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, 105 insertions, 0 deletions

diff --git a/drivers/scsi/st_options.h b/drivers/scsi/st_options.h
new file mode 100644
index 000000000..2b6cabd7b
--- /dev/null
+++ b/drivers/scsi/st_options.h
@@ -0,0 +1,105 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+   The compile-time configurable defaults for the Linux SCSI tape driver.
+
+   Copyright 1995-2003 Kai Makisara.
+
+   Last modified: Thu Feb 21 21:47:07 2008 by kai.makisara
+*/
+
+#ifndef _ST_OPTIONS_H
+#define _ST_OPTIONS_H
+
+/* If TRY_DIRECT_IO is non-zero, the driver tries to transfer data directly
+   between the user buffer and tape drive. If this is not possible, driver
+   buffer is used. If TRY_DIRECT_IO is zero, driver buffer is always used. */
+#define TRY_DIRECT_IO 1
+
+/* The driver does not wait for some operations to finish before returning
+   to the user program if ST_NOWAIT is non-zero. This helps if the SCSI
+   adapter does not support multiple outstanding commands. However, the user
+   should not give a new tape command before the previous one has finished. */
+#define ST_NOWAIT 0
+
+/* If ST_IN_FILE_POS is nonzero, the driver positions the tape after the
+   record been read by the user program even if the tape has moved further
+   because of buffered reads. Should be set to zero to support also drives
+   that can't space backwards over records. NOTE: The tape will be
+   spaced backwards over an "accidentally" crossed filemark in any case. */
+#define ST_IN_FILE_POS 0
+
+/* If ST_RECOVERED_WRITE_FATAL is non-zero, recovered errors while writing
+   are considered "hard errors". */
+#define ST_RECOVERED_WRITE_FATAL 0
+
+/* The "guess" for the block size for devices that don't support MODE
+   SENSE. */
+#define ST_DEFAULT_BLOCK 0
+
+/* The minimum tape driver buffer size in kilobytes in fixed block mode.
+   Must be non-zero. */
+#define ST_FIXED_BUFFER_BLOCKS 32
+
+/* Maximum number of scatter/gather segments */
+#define ST_MAX_SG      256
+
+/* The number of scatter/gather segments to allocate at first try (must be
+   smaller or equal to the maximum). */
+#define ST_FIRST_SG    8
+
+/* The size of the first scatter/gather segments (determines the maximum block
+   size for SCSI adapters not supporting scatter/gather). The default is set
+   to try to allocate the buffer as one chunk. */
+#define ST_FIRST_ORDER  5
+
+
+/* The following lines define defaults for properties that can be set
+   separately for each drive using the MTSTOPTIONS ioctl. */
+
+/* If ST_TWO_FM is non-zero, the driver writes two filemarks after a
+   file being written. Some drives can't handle two filemarks at the
+   end of data. */
+#define ST_TWO_FM 0
+
+/* If ST_BUFFER_WRITES is non-zero, writes in fixed block mode are
+   buffered until the driver buffer is full or asynchronous write is
+   triggered. May make detection of End-Of-Medium early enough fail. */
+#define ST_BUFFER_WRITES 1
+
+/* If ST_ASYNC_WRITES is non-zero, the SCSI write command may be started
+   without waiting for it to finish. May cause problems in multiple
+   tape backups. */
+#define ST_ASYNC_WRITES 1
+
+/* If ST_READ_AHEAD is non-zero, blocks are read ahead in fixed block
+   mode. */
+#define ST_READ_AHEAD 1
+
+/* If ST_AUTO_LOCK is non-zero, the drive door is locked at the first
+   read or write command after the device is opened. The door is opened
+   when the device is closed. */
+#define ST_AUTO_LOCK 0
+
+/* If ST_FAST_MTEOM is non-zero, the MTEOM ioctl is done using the
+   direct SCSI command. The file number status is lost but this method
+   is fast with some drives. Otherwise MTEOM is done by spacing over
+   files and the file number status is retained. */
+#define ST_FAST_MTEOM 0
+
+/* If ST_SCSI2LOGICAL is nonzero, the logical block addresses are used for
+   MTIOCPOS and MTSEEK by default. Vendor addresses are used if ST_SCSI2LOGICAL
+   is zero. */
+#define ST_SCSI2LOGICAL 0
+
+/* If ST_SYSV is non-zero, the tape behaves according to the SYS V semantics.
+   The default is BSD semantics. */
+#define ST_SYSV 0
+
+/* If ST_SILI is non-zero, the SILI bit is set when reading in variable block
+   mode and the block size is determined using the residual returned by the HBA. */
+#define ST_SILI 0
+
+/* Time to wait for the drive to become ready if blocking open */
+#define ST_BLOCK_SECONDS     120
+
+#endif