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

3 files changed, 227 insertions, 0 deletions

diff --git a/include/soc/arc/arc_aux.h b/include/soc/arc/arc_aux.h
new file mode 100644
index 000000000..9c2eff614
--- /dev/null
+++ b/include/soc/arc/arc_aux.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2016-2017 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#ifndef __SOC_ARC_AUX_H__
+#define __SOC_ARC_AUX_H__
+
+#ifdef CONFIG_ARC
+
+#define read_aux_reg(r)		__builtin_arc_lr(r)
+
+/* gcc builtin sr needs reg param to be long immediate */
+#define write_aux_reg(r, v)	__builtin_arc_sr((unsigned int)(v), r)
+
+#else	/* !CONFIG_ARC */
+
+static inline int read_aux_reg(u32 r)
+{
+	return 0;
+}
+
+/*
+ * function helps elide unused variable warning
+ * see: https://lists.infradead.org/pipermail/linux-snps-arc/2016-November/001748.html
+ */
+static inline void write_aux_reg(u32 r, u32 v)
+{
+	;
+}
+
+#endif
+
+#define READ_BCR(reg, into)				\
+{							\
+	unsigned int tmp;				\
+	tmp = read_aux_reg(reg);			\
+	if (sizeof(tmp) == sizeof(into)) {		\
+		into = *((typeof(into) *)&tmp);		\
+	} else {					\
+		extern void bogus_undefined(void);	\
+		bogus_undefined();			\
+	}						\
+}
+
+#define WRITE_AUX(reg, into)				\
+{							\
+	unsigned int tmp;				\
+	if (sizeof(tmp) == sizeof(into)) {		\
+		tmp = (*(unsigned int *)&(into));	\
+		write_aux_reg(reg, tmp);		\
+	} else  {					\
+		extern void bogus_undefined(void);	\
+		bogus_undefined();			\
+	}						\
+}
+
+
+#endif
diff --git a/include/soc/arc/mcip.h b/include/soc/arc/mcip.h
new file mode 100644
index 000000000..a78dacd14
--- /dev/null
+++ b/include/soc/arc/mcip.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ARConnect IP Support (Multi core enabler: Cross core IPI, RTC ...)
+ *
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#ifndef __SOC_ARC_MCIP_H
+#define __SOC_ARC_MCIP_H
+
+#include <soc/arc/arc_aux.h>
+
+#define ARC_REG_MCIP_BCR	0x0d0
+#define ARC_REG_MCIP_IDU_BCR	0x0D5
+#define ARC_REG_GFRC_BUILD	0x0D6
+#define ARC_REG_MCIP_CMD	0x600
+#define ARC_REG_MCIP_WDATA	0x601
+#define ARC_REG_MCIP_READBACK	0x602
+
+struct mcip_cmd {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	unsigned int pad:8, param:16, cmd:8;
+#else
+	unsigned int cmd:8, param:16, pad:8;
+#endif
+
+#define CMD_INTRPT_GENERATE_IRQ		0x01
+#define CMD_INTRPT_GENERATE_ACK		0x02
+#define CMD_INTRPT_READ_STATUS		0x03
+#define CMD_INTRPT_CHECK_SOURCE		0x04
+
+/* Semaphore Commands */
+#define CMD_SEMA_CLAIM_AND_READ		0x11
+#define CMD_SEMA_RELEASE		0x12
+
+#define CMD_DEBUG_SET_MASK		0x34
+#define CMD_DEBUG_READ_MASK		0x35
+#define CMD_DEBUG_SET_SELECT		0x36
+#define CMD_DEBUG_READ_SELECT		0x37
+
+#define CMD_GFRC_READ_LO		0x42
+#define CMD_GFRC_READ_HI		0x43
+#define CMD_GFRC_SET_CORE		0x47
+#define CMD_GFRC_READ_CORE		0x48
+
+#define CMD_IDU_ENABLE			0x71
+#define CMD_IDU_DISABLE			0x72
+#define CMD_IDU_SET_MODE		0x74
+#define CMD_IDU_READ_MODE		0x75
+#define CMD_IDU_SET_DEST		0x76
+#define CMD_IDU_ACK_CIRQ		0x79
+#define CMD_IDU_SET_MASK		0x7C
+
+#define IDU_M_TRIG_LEVEL		0x0
+#define IDU_M_TRIG_EDGE			0x1
+
+#define IDU_M_DISTRI_RR			0x0
+#define IDU_M_DISTRI_DEST		0x2
+};
+
+struct mcip_bcr {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		unsigned int pad4:6, pw_dom:1, pad3:1,
+			     idu:1, pad2:1, num_cores:6,
+			     pad:1,  gfrc:1, dbg:1, pw:1,
+			     msg:1, sem:1, ipi:1, slv:1,
+			     ver:8;
+#else
+		unsigned int ver:8,
+			     slv:1, ipi:1, sem:1, msg:1,
+			     pw:1, dbg:1, gfrc:1, pad:1,
+			     num_cores:6, pad2:1, idu:1,
+			     pad3:1, pw_dom:1, pad4:6;
+#endif
+};
+
+struct mcip_idu_bcr {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	unsigned int pad:21, cirqnum:3, ver:8;
+#else
+	unsigned int ver:8, cirqnum:3, pad:21;
+#endif
+};
+
+
+/*
+ * Build register for IDU contains not an actual number of supported common
+ * interrupts but an exponent of 2 which must be multiplied by 4 to
+ * get a number of supported common interrupts.
+ */
+#define mcip_idu_bcr_to_nr_irqs(bcr) (4 * (1 << (bcr).cirqnum))
+
+/*
+ * MCIP programming model
+ *
+ * - Simple commands write {cmd:8,param:16} to MCIP_CMD aux reg
+ *   (param could be irq, common_irq, core_id ...)
+ * - More involved commands setup MCIP_WDATA with cmd specific data
+ *   before invoking the simple command
+ */
+static inline void __mcip_cmd(unsigned int cmd, unsigned int param)
+{
+	struct mcip_cmd buf;
+
+	buf.pad = 0;
+	buf.cmd = cmd;
+	buf.param = param;
+
+	WRITE_AUX(ARC_REG_MCIP_CMD, buf);
+}
+
+/*
+ * Setup additional data for a cmd
+ * Callers need to lock to ensure atomicity
+ */
+static inline void __mcip_cmd_data(unsigned int cmd, unsigned int param,
+				   unsigned int data)
+{
+	write_aux_reg(ARC_REG_MCIP_WDATA, data);
+
+	__mcip_cmd(cmd, param);
+}
+
+/*
+ * Read MCIP register
+ */
+static inline unsigned int __mcip_cmd_read(unsigned int cmd, unsigned int param)
+{
+	__mcip_cmd(cmd, param);
+	return read_aux_reg(ARC_REG_MCIP_READBACK);
+}
+
+#endif
diff --git a/include/soc/arc/timers.h b/include/soc/arc/timers.h
new file mode 100644
index 000000000..51a741662
--- /dev/null
+++ b/include/soc/arc/timers.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2016-17 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#ifndef __SOC_ARC_TIMERS_H
+#define __SOC_ARC_TIMERS_H
+
+#include <soc/arc/arc_aux.h>
+
+/* Timer related Aux registers */
+#define ARC_REG_TIMER0_LIMIT	0x23	/* timer 0 limit */
+#define ARC_REG_TIMER0_CTRL	0x22	/* timer 0 control */
+#define ARC_REG_TIMER0_CNT	0x21	/* timer 0 count */
+#define ARC_REG_TIMER1_LIMIT	0x102	/* timer 1 limit */
+#define ARC_REG_TIMER1_CTRL	0x101	/* timer 1 control */
+#define ARC_REG_TIMER1_CNT	0x100	/* timer 1 count */
+
+/* CTRL reg bits */
+#define ARC_TIMER_CTRL_IE	(1 << 0) /* Interrupt when Count reaches limit */
+#define ARC_TIMER_CTRL_NH	(1 << 1) /* Count only when CPU NOT halted */
+
+#define ARC_TIMERN_MAX		0xFFFFFFFF
+
+#define ARC_REG_TIMERS_BCR	0x75
+
+struct bcr_timer {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	unsigned int pad2:15, rtsc:1, pad1:5, rtc:1, t1:1, t0:1, ver:8;
+#else
+	unsigned int ver:8, t0:1, t1:1, rtc:1, pad1:5, rtsc:1, pad2:15;
+#endif
+};
+
+#endif