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, 448 insertions, 0 deletions

diff --git a/drivers/clk/qcom/krait-cc.c b/drivers/clk/qcom/krait-cc.c
new file mode 100644
index 000000000..f29d6dd1f
--- /dev/null
+++ b/drivers/clk/qcom/krait-cc.c
@@ -0,0 +1,448 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018, The Linux Foundation. All rights reserved.
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+
+#include "clk-krait.h"
+
+enum {
+	cpu0_mux = 0,
+	cpu1_mux,
+	cpu2_mux,
+	cpu3_mux,
+	l2_mux,
+
+	clks_max,
+};
+
+static unsigned int sec_mux_map[] = {
+	2,
+	0,
+};
+
+static unsigned int pri_mux_map[] = {
+	1,
+	2,
+	0,
+};
+
+/*
+ * Notifier function for switching the muxes to safe parent
+ * while the hfpll is getting reprogrammed.
+ */
+static int krait_notifier_cb(struct notifier_block *nb,
+			     unsigned long event,
+			     void *data)
+{
+	int ret = 0;
+	struct krait_mux_clk *mux = container_of(nb, struct krait_mux_clk,
+						 clk_nb);
+	/* Switch to safe parent */
+	if (event == PRE_RATE_CHANGE) {
+		mux->old_index = krait_mux_clk_ops.get_parent(&mux->hw);
+		ret = krait_mux_clk_ops.set_parent(&mux->hw, mux->safe_sel);
+		mux->reparent = false;
+	/*
+	 * By the time POST_RATE_CHANGE notifier is called,
+	 * clk framework itself would have changed the parent for the new rate.
+	 * Only otherwise, put back to the old parent.
+	 */
+	} else if (event == POST_RATE_CHANGE) {
+		if (!mux->reparent)
+			ret = krait_mux_clk_ops.set_parent(&mux->hw,
+							   mux->old_index);
+	}
+
+	return notifier_from_errno(ret);
+}
+
+static int krait_notifier_register(struct device *dev, struct clk *clk,
+				   struct krait_mux_clk *mux)
+{
+	int ret = 0;
+
+	mux->clk_nb.notifier_call = krait_notifier_cb;
+	ret = devm_clk_notifier_register(dev, clk, &mux->clk_nb);
+	if (ret)
+		dev_err(dev, "failed to register clock notifier: %d\n", ret);
+
+	return ret;
+}
+
+static struct clk_hw *
+krait_add_div(struct device *dev, int id, const char *s, unsigned int offset)
+{
+	struct krait_div2_clk *div;
+	static struct clk_parent_data p_data[1];
+	struct clk_init_data init = {
+		.num_parents = ARRAY_SIZE(p_data),
+		.ops = &krait_div2_clk_ops,
+		.flags = CLK_SET_RATE_PARENT,
+	};
+	struct clk_hw *clk;
+	char *parent_name;
+	int cpu, ret;
+
+	div = devm_kzalloc(dev, sizeof(*div), GFP_KERNEL);
+	if (!div)
+		return ERR_PTR(-ENOMEM);
+
+	div->width = 2;
+	div->shift = 6;
+	div->lpl = id >= 0;
+	div->offset = offset;
+	div->hw.init = &init;
+
+	init.name = kasprintf(GFP_KERNEL, "hfpll%s_div", s);
+	if (!init.name)
+		return ERR_PTR(-ENOMEM);
+
+	init.parent_data = p_data;
+	parent_name = kasprintf(GFP_KERNEL, "hfpll%s", s);
+	if (!parent_name) {
+		clk = ERR_PTR(-ENOMEM);
+		goto err_parent_name;
+	}
+
+	p_data[0].fw_name = parent_name;
+	p_data[0].name = parent_name;
+
+	ret = devm_clk_hw_register(dev, &div->hw);
+	if (ret) {
+		clk = ERR_PTR(ret);
+		goto err_clk;
+	}
+
+	clk = &div->hw;
+
+	/* clk-krait ignore any rate change if mux is not flagged as enabled */
+	if (id < 0)
+		for_each_online_cpu(cpu)
+			clk_prepare_enable(div->hw.clk);
+	else
+		clk_prepare_enable(div->hw.clk);
+
+err_clk:
+	kfree(parent_name);
+err_parent_name:
+	kfree(init.name);
+
+	return clk;
+}
+
+static struct clk_hw *
+krait_add_sec_mux(struct device *dev, int id, const char *s,
+		  unsigned int offset, bool unique_aux)
+{
+	int cpu, ret;
+	struct krait_mux_clk *mux;
+	static struct clk_parent_data sec_mux_list[2] = {
+		{ .name = "qsb", .fw_name = "qsb" },
+		{},
+	};
+	struct clk_init_data init = {
+		.parent_data = sec_mux_list,
+		.num_parents = ARRAY_SIZE(sec_mux_list),
+		.ops = &krait_mux_clk_ops,
+		.flags = CLK_SET_RATE_PARENT,
+	};
+	struct clk_hw *clk;
+	char *parent_name;
+
+	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return ERR_PTR(-ENOMEM);
+
+	mux->offset = offset;
+	mux->lpl = id >= 0;
+	mux->mask = 0x3;
+	mux->shift = 2;
+	mux->parent_map = sec_mux_map;
+	mux->hw.init = &init;
+	mux->safe_sel = 0;
+
+	/* Checking for qcom,krait-cc-v1 or qcom,krait-cc-v2 is not
+	 * enough to limit this to apq/ipq8064. Directly check machine
+	 * compatible to correctly handle this errata.
+	 */
+	if (of_machine_is_compatible("qcom,ipq8064") ||
+	    of_machine_is_compatible("qcom,apq8064"))
+		mux->disable_sec_src_gating = true;
+
+	init.name = kasprintf(GFP_KERNEL, "krait%s_sec_mux", s);
+	if (!init.name)
+		return ERR_PTR(-ENOMEM);
+
+	if (unique_aux) {
+		parent_name = kasprintf(GFP_KERNEL, "acpu%s_aux", s);
+		if (!parent_name) {
+			clk = ERR_PTR(-ENOMEM);
+			goto err_aux;
+		}
+		sec_mux_list[1].fw_name = parent_name;
+		sec_mux_list[1].name = parent_name;
+	} else {
+		sec_mux_list[1].name = "apu_aux";
+	}
+
+	ret = devm_clk_hw_register(dev, &mux->hw);
+	if (ret) {
+		clk = ERR_PTR(ret);
+		goto err_clk;
+	}
+
+	clk = &mux->hw;
+
+	ret = krait_notifier_register(dev, mux->hw.clk, mux);
+	if (ret) {
+		clk = ERR_PTR(ret);
+		goto err_clk;
+	}
+
+	/* clk-krait ignore any rate change if mux is not flagged as enabled */
+	if (id < 0)
+		for_each_online_cpu(cpu)
+			clk_prepare_enable(mux->hw.clk);
+	else
+		clk_prepare_enable(mux->hw.clk);
+
+err_clk:
+	if (unique_aux)
+		kfree(parent_name);
+err_aux:
+	kfree(init.name);
+	return clk;
+}
+
+static struct clk_hw *
+krait_add_pri_mux(struct device *dev, struct clk_hw *hfpll_div, struct clk_hw *sec_mux,
+		  int id, const char *s, unsigned int offset)
+{
+	int ret;
+	struct krait_mux_clk *mux;
+	static struct clk_parent_data p_data[3];
+	struct clk_init_data init = {
+		.parent_data = p_data,
+		.num_parents = ARRAY_SIZE(p_data),
+		.ops = &krait_mux_clk_ops,
+		.flags = CLK_SET_RATE_PARENT,
+	};
+	struct clk_hw *clk;
+	char *hfpll_name;
+
+	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return ERR_PTR(-ENOMEM);
+
+	mux->mask = 0x3;
+	mux->shift = 0;
+	mux->offset = offset;
+	mux->lpl = id >= 0;
+	mux->parent_map = pri_mux_map;
+	mux->hw.init = &init;
+	mux->safe_sel = 2;
+
+	init.name = kasprintf(GFP_KERNEL, "krait%s_pri_mux", s);
+	if (!init.name)
+		return ERR_PTR(-ENOMEM);
+
+	hfpll_name = kasprintf(GFP_KERNEL, "hfpll%s", s);
+	if (!hfpll_name) {
+		clk = ERR_PTR(-ENOMEM);
+		goto err_hfpll;
+	}
+
+	p_data[0].fw_name = hfpll_name;
+	p_data[0].name = hfpll_name;
+
+	p_data[1].hw = hfpll_div;
+	p_data[2].hw = sec_mux;
+
+	ret = devm_clk_hw_register(dev, &mux->hw);
+	if (ret) {
+		clk = ERR_PTR(ret);
+		goto err_clk;
+	}
+
+	clk = &mux->hw;
+
+	ret = krait_notifier_register(dev, mux->hw.clk, mux);
+	if (ret)
+		clk = ERR_PTR(ret);
+
+err_clk:
+	kfree(hfpll_name);
+err_hfpll:
+	kfree(init.name);
+	return clk;
+}
+
+/* id < 0 for L2, otherwise id == physical CPU number */
+static struct clk_hw *krait_add_clks(struct device *dev, int id, bool unique_aux)
+{
+	struct clk_hw *hfpll_div, *sec_mux, *pri_mux;
+	unsigned int offset;
+	void *p = NULL;
+	const char *s;
+
+	if (id >= 0) {
+		offset = 0x4501 + (0x1000 * id);
+		s = p = kasprintf(GFP_KERNEL, "%d", id);
+		if (!s)
+			return ERR_PTR(-ENOMEM);
+	} else {
+		offset = 0x500;
+		s = "_l2";
+	}
+
+	hfpll_div = krait_add_div(dev, id, s, offset);
+	if (IS_ERR(hfpll_div)) {
+		pri_mux = hfpll_div;
+		goto err;
+	}
+
+	sec_mux = krait_add_sec_mux(dev, id, s, offset, unique_aux);
+	if (IS_ERR(sec_mux)) {
+		pri_mux = sec_mux;
+		goto err;
+	}
+
+	pri_mux = krait_add_pri_mux(dev, hfpll_div, sec_mux, id, s, offset);
+
+err:
+	kfree(p);
+	return pri_mux;
+}
+
+static struct clk *krait_of_get(struct of_phandle_args *clkspec, void *data)
+{
+	unsigned int idx = clkspec->args[0];
+	struct clk **clks = data;
+
+	if (idx >= clks_max) {
+		pr_err("%s: invalid clock index %d\n", __func__, idx);
+		return ERR_PTR(-EINVAL);
+	}
+
+	return clks[idx] ? : ERR_PTR(-ENODEV);
+}
+
+static const struct of_device_id krait_cc_match_table[] = {
+	{ .compatible = "qcom,krait-cc-v1", (void *)1UL },
+	{ .compatible = "qcom,krait-cc-v2" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, krait_cc_match_table);
+
+static int krait_cc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	unsigned long cur_rate, aux_rate;
+	int cpu;
+	struct clk_hw *mux, *l2_pri_mux;
+	struct clk *clk, **clks;
+	bool unique_aux = !!device_get_match_data(dev);
+
+	/* Rate is 1 because 0 causes problems for __clk_mux_determine_rate */
+	clk = clk_register_fixed_rate(dev, "qsb", NULL, 0, 1);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	if (!unique_aux) {
+		clk = clk_register_fixed_factor(dev, "acpu_aux",
+						"gpll0_vote", 0, 1, 2);
+		if (IS_ERR(clk))
+			return PTR_ERR(clk);
+	}
+
+	/* Krait configurations have at most 4 CPUs and one L2 */
+	clks = devm_kcalloc(dev, clks_max, sizeof(*clks), GFP_KERNEL);
+	if (!clks)
+		return -ENOMEM;
+
+	for_each_possible_cpu(cpu) {
+		mux = krait_add_clks(dev, cpu, unique_aux);
+		if (IS_ERR(mux))
+			return PTR_ERR(mux);
+		clks[cpu] = mux->clk;
+	}
+
+	l2_pri_mux = krait_add_clks(dev, -1, unique_aux);
+	if (IS_ERR(l2_pri_mux))
+		return PTR_ERR(l2_pri_mux);
+	clks[l2_mux] = l2_pri_mux->clk;
+
+	/*
+	 * We don't want the CPU or L2 clocks to be turned off at late init
+	 * if CPUFREQ or HOTPLUG configs are disabled. So, bump up the
+	 * refcount of these clocks. Any cpufreq/hotplug manager can assume
+	 * that the clocks have already been prepared and enabled by the time
+	 * they take over.
+	 */
+	for_each_online_cpu(cpu) {
+		clk_prepare_enable(clks[l2_mux]);
+		WARN(clk_prepare_enable(clks[cpu]),
+		     "Unable to turn on CPU%d clock", cpu);
+	}
+
+	/*
+	 * Force reinit of HFPLLs and muxes to overwrite any potential
+	 * incorrect configuration of HFPLLs and muxes by the bootloader.
+	 * While at it, also make sure the cores are running at known rates
+	 * and print the current rate.
+	 *
+	 * The clocks are set to aux clock rate first to make sure the
+	 * secondary mux is not sourcing off of QSB. The rate is then set to
+	 * two different rates to force a HFPLL reinit under all
+	 * circumstances.
+	 */
+	cur_rate = clk_get_rate(clks[l2_mux]);
+	aux_rate = 384000000;
+	if (cur_rate < aux_rate) {
+		pr_info("L2 @ Undefined rate. Forcing new rate.\n");
+		cur_rate = aux_rate;
+	}
+	clk_set_rate(clks[l2_mux], aux_rate);
+	clk_set_rate(clks[l2_mux], 2);
+	clk_set_rate(clks[l2_mux], cur_rate);
+	pr_info("L2 @ %lu KHz\n", clk_get_rate(clks[l2_mux]) / 1000);
+	for_each_possible_cpu(cpu) {
+		clk = clks[cpu];
+		cur_rate = clk_get_rate(clk);
+		if (cur_rate < aux_rate) {
+			pr_info("CPU%d @ Undefined rate. Forcing new rate.\n", cpu);
+			cur_rate = aux_rate;
+		}
+
+		clk_set_rate(clk, aux_rate);
+		clk_set_rate(clk, 2);
+		clk_set_rate(clk, cur_rate);
+		pr_info("CPU%d @ %lu KHz\n", cpu, clk_get_rate(clk) / 1000);
+	}
+
+	of_clk_add_provider(dev->of_node, krait_of_get, clks);
+
+	return 0;
+}
+
+static struct platform_driver krait_cc_driver = {
+	.probe = krait_cc_probe,
+	.driver = {
+		.name = "krait-cc",
+		.of_match_table = krait_cc_match_table,
+	},
+};
+module_platform_driver(krait_cc_driver);
+
+MODULE_DESCRIPTION("Krait CPU Clock Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:krait-cc");