
+
+		When written to, the value is cached and used to perform the
+		read operation. Allowed values are in the range 0 to N-1, where
+		N is the max number of ring pairs supported by a device. This
+		can be queried using the attribute qat/num_rps.
+
+		A read returns the service associated to the ring pair queried.
+
+		The values are:
+
+		* dc: the ring pair is configured for running compression services
+		* sym: the ring pair is configured for running symmetric crypto
+		  services
+		* asym: the ring pair is configured for running asymmetric crypto
+		  services
+
+		Example usage::
+
+			# echo 1 > /sys/bus/pci/devices/<BDF>/qat/rp2srv
+			# cat /sys/bus/pci/devices/<BDF>/qat/rp2srv
+			sym
+
+		This attribute is available for qat_4xxx and qat_6xxx devices.
+
+What:		/sys/bus/pci/devices/<BDF>/qat/num_rps
+Date:		January 2024
+KernelVersion:	6.7
+Contact:	qat-linux@intel.com
+Description:
+		(RO) Returns the number of ring pairs that a single device has.
+
+		Example usage::
+
+			# cat /sys/bus/pci/devices/<BDF>/qat/num_rps
+			64
+
+		This attribute is available for qat_4xxx and qat_6xxx devices.
+
+What:		/sys/bus/pci/devices/<BDF>/qat/auto_reset
+Date:		May 2024
+KernelVersion:	6.9
+Contact:	qat-linux@intel.com
+Description:	(RW) Reports the current state of the autoreset feature
+		for a QAT device
+
+		Write to the attribute to enable or disable device auto reset.
+
+		Device auto reset is disabled by default.
+
+		The values are:
+
+		* 1/Yy/on: auto reset enabled. If the device encounters an
+		  unrecoverable error, it will be reset automatically.
+		* 0/Nn/off: auto reset disabled. If the device encounters an
+		  unrecoverable error, it will not be reset.
+
+		This attribute is available for qat_4xxx and qat_6xxx devices.