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, 356 insertions, 0 deletions

diff --git a/drivers/soc/aspeed/aspeed-lpc-ctrl.c b/drivers/soc/aspeed/aspeed-lpc-ctrl.c
new file mode 100644
index 000000000..4d8574cac
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-lpc-ctrl.c
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2017 IBM Corporation
+ */
+
+#include <linux/clk.h>
+#include <linux/log2.h>
+#include <linux/mfd/syscon.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/regmap.h>
+
+#include <linux/aspeed-lpc-ctrl.h>
+
+#define DEVICE_NAME	"aspeed-lpc-ctrl"
+
+#define HICR5 0x80
+#define HICR5_ENL2H	BIT(8)
+#define HICR5_ENFWH	BIT(10)
+
+#define HICR6 0x84
+#define SW_FWH2AHB	BIT(17)
+
+#define HICR7 0x88
+#define HICR8 0x8c
+
+struct aspeed_lpc_ctrl {
+	struct miscdevice	miscdev;
+	struct regmap		*regmap;
+	struct clk		*clk;
+	phys_addr_t		mem_base;
+	resource_size_t		mem_size;
+	u32			pnor_size;
+	u32			pnor_base;
+	bool			fwh2ahb;
+	struct regmap		*scu;
+};
+
+static struct aspeed_lpc_ctrl *file_aspeed_lpc_ctrl(struct file *file)
+{
+	return container_of(file->private_data, struct aspeed_lpc_ctrl,
+			miscdev);
+}
+
+static int aspeed_lpc_ctrl_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
+	unsigned long vsize = vma->vm_end - vma->vm_start;
+	pgprot_t prot = vma->vm_page_prot;
+
+	if (vma->vm_pgoff + vma_pages(vma) > lpc_ctrl->mem_size >> PAGE_SHIFT)
+		return -EINVAL;
+
+	/* ast2400/2500 AHB accesses are not cache coherent */
+	prot = pgprot_noncached(prot);
+
+	if (remap_pfn_range(vma, vma->vm_start,
+		(lpc_ctrl->mem_base >> PAGE_SHIFT) + vma->vm_pgoff,
+		vsize, prot))
+		return -EAGAIN;
+
+	return 0;
+}
+
+static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
+		unsigned long param)
+{
+	struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
+	struct device *dev = file->private_data;
+	void __user *p = (void __user *)param;
+	struct aspeed_lpc_ctrl_mapping map;
+	u32 addr;
+	u32 size;
+	long rc;
+
+	if (copy_from_user(&map, p, sizeof(map)))
+		return -EFAULT;
+
+	if (map.flags != 0)
+		return -EINVAL;
+
+	switch (cmd) {
+	case ASPEED_LPC_CTRL_IOCTL_GET_SIZE:
+		/* The flash windows don't report their size */
+		if (map.window_type != ASPEED_LPC_CTRL_WINDOW_MEMORY)
+			return -EINVAL;
+
+		/* Support more than one window id in the future */
+		if (map.window_id != 0)
+			return -EINVAL;
+
+		/* If memory-region is not described in device tree */
+		if (!lpc_ctrl->mem_size) {
+			dev_dbg(dev, "Didn't find reserved memory\n");
+			return -ENXIO;
+		}
+
+		map.size = lpc_ctrl->mem_size;
+
+		return copy_to_user(p, &map, sizeof(map)) ? -EFAULT : 0;
+	case ASPEED_LPC_CTRL_IOCTL_MAP:
+
+		/*
+		 * The top half of HICR7 is the MSB of the BMC address of the
+		 * mapping.
+		 * The bottom half of HICR7 is the MSB of the HOST LPC
+		 * firmware space address of the mapping.
+		 *
+		 * The 1 bits in the top of half of HICR8 represent the bits
+		 * (in the requested address) that should be ignored and
+		 * replaced with those from the top half of HICR7.
+		 * The 1 bits in the bottom half of HICR8 represent the bits
+		 * (in the requested address) that should be kept and pass
+		 * into the BMC address space.
+		 */
+
+		/*
+		 * It doesn't make sense to talk about a size or offset with
+		 * low 16 bits set. Both HICR7 and HICR8 talk about the top 16
+		 * bits of addresses and sizes.
+		 */
+
+		if ((map.size & 0x0000ffff) || (map.offset & 0x0000ffff))
+			return -EINVAL;
+
+		/*
+		 * Because of the way the masks work in HICR8 offset has to
+		 * be a multiple of size.
+		 */
+		if (map.offset & (map.size - 1))
+			return -EINVAL;
+
+		if (map.window_type == ASPEED_LPC_CTRL_WINDOW_FLASH) {
+			if (!lpc_ctrl->pnor_size) {
+				dev_dbg(dev, "Didn't find host pnor flash\n");
+				return -ENXIO;
+			}
+			addr = lpc_ctrl->pnor_base;
+			size = lpc_ctrl->pnor_size;
+		} else if (map.window_type == ASPEED_LPC_CTRL_WINDOW_MEMORY) {
+			/* If memory-region is not described in device tree */
+			if (!lpc_ctrl->mem_size) {
+				dev_dbg(dev, "Didn't find reserved memory\n");
+				return -ENXIO;
+			}
+			addr = lpc_ctrl->mem_base;
+			size = lpc_ctrl->mem_size;
+		} else {
+			return -EINVAL;
+		}
+
+		/* Check overflow first! */
+		if (map.offset + map.size < map.offset ||
+			map.offset + map.size > size)
+			return -EINVAL;
+
+		if (map.size == 0 || map.size > size)
+			return -EINVAL;
+
+		addr += map.offset;
+
+		/*
+		 * addr (host lpc address) is safe regardless of values. This
+		 * simply changes the address the host has to request on its
+		 * side of the LPC bus. This cannot impact the hosts own
+		 * memory space by surprise as LPC specific accessors are
+		 * required. The only strange thing that could be done is
+		 * setting the lower 16 bits but the shift takes care of that.
+		 */
+
+		rc = regmap_write(lpc_ctrl->regmap, HICR7,
+				(addr | (map.addr >> 16)));
+		if (rc)
+			return rc;
+
+		rc = regmap_write(lpc_ctrl->regmap, HICR8,
+				(~(map.size - 1)) | ((map.size >> 16) - 1));
+		if (rc)
+			return rc;
+
+		/*
+		 * Switch to FWH2AHB mode, AST2600 only.
+		 */
+		if (lpc_ctrl->fwh2ahb) {
+			/*
+			 * Enable FWH2AHB in SCU debug control register 2. This
+			 * does not turn it on, but makes it available for it
+			 * to be configured in HICR6.
+			 */
+			regmap_update_bits(lpc_ctrl->scu, 0x0D8, BIT(2), 0);
+
+			/*
+			 * The other bits in this register are interrupt status bits
+			 * that are cleared by writing 1. As we don't want to clear
+			 * them, set only the bit of interest.
+			 */
+			regmap_write(lpc_ctrl->regmap, HICR6, SW_FWH2AHB);
+		}
+
+		/*
+		 * Enable LPC FHW cycles. This is required for the host to
+		 * access the regions specified.
+		 */
+		return regmap_update_bits(lpc_ctrl->regmap, HICR5,
+				HICR5_ENFWH | HICR5_ENL2H,
+				HICR5_ENFWH | HICR5_ENL2H);
+	}
+
+	return -EINVAL;
+}
+
+static const struct file_operations aspeed_lpc_ctrl_fops = {
+	.owner		= THIS_MODULE,
+	.mmap		= aspeed_lpc_ctrl_mmap,
+	.unlocked_ioctl	= aspeed_lpc_ctrl_ioctl,
+};
+
+static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
+{
+	struct aspeed_lpc_ctrl *lpc_ctrl;
+	struct device_node *node;
+	struct resource resm;
+	struct device *dev;
+	struct device_node *np;
+	int rc;
+
+	dev = &pdev->dev;
+
+	lpc_ctrl = devm_kzalloc(dev, sizeof(*lpc_ctrl), GFP_KERNEL);
+	if (!lpc_ctrl)
+		return -ENOMEM;
+
+	/* If flash is described in device tree then store */
+	node = of_parse_phandle(dev->of_node, "flash", 0);
+	if (!node) {
+		dev_dbg(dev, "Didn't find host pnor flash node\n");
+	} else {
+		rc = of_address_to_resource(node, 1, &resm);
+		of_node_put(node);
+		if (rc) {
+			dev_err(dev, "Couldn't address to resource for flash\n");
+			return rc;
+		}
+
+		lpc_ctrl->pnor_size = resource_size(&resm);
+		lpc_ctrl->pnor_base = resm.start;
+	}
+
+
+	dev_set_drvdata(&pdev->dev, lpc_ctrl);
+
+	/* If memory-region is described in device tree then store */
+	rc = of_reserved_mem_region_to_resource(dev->of_node, 0, &resm);
+	if (!rc) {
+		lpc_ctrl->mem_size = resource_size(&resm);
+		lpc_ctrl->mem_base = resm.start;
+
+		if (!is_power_of_2(lpc_ctrl->mem_size)) {
+			dev_err(dev, "Reserved memory size must be a power of 2, got %u\n",
+			       (unsigned int)lpc_ctrl->mem_size);
+			return -EINVAL;
+		}
+
+		if (!IS_ALIGNED(lpc_ctrl->mem_base, lpc_ctrl->mem_size)) {
+			dev_err(dev, "Reserved memory must be naturally aligned for size %u\n",
+			       (unsigned int)lpc_ctrl->mem_size);
+			return -EINVAL;
+		}
+	}
+
+	np = pdev->dev.parent->of_node;
+	if (!of_device_is_compatible(np, "aspeed,ast2400-lpc-v2") &&
+	    !of_device_is_compatible(np, "aspeed,ast2500-lpc-v2") &&
+	    !of_device_is_compatible(np, "aspeed,ast2600-lpc-v2")) {
+		dev_err(dev, "unsupported LPC device binding\n");
+		return -ENODEV;
+	}
+
+	lpc_ctrl->regmap = syscon_node_to_regmap(np);
+	if (IS_ERR(lpc_ctrl->regmap)) {
+		dev_err(dev, "Couldn't get regmap\n");
+		return -ENODEV;
+	}
+
+	if (of_device_is_compatible(dev->of_node, "aspeed,ast2600-lpc-ctrl")) {
+		lpc_ctrl->fwh2ahb = true;
+
+		lpc_ctrl->scu = syscon_regmap_lookup_by_compatible("aspeed,ast2600-scu");
+		if (IS_ERR(lpc_ctrl->scu)) {
+			dev_err(dev, "couldn't find scu\n");
+			return PTR_ERR(lpc_ctrl->scu);
+		}
+	}
+
+	lpc_ctrl->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(lpc_ctrl->clk))
+		return dev_err_probe(dev, PTR_ERR(lpc_ctrl->clk),
+				     "couldn't get clock\n");
+	rc = clk_prepare_enable(lpc_ctrl->clk);
+	if (rc) {
+		dev_err(dev, "couldn't enable clock\n");
+		return rc;
+	}
+
+	lpc_ctrl->miscdev.minor = MISC_DYNAMIC_MINOR;
+	lpc_ctrl->miscdev.name = DEVICE_NAME;
+	lpc_ctrl->miscdev.fops = &aspeed_lpc_ctrl_fops;
+	lpc_ctrl->miscdev.parent = dev;
+	rc = misc_register(&lpc_ctrl->miscdev);
+	if (rc) {
+		dev_err(dev, "Unable to register device\n");
+		goto err;
+	}
+
+	return 0;
+
+err:
+	clk_disable_unprepare(lpc_ctrl->clk);
+	return rc;
+}
+
+static void aspeed_lpc_ctrl_remove(struct platform_device *pdev)
+{
+	struct aspeed_lpc_ctrl *lpc_ctrl = dev_get_drvdata(&pdev->dev);
+
+	misc_deregister(&lpc_ctrl->miscdev);
+	clk_disable_unprepare(lpc_ctrl->clk);
+}
+
+static const struct of_device_id aspeed_lpc_ctrl_match[] = {
+	{ .compatible = "aspeed,ast2400-lpc-ctrl" },
+	{ .compatible = "aspeed,ast2500-lpc-ctrl" },
+	{ .compatible = "aspeed,ast2600-lpc-ctrl" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, aspeed_lpc_ctrl_match);
+
+static struct platform_driver aspeed_lpc_ctrl_driver = {
+	.driver = {
+		.name		= DEVICE_NAME,
+		.of_match_table = aspeed_lpc_ctrl_match,
+	},
+	.probe = aspeed_lpc_ctrl_probe,
+	.remove = aspeed_lpc_ctrl_remove,
+};
+
+module_platform_driver(aspeed_lpc_ctrl_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Cyril Bur <cyrilbur@gmail.com>");
+MODULE_DESCRIPTION("Control for ASPEED LPC HOST to BMC mappings");