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, 376 insertions, 0 deletions

diff --git a/drivers/net/arcnet/arcdevice.h b/drivers/net/arcnet/arcdevice.h
new file mode 100644
index 000000000..a7c217359
--- /dev/null
+++ b/drivers/net/arcnet/arcdevice.h
@@ -0,0 +1,376 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * INET         An implementation of the TCP/IP protocol suite for the LINUX
+ *              operating system.  NET  is implemented using the  BSD Socket
+ *              interface as the means of communication with the user level.
+ *
+ *              Definitions used by the ARCnet driver.
+ *
+ * Authors:     Avery Pennarun and David Woodhouse
+ */
+#ifndef _LINUX_ARCDEVICE_H
+#define _LINUX_ARCDEVICE_H
+
+#include <asm/timex.h>
+#include <linux/if_arcnet.h>
+
+#ifdef __KERNEL__
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+
+/*
+ * RECON_THRESHOLD is the maximum number of RECON messages to receive
+ * within one minute before printing a "cabling problem" warning. The
+ * default value should be fine.
+ *
+ * After that, a "cabling restored" message will be printed on the next IRQ
+ * if no RECON messages have been received for 10 seconds.
+ *
+ * Do not define RECON_THRESHOLD at all if you want to disable this feature.
+ */
+#define RECON_THRESHOLD 30
+
+/*
+ * Define this to the minimum "timeout" value.  If a transmit takes longer
+ * than TX_TIMEOUT jiffies, Linux will abort the TX and retry.  On a large
+ * network, or one with heavy network traffic, this timeout may need to be
+ * increased.  The larger it is, though, the longer it will be between
+ * necessary transmits - don't set this too high.
+ */
+#define TX_TIMEOUT (HZ * 200 / 1000)
+
+/* Display warnings about the driver being an ALPHA version. */
+#undef ALPHA_WARNING
+
+/*
+ * Debugging bitflags: each option can be enabled individually.
+ *
+ * Note: only debug flags included in the ARCNET_DEBUG_MAX define will
+ *   actually be available.  GCC will (at least, GCC 2.7.0 will) notice
+ *   lines using a BUGLVL not in ARCNET_DEBUG_MAX and automatically optimize
+ *   them out.
+ */
+#define D_NORMAL	1	/* important operational info             */
+#define D_EXTRA		2	/* useful, but non-vital information      */
+#define	D_INIT		4	/* show init/probe messages               */
+#define D_INIT_REASONS	8	/* show reasons for discarding probes     */
+#define D_RECON		32	/* print a message whenever token is lost */
+#define D_PROTO		64	/* debug auto-protocol support            */
+/* debug levels below give LOTS of output during normal operation! */
+#define D_DURING	128	/* trace operations (including irq's)     */
+#define D_TX	        256	/* show tx packets                        */
+#define D_RX		512	/* show rx packets                        */
+#define D_SKB		1024	/* show skb's                             */
+#define D_SKB_SIZE	2048	/* show skb sizes			  */
+#define D_TIMING	4096	/* show time needed to copy buffers to card */
+#define D_DEBUG         8192    /* Very detailed debug line for line */
+
+#ifndef ARCNET_DEBUG_MAX
+#define ARCNET_DEBUG_MAX (127)	/* change to ~0 if you want detailed debugging */
+#endif
+
+#ifndef ARCNET_DEBUG
+#define ARCNET_DEBUG (D_NORMAL | D_EXTRA)
+#endif
+extern int arcnet_debug;
+
+#define BUGLVL(x)	((x) & ARCNET_DEBUG_MAX & arcnet_debug)
+
+/* macros to simplify debug checking */
+#define arc_printk(x, dev, fmt, ...)					\
+do {									\
+	if (BUGLVL(x)) {						\
+		if ((x) == D_NORMAL)					\
+			netdev_warn(dev, fmt, ##__VA_ARGS__);		\
+		else if ((x) < D_DURING)				\
+			netdev_info(dev, fmt, ##__VA_ARGS__);		\
+		else							\
+			netdev_dbg(dev, fmt, ##__VA_ARGS__);		\
+	}								\
+} while (0)
+
+#define arc_cont(x, fmt, ...)						\
+do {									\
+	if (BUGLVL(x))							\
+		pr_cont(fmt, ##__VA_ARGS__);				\
+} while (0)
+
+/* see how long a function call takes to run, expressed in CPU cycles */
+#define TIME(dev, name, bytes, call)					\
+do {									\
+	if (BUGLVL(D_TIMING)) {						\
+		unsigned long _x, _y;					\
+		_x = get_cycles();					\
+		call;							\
+		_y = get_cycles();					\
+		arc_printk(D_TIMING, dev,				\
+			   "%s: %d bytes in %lu cycles == %lu Kbytes/100Mcycle\n", \
+			   name, bytes, _y - _x,			\
+			   100000000 / 1024 * bytes / (_y - _x + 1));	\
+	} else {							\
+		call;							\
+	}								\
+} while (0)
+
+/*
+ * Time needed to reset the card - in ms (milliseconds).  This works on my
+ * SMC PC100.  I can't find a reference that tells me just how long I
+ * should wait.
+ */
+#define RESETtime (300)
+
+/*
+ * These are the max/min lengths of packet payload, not including the
+ * arc_hardware header, but definitely including the soft header.
+ *
+ * Note: packet sizes 254, 255, 256 are impossible because of the way
+ * ARCnet registers work  That's why RFC1201 defines "exception" packets.
+ * In non-RFC1201 protocols, we have to just tack some extra bytes on the
+ * end.
+ */
+#define MTU	253		/* normal packet max size */
+#define MinTU	257		/* extended packet min size */
+#define XMTU	508		/* extended packet max size */
+
+/* status/interrupt mask bit fields */
+#define TXFREEflag	0x01	/* transmitter available */
+#define TXACKflag       0x02	/* transmitted msg. ackd */
+#define RECONflag       0x04	/* network reconfigured */
+#define TESTflag        0x08	/* test flag */
+#define EXCNAKflag      0x08    /* excessive nak flag */
+#define RESETflag       0x10	/* power-on-reset */
+#define RES1flag        0x20	/* reserved - usually set by jumper */
+#define RES2flag        0x40	/* reserved - usually set by jumper */
+#define NORXflag        0x80	/* receiver inhibited */
+
+/* Flags used for IO-mapped memory operations */
+#define AUTOINCflag     0x40	/* Increase location with each access */
+#define IOMAPflag       0x02	/* (for 90xx) Use IO mapped memory, not mmap */
+#define ENABLE16flag    0x80	/* (for 90xx) Enable 16-bit mode */
+
+/* in the command register, the following bits have these meanings:
+ *                0-2     command
+ *                3-4     page number (for enable rcv/xmt command)
+ *                 7      receive broadcasts
+ */
+#define NOTXcmd         0x01	/* disable transmitter */
+#define NORXcmd         0x02	/* disable receiver */
+#define TXcmd           0x03	/* enable transmitter */
+#define RXcmd           0x04	/* enable receiver */
+#define CONFIGcmd       0x05	/* define configuration */
+#define CFLAGScmd       0x06	/* clear flags */
+#define TESTcmd         0x07	/* load test flags */
+#define STARTIOcmd      0x18	/* start internal operation */
+
+/* flags for "clear flags" command */
+#define RESETclear      0x08	/* power-on-reset */
+#define CONFIGclear     0x10	/* system reconfigured */
+
+#define EXCNAKclear     0x0E    /* Clear and acknowledge the excessive nak bit */
+
+/* flags for "load test flags" command */
+#define TESTload        0x08	/* test flag (diagnostic) */
+
+/* byte deposited into first address of buffers on reset */
+#define TESTvalue       0321	/* that's octal for 0xD1 :) */
+
+/* for "enable receiver" command */
+#define RXbcasts        0x80	/* receive broadcasts */
+
+/* flags for "define configuration" command */
+#define NORMALconf      0x00	/* 1-249 byte packets */
+#define EXTconf         0x08	/* 250-504 byte packets */
+
+/* card feature flags, set during auto-detection.
+ * (currently only used by com20020pci)
+ */
+#define ARC_IS_5MBIT    1   /* card default speed is 5MBit */
+#define ARC_CAN_10MBIT  2   /* card uses COM20022, supporting 10MBit,
+				 but default is 2.5MBit. */
+#define ARC_HAS_LED     4   /* card has software controlled LEDs */
+#define ARC_HAS_ROTARY  8   /* card has rotary encoder */
+
+/* information needed to define an encapsulation driver */
+struct ArcProto {
+	char suffix;		/* a for RFC1201, e for ether-encap, etc. */
+	int mtu;		/* largest possible packet */
+	int is_ip;              /* This is an ip plugin - not a raw thing */
+
+	void (*rx)(struct net_device *dev, int bufnum,
+		   struct archdr *pkthdr, int length);
+	int (*build_header)(struct sk_buff *skb, struct net_device *dev,
+			    unsigned short ethproto, uint8_t daddr);
+
+	/* these functions return '1' if the skb can now be freed */
+	int (*prepare_tx)(struct net_device *dev, struct archdr *pkt,
+			  int length, int bufnum);
+	int (*continue_tx)(struct net_device *dev, int bufnum);
+	int (*ack_tx)(struct net_device *dev, int acked);
+};
+
+extern struct ArcProto *arc_proto_map[256], *arc_proto_default,
+	*arc_bcast_proto, *arc_raw_proto;
+
+/*
+ * "Incoming" is information needed for each address that could be sending
+ * to us.  Mostly for partially-received split packets.
+ */
+struct Incoming {
+	struct sk_buff *skb;	/* packet data buffer             */
+	__be16 sequence;	/* sequence number of assembly    */
+	uint8_t lastpacket,	/* number of last packet (from 1) */
+		numpackets;	/* number of packets in split     */
+};
+
+/* only needed for RFC1201 */
+struct Outgoing {
+	struct ArcProto *proto;	/* protocol driver that owns this:
+				 *   if NULL, no packet is pending.
+				 */
+	struct sk_buff *skb;	/* buffer from upper levels */
+	struct archdr *pkt;	/* a pointer into the skb */
+	uint16_t length,	/* bytes total */
+		dataleft,	/* bytes left */
+		segnum,		/* segment being sent */
+		numsegs;	/* number of segments */
+};
+
+#define ARCNET_LED_NAME_SZ (IFNAMSIZ + 6)
+
+struct arcnet_local {
+	uint8_t config,		/* current value of CONFIG register */
+		timeout,	/* Extended timeout for COM20020 */
+		backplane,	/* Backplane flag for COM20020 */
+		clockp,		/* COM20020 clock divider */
+		clockm,		/* COM20020 clock multiplier flag */
+		setup,		/* Contents of setup1 register */
+		setup2,		/* Contents of setup2 register */
+		intmask;	/* current value of INTMASK register */
+	uint8_t default_proto[256];	/* default encap to use for each host */
+	int	cur_tx,		/* buffer used by current transmit, or -1 */
+		next_tx,	/* buffer where a packet is ready to send */
+		cur_rx;		/* current receive buffer */
+	int	lastload_dest,	/* can last loaded packet be acked? */
+		lasttrans_dest;	/* can last TX'd packet be acked? */
+	int	timed_out;	/* need to process TX timeout and drop packet */
+	unsigned long last_timeout;	/* time of last reported timeout */
+	char *card_name;	/* card ident string */
+	int card_flags;		/* special card features */
+
+	/* On preemptive and SMP a lock is needed */
+	spinlock_t lock;
+
+	struct led_trigger *tx_led_trig;
+	char tx_led_trig_name[ARCNET_LED_NAME_SZ];
+	struct led_trigger *recon_led_trig;
+	char recon_led_trig_name[ARCNET_LED_NAME_SZ];
+
+	struct timer_list	timer;
+
+	struct net_device *dev;
+	int reply_status;
+	struct work_struct reply_work;
+
+	/*
+	 * Buffer management: an ARCnet card has 4 x 512-byte buffers, each of
+	 * which can be used for either sending or receiving.  The new dynamic
+	 * buffer management routines use a simple circular queue of available
+	 * buffers, and take them as they're needed.  This way, we simplify
+	 * situations in which we (for example) want to pre-load a transmit
+	 * buffer, or start receiving while we copy a received packet to
+	 * memory.
+	 *
+	 * The rules: only the interrupt handler is allowed to _add_ buffers to
+	 * the queue; thus, this doesn't require a lock.  Both the interrupt
+	 * handler and the transmit function will want to _remove_ buffers, so
+	 * we need to handle the situation where they try to do it at the same
+	 * time.
+	 *
+	 * If next_buf == first_free_buf, the queue is empty.  Since there are
+	 * only four possible buffers, the queue should never be full.
+	 */
+	atomic_t buf_lock;
+	int buf_queue[5];
+	int next_buf, first_free_buf;
+
+	/* network "reconfiguration" handling */
+	unsigned long first_recon; /* time of "first" RECON message to count */
+	unsigned long last_recon;  /* time of most recent RECON */
+	int num_recons;		/* number of RECONs between first and last. */
+	int network_down;	/* do we think the network is down? */
+
+	int excnak_pending;    /* We just got an excessive nak interrupt */
+
+	/* RESET flag handling */
+	int reset_in_progress;
+	struct work_struct reset_work;
+
+	struct {
+		uint16_t sequence;	/* sequence number (incs with each packet) */
+		__be16 aborted_seq;
+
+		struct Incoming incoming[256];	/* one from each address */
+	} rfc1201;
+
+	/* really only used by rfc1201, but we'll pretend it's not */
+	struct Outgoing outgoing;	/* packet currently being sent */
+
+	/* hardware-specific functions */
+	struct {
+		struct module *owner;
+		void (*command)(struct net_device *dev, int cmd);
+		int (*status)(struct net_device *dev);
+		void (*intmask)(struct net_device *dev, int mask);
+		int (*reset)(struct net_device *dev, int really_reset);
+		void (*open)(struct net_device *dev);
+		void (*close)(struct net_device *dev);
+		void (*datatrigger) (struct net_device * dev, int enable);
+		void (*recontrigger) (struct net_device * dev, int enable);
+
+		void (*copy_to_card)(struct net_device *dev, int bufnum,
+				     int offset, void *buf, int count);
+		void (*copy_from_card)(struct net_device *dev, int bufnum,
+				       int offset, void *buf, int count);
+	} hw;
+
+	void __iomem *mem_start;	/* pointer to ioremap'ed MMIO */
+};
+
+enum arcnet_led_event {
+	ARCNET_LED_EVENT_RECON,
+	ARCNET_LED_EVENT_OPEN,
+	ARCNET_LED_EVENT_STOP,
+	ARCNET_LED_EVENT_TX,
+};
+
+void arcnet_led_event(struct net_device *netdev, enum arcnet_led_event event);
+void devm_arcnet_led_init(struct net_device *netdev, int index, int subid);
+
+#if ARCNET_DEBUG_MAX & D_SKB
+void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc);
+#else
+static inline
+void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc)
+{
+}
+#endif
+
+void arcnet_unregister_proto(struct ArcProto *proto);
+irqreturn_t arcnet_interrupt(int irq, void *dev_id);
+
+struct net_device *alloc_arcdev(const char *name);
+void free_arcdev(struct net_device *dev);
+
+int arcnet_open(struct net_device *dev);
+int arcnet_close(struct net_device *dev);
+netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
+			       struct net_device *dev);
+void arcnet_timeout(struct net_device *dev, unsigned int txqueue);
+
+static inline void arcnet_set_addr(struct net_device *dev, u8 addr)
+{
+	dev_addr_set(dev, &addr);
+}
+
+#endif				/* __KERNEL__ */
+#endif				/* _LINUX_ARCDEVICE_H */