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, 387 insertions, 0 deletions

diff --git a/drivers/mtd/ubi/debug.h b/drivers/mtd/ubi/debug.h
new file mode 100644
index 000000000..b2fd97548
--- /dev/null
+++ b/drivers/mtd/ubi/debug.h
@@ -0,0 +1,387 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * Author: Artem Bityutskiy (Битюцкий Артём)
+ */
+
+#ifndef __UBI_DEBUG_H__
+#define __UBI_DEBUG_H__
+
+void ubi_dump_flash(struct ubi_device *ubi, int pnum, int offset, int len);
+void ubi_dump_ec_hdr(const struct ubi_ec_hdr *ec_hdr);
+void ubi_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr);
+
+#include <linux/random.h>
+
+#define ubi_assert(expr)  do {                                               \
+	if (unlikely(!(expr))) {                                             \
+		pr_crit("UBI assert failed in %s at %u (pid %d)\n",          \
+		       __func__, __LINE__, current->pid);                    \
+		dump_stack();                                                \
+	}                                                                    \
+} while (0)
+
+#define ubi_dbg_print_hex_dump(l, ps, pt, r, g, b, len, a)                   \
+		print_hex_dump(l, ps, pt, r, g, b, len, a)
+
+#define ubi_dbg_msg(type, fmt, ...) \
+	pr_debug("UBI DBG " type " (pid %d): " fmt "\n", current->pid,       \
+		 ##__VA_ARGS__)
+
+/* General debugging messages */
+#define dbg_gen(fmt, ...) ubi_dbg_msg("gen", fmt, ##__VA_ARGS__)
+/* Messages from the eraseblock association sub-system */
+#define dbg_eba(fmt, ...) ubi_dbg_msg("eba", fmt, ##__VA_ARGS__)
+/* Messages from the wear-leveling sub-system */
+#define dbg_wl(fmt, ...)  ubi_dbg_msg("wl", fmt, ##__VA_ARGS__)
+/* Messages from the input/output sub-system */
+#define dbg_io(fmt, ...)  ubi_dbg_msg("io", fmt, ##__VA_ARGS__)
+/* Initialization and build messages */
+#define dbg_bld(fmt, ...) ubi_dbg_msg("bld", fmt, ##__VA_ARGS__)
+
+void ubi_dump_vol_info(const struct ubi_volume *vol);
+void ubi_dump_vtbl_record(const struct ubi_vtbl_record *r, int idx);
+void ubi_dump_av(const struct ubi_ainf_volume *av);
+void ubi_dump_aeb(const struct ubi_ainf_peb *aeb, int type);
+void ubi_dump_mkvol_req(const struct ubi_mkvol_req *req);
+int ubi_self_check_all_ff(struct ubi_device *ubi, int pnum, int offset,
+			  int len);
+int ubi_debugfs_init(void);
+void ubi_debugfs_exit(void);
+int ubi_debugfs_init_dev(struct ubi_device *ubi);
+void ubi_debugfs_exit_dev(struct ubi_device *ubi);
+
+/**
+ * The following function is a legacy implementation of UBI fault-injection
+ * hook. When using more powerful fault injection capabilities, the legacy
+ * fault injection interface should be retained.
+ */
+int ubi_dbg_power_cut(struct ubi_device *ubi, int caller);
+
+static inline int ubi_dbg_bitflip(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_bitflips)
+		return !get_random_u32_below(200);
+	return 0;
+}
+
+static inline int ubi_dbg_write_failure(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_io_failures)
+		return !get_random_u32_below(500);
+	return 0;
+}
+
+static inline int ubi_dbg_erase_failure(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_io_failures)
+		return !get_random_u32_below(400);
+	return 0;
+}
+
+/**
+ * MASK_XXX: Mask for emulate_failures in ubi_debug_info.The mask is used to
+ * precisely control the type and process of fault injection.
+ */
+/* Emulate a power cut when writing EC/VID header */
+#define MASK_POWER_CUT_EC			(1 << 0)
+#define MASK_POWER_CUT_VID			(1 << 1)
+/* Emulate a power cut when writing data*/
+#define MASK_POWER_CUT_DATA			(1 << 2)
+/* Emulate bit-flips */
+#define MASK_BITFLIPS				(1 << 3)
+/* Emulate ecc error */
+#define MASK_ECCERR				(1 << 4)
+/* Emulates -EIO during data read */
+#define MASK_READ_FAILURE			(1 << 5)
+#define MASK_READ_FAILURE_EC			(1 << 6)
+#define MASK_READ_FAILURE_VID			(1 << 7)
+/* Emulates -EIO during data write */
+#define MASK_WRITE_FAILURE			(1 << 8)
+/* Emulates -EIO during erase a PEB*/
+#define MASK_ERASE_FAILURE			(1 << 9)
+/* Return UBI_IO_FF when reading EC/VID header */
+#define MASK_IO_FF_EC				(1 << 10)
+#define MASK_IO_FF_VID				(1 << 11)
+/* Return UBI_IO_FF_BITFLIPS when reading EC/VID header */
+#define MASK_IO_FF_BITFLIPS_EC			(1 << 12)
+#define MASK_IO_FF_BITFLIPS_VID			(1 << 13)
+/* Return UBI_IO_BAD_HDR when reading EC/VID header */
+#define MASK_BAD_HDR_EC				(1 << 14)
+#define MASK_BAD_HDR_VID			(1 << 15)
+/* Return UBI_IO_BAD_HDR_EBADMSG when reading EC/VID header */
+#define MASK_BAD_HDR_EBADMSG_EC			(1 << 16)
+#define MASK_BAD_HDR_EBADMSG_VID		(1 << 17)
+
+#ifdef CONFIG_MTD_UBI_FAULT_INJECTION
+
+extern bool should_fail_eccerr(void);
+extern bool should_fail_bitflips(void);
+extern bool should_fail_read_failure(void);
+extern bool should_fail_write_failure(void);
+extern bool should_fail_erase_failure(void);
+extern bool should_fail_power_cut(void);
+extern bool should_fail_io_ff(void);
+extern bool should_fail_io_ff_bitflips(void);
+extern bool should_fail_bad_hdr(void);
+extern bool should_fail_bad_hdr_ebadmsg(void);
+
+static inline bool ubi_dbg_fail_bitflip(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_failures & MASK_BITFLIPS)
+		return should_fail_bitflips();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_write(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_failures & MASK_WRITE_FAILURE)
+		return should_fail_write_failure();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_erase(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_failures & MASK_ERASE_FAILURE)
+		return should_fail_erase_failure();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_power_cut(const struct ubi_device *ubi,
+					  unsigned int caller)
+{
+	if (ubi->dbg.emulate_failures & caller)
+		return should_fail_power_cut();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_read(const struct ubi_device *ubi,
+				     unsigned int caller)
+{
+	if (ubi->dbg.emulate_failures & caller)
+		return should_fail_read_failure();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_eccerr(const struct ubi_device *ubi)
+{
+	if (ubi->dbg.emulate_failures & MASK_ECCERR)
+		return should_fail_eccerr();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_ff(const struct ubi_device *ubi,
+				   unsigned int caller)
+{
+	if (ubi->dbg.emulate_failures & caller)
+		return should_fail_io_ff();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_ff_bitflips(const struct ubi_device *ubi,
+					    unsigned int caller)
+{
+	if (ubi->dbg.emulate_failures & caller)
+		return should_fail_io_ff_bitflips();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_bad_hdr(const struct ubi_device *ubi,
+					 unsigned int caller)
+{
+	if (ubi->dbg.emulate_failures & caller)
+		return should_fail_bad_hdr();
+	return false;
+}
+
+static inline bool ubi_dbg_fail_bad_hdr_ebadmsg(const struct ubi_device *ubi,
+						 unsigned int caller)
+{
+	if (ubi->dbg.emulate_failures & caller)
+		return should_fail_bad_hdr_ebadmsg();
+	return false;
+}
+#else /* CONFIG_MTD_UBI_FAULT_INJECTION */
+
+#define ubi_dbg_fail_bitflip(u)             false
+#define ubi_dbg_fail_write(u)               false
+#define ubi_dbg_fail_erase(u)               false
+#define ubi_dbg_fail_power_cut(u, c)        false
+#define ubi_dbg_fail_read(u, c)             false
+#define ubi_dbg_fail_eccerr(u)              false
+#define ubi_dbg_fail_ff(u, c)               false
+#define ubi_dbg_fail_ff_bitflips(u, v)      false
+#define ubi_dbg_fail_bad_hdr(u, c)          false
+#define ubi_dbg_fail_bad_hdr_ebadmsg(u, c)  false
+
+#endif
+
+/**
+ * ubi_dbg_is_power_cut - if it is time to emulate power cut.
+ * @ubi: UBI device description object
+ *
+ * Returns true if power cut should be emulated, otherwise returns false.
+ */
+static inline bool ubi_dbg_is_power_cut(struct ubi_device *ubi,
+					unsigned int caller)
+{
+	if (ubi_dbg_power_cut(ubi, caller))
+		return true;
+	return ubi_dbg_fail_power_cut(ubi, caller);
+}
+
+/**
+ * ubi_dbg_is_bitflip - if it is time to emulate a bit-flip.
+ * @ubi: UBI device description object
+ *
+ * Returns true if a bit-flip should be emulated, otherwise returns false.
+ */
+static inline bool ubi_dbg_is_bitflip(const struct ubi_device *ubi)
+{
+	if (ubi_dbg_bitflip(ubi))
+		return true;
+	return ubi_dbg_fail_bitflip(ubi);
+}
+
+/**
+ * ubi_dbg_is_write_failure - if it is time to emulate a write failure.
+ * @ubi: UBI device description object
+ *
+ * Returns true if a write failure should be emulated, otherwise returns
+ * false.
+ */
+static inline bool ubi_dbg_is_write_failure(const struct ubi_device *ubi)
+{
+	if (ubi_dbg_write_failure(ubi))
+		return true;
+	return ubi_dbg_fail_write(ubi);
+}
+
+/**
+ * ubi_dbg_is_erase_failure - if its time to emulate an erase failure.
+ * @ubi: UBI device description object
+ *
+ * Returns true if an erase failure should be emulated, otherwise returns
+ * false.
+ */
+static inline bool ubi_dbg_is_erase_failure(const struct ubi_device *ubi)
+{
+	if (ubi_dbg_erase_failure(ubi))
+		return true;
+	return ubi_dbg_fail_erase(ubi);
+}
+
+/**
+ * ubi_dbg_is_eccerr - if it is time to emulate ECC error.
+ * @ubi: UBI device description object
+ *
+ * Returns true if a ECC error should be emulated, otherwise returns false.
+ */
+static inline bool ubi_dbg_is_eccerr(const struct ubi_device *ubi)
+{
+	return ubi_dbg_fail_eccerr(ubi);
+}
+
+/**
+ * ubi_dbg_is_read_failure - if it is time to emulate a read failure.
+ * @ubi: UBI device description object
+ *
+ * Returns true if a read failure should be emulated, otherwise returns
+ * false.
+ */
+static inline bool ubi_dbg_is_read_failure(const struct ubi_device *ubi,
+					   unsigned int caller)
+{
+	return ubi_dbg_fail_read(ubi, caller);
+}
+
+/**
+ * ubi_dbg_is_ff - if it is time to emulate that read region is only 0xFF.
+ * @ubi: UBI device description object
+ *
+ * Returns true if read region should be emulated 0xFF, otherwise
+ * returns false.
+ */
+static inline bool ubi_dbg_is_ff(const struct ubi_device *ubi,
+				 unsigned int caller)
+{
+	return ubi_dbg_fail_ff(ubi, caller);
+}
+
+/**
+ * ubi_dbg_is_ff_bitflips - if it is time to emulate that read region is only 0xFF
+ * with error reported by the MTD driver
+ *
+ * @ubi: UBI device description object
+ *
+ * Returns true if read region should be emulated 0xFF and error
+ * reported by the MTD driver, otherwise returns false.
+ */
+static inline bool ubi_dbg_is_ff_bitflips(const struct ubi_device *ubi,
+					  unsigned int caller)
+{
+	return ubi_dbg_fail_ff_bitflips(ubi, caller);
+}
+
+/**
+ * ubi_dbg_is_bad_hdr - if it is time to emulate a bad header
+ * @ubi: UBI device description object
+ *
+ * Returns true if a bad header error should be emulated, otherwise
+ * returns false.
+ */
+static inline bool ubi_dbg_is_bad_hdr(const struct ubi_device *ubi,
+				      unsigned int caller)
+{
+	return ubi_dbg_fail_bad_hdr(ubi, caller);
+}
+
+/**
+ * ubi_dbg_is_bad_hdr_ebadmsg - if it is time to emulate a bad header with
+ * ECC error.
+ *
+ * @ubi: UBI device description object
+ *
+ * Returns true if a bad header with ECC error should be emulated, otherwise
+ * returns false.
+ */
+static inline bool ubi_dbg_is_bad_hdr_ebadmsg(const struct ubi_device *ubi,
+					      unsigned int caller)
+{
+	return ubi_dbg_fail_bad_hdr_ebadmsg(ubi, caller);
+}
+
+/**
+ * ubi_dbg_is_bgt_disabled - if the background thread is disabled.
+ * @ubi: UBI device description object
+ *
+ * Returns non-zero if the UBI background thread is disabled for testing
+ * purposes.
+ */
+static inline int ubi_dbg_is_bgt_disabled(const struct ubi_device *ubi)
+{
+	return ubi->dbg.disable_bgt;
+}
+
+static inline int ubi_dbg_chk_io(const struct ubi_device *ubi)
+{
+	return ubi->dbg.chk_io;
+}
+
+static inline int ubi_dbg_chk_gen(const struct ubi_device *ubi)
+{
+	return ubi->dbg.chk_gen;
+}
+
+static inline int ubi_dbg_chk_fastmap(const struct ubi_device *ubi)
+{
+	return ubi->dbg.chk_fastmap;
+}
+
+static inline void ubi_enable_dbg_chk_fastmap(struct ubi_device *ubi)
+{
+	ubi->dbg.chk_fastmap = 1;
+}
+
+#endif /* !__UBI_DEBUG_H__ */