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, 185 insertions, 0 deletions

diff --git a/arch/arm/mach-versatile/versatile.c b/arch/arm/mach-versatile/versatile.c
new file mode 100644
index 000000000..581c97dc4
--- /dev/null
+++ b/arch/arm/mach-versatile/versatile.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Versatile board support using the device tree
+ *
+ *  Copyright (C) 2010 Secret Lab Technologies Ltd.
+ *  Copyright (C) 2009 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *  Copyright (C) 2004 ARM Limited
+ *  Copyright (C) 2000 Deep Blue Solutions Ltd
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/amba/bus.h>
+#include <linux/amba/mmci.h>
+#include <asm/mach-types.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+/* macro to get at MMIO space when running virtually */
+#define IO_ADDRESS(x)		(((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
+#define __io_address(n)		((void __iomem __force *)IO_ADDRESS(n))
+
+/*
+ * ------------------------------------------------------------------------
+ *  Versatile Registers
+ * ------------------------------------------------------------------------
+ */
+#define VERSATILE_SYS_PCICTL_OFFSET           0x44
+#define VERSATILE_SYS_MCI_OFFSET              0x48
+
+/*
+ * VERSATILE peripheral addresses
+ */
+#define VERSATILE_MMCI0_BASE           0x10005000	/* MMC interface */
+#define VERSATILE_MMCI1_BASE           0x1000B000	/* MMC Interface */
+#define VERSATILE_SCTL_BASE            0x101E0000	/* System controller */
+
+/*
+ * System controller bit assignment
+ */
+#define VERSATILE_REFCLK	0
+#define VERSATILE_TIMCLK	1
+
+#define VERSATILE_TIMER1_EnSel	15
+#define VERSATILE_TIMER2_EnSel	17
+#define VERSATILE_TIMER3_EnSel	19
+#define VERSATILE_TIMER4_EnSel	21
+
+static void __iomem *versatile_sys_base;
+
+static unsigned int mmc_status(struct device *dev)
+{
+	struct amba_device *adev = container_of(dev, struct amba_device, dev);
+	u32 mask;
+
+	if (adev->res.start == VERSATILE_MMCI0_BASE)
+		mask = 1;
+	else
+		mask = 2;
+
+	return readl(versatile_sys_base + VERSATILE_SYS_MCI_OFFSET) & mask;
+}
+
+static struct mmci_platform_data mmc0_plat_data = {
+	.ocr_mask	= MMC_VDD_32_33|MMC_VDD_33_34,
+	.status		= mmc_status,
+};
+
+static struct mmci_platform_data mmc1_plat_data = {
+	.ocr_mask	= MMC_VDD_32_33|MMC_VDD_33_34,
+	.status		= mmc_status,
+};
+
+/*
+ * Lookup table for attaching a specific name and platform_data pointer to
+ * devices as they get created by of_platform_populate().  Ideally this table
+ * would not exist, but the current clock implementation depends on some devices
+ * having a specific name.
+ */
+struct of_dev_auxdata versatile_auxdata_lookup[] __initdata = {
+	OF_DEV_AUXDATA("arm,primecell", VERSATILE_MMCI0_BASE, "fpga:05", &mmc0_plat_data),
+	OF_DEV_AUXDATA("arm,primecell", VERSATILE_MMCI1_BASE, "fpga:0b", &mmc1_plat_data),
+	{}
+};
+
+static struct map_desc versatile_io_desc[] __initdata __maybe_unused = {
+	{
+		.virtual	=  IO_ADDRESS(VERSATILE_SCTL_BASE),
+		.pfn		= __phys_to_pfn(VERSATILE_SCTL_BASE),
+		.length		= SZ_4K * 9,
+		.type		= MT_DEVICE
+	}
+};
+
+static void __init versatile_map_io(void)
+{
+	debug_ll_io_init();
+	iotable_init(versatile_io_desc, ARRAY_SIZE(versatile_io_desc));
+}
+
+static void __init versatile_init_early(void)
+{
+	u32 val;
+
+	/*
+	 * set clock frequency:
+	 *	VERSATILE_REFCLK is 32KHz
+	 *	VERSATILE_TIMCLK is 1MHz
+	 */
+	val = readl(__io_address(VERSATILE_SCTL_BASE));
+	writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
+	       (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) |
+	       (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
+	       (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
+	       __io_address(VERSATILE_SCTL_BASE));
+}
+
+static void __init versatile_dt_pci_init(void)
+{
+	u32 val;
+	struct device_node *np;
+	struct property *newprop;
+
+	np = of_find_compatible_node(NULL, NULL, "arm,versatile-pci");
+	if (!np)
+		return;
+
+	/* Check if PCI backplane is detected */
+	val = readl(versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
+	if (val & 1) {
+		/*
+		 * Enable PCI accesses. Note that the documentation is
+		 * inconsistent whether or not this is needed, but the old
+		 * driver had it so we will keep it.
+		 */
+		writel(1, versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
+		goto out_put_node;
+	}
+
+	newprop = kzalloc_obj(*newprop);
+	if (!newprop)
+		goto out_put_node;
+
+	newprop->name = kstrdup("status", GFP_KERNEL);
+	newprop->value = kstrdup("disabled", GFP_KERNEL);
+	newprop->length = sizeof("disabled");
+	of_update_property(np, newprop);
+
+	pr_info("Not plugged into PCI backplane!\n");
+
+out_put_node:
+	of_node_put(np);
+}
+
+static void __init versatile_dt_init(void)
+{
+	struct device_node *np;
+
+	np = of_find_compatible_node(NULL, NULL, "arm,core-module-versatile");
+	if (np)
+		versatile_sys_base = of_iomap(np, 0);
+	WARN_ON(!versatile_sys_base);
+
+	versatile_dt_pci_init();
+
+	of_platform_default_populate(NULL, versatile_auxdata_lookup, NULL);
+}
+
+static const char *const versatile_dt_match[] __initconst = {
+	"arm,versatile-ab",
+	"arm,versatile-pb",
+	NULL,
+};
+
+DT_MACHINE_START(VERSATILE_PB, "ARM-Versatile (Device Tree Support)")
+	.map_io		= versatile_map_io,
+	.init_early	= versatile_init_early,
+	.init_machine	= versatile_dt_init,
+	.dt_compat	= versatile_dt_match,
+MACHINE_END