ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 273 insertions, 0 deletions

diff --git a/sound/soc/codecs/rt715-sdca-sdw.c b/sound/soc/codecs/rt715-sdca-sdw.c
new file mode 100644
index 000000000..1b183b21a
--- /dev/null
+++ b/sound/soc/codecs/rt715-sdca-sdw.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// rt715-sdca-sdw.c -- rt715 ALSA SoC audio driver
+//
+// Copyright(c) 2020 Realtek Semiconductor Corp.
+//
+//
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/soundwire/sdw.h>
+#include <linux/soundwire/sdw_type.h>
+#include <linux/soundwire/sdw_registers.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <sound/soc.h>
+#include "rt715-sdca.h"
+#include "rt715-sdca-sdw.h"
+
+static bool rt715_sdca_readable_register(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case 0x201a ... 0x2027:
+	case 0x2029 ... 0x202a:
+	case 0x202d ... 0x2034:
+	case 0x2200 ... 0x2204:
+	case 0x2206 ... 0x2212:
+	case 0x2230 ... 0x2239:
+	case 0x2f5b:
+	case SDW_SDCA_CTL(FUN_MIC_ARRAY, RT715_SDCA_SMPU_TRIG_ST_EN,
+		RT715_SDCA_SMPU_TRIG_ST_CTRL, CH_00):
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool rt715_sdca_volatile_register(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case 0x201b:
+	case 0x201c:
+	case 0x201d:
+	case 0x201f:
+	case 0x2021:
+	case 0x2023:
+	case 0x2230:
+	case 0x202d ... 0x202f: /* BRA */
+	case 0x2200 ... 0x2212: /* i2c debug */
+	case 0x2f07:
+	case 0x2f1b ... 0x2f1e:
+	case 0x2f30 ... 0x2f34:
+	case 0x2f50 ... 0x2f51:
+	case 0x2f53 ... 0x2f59:
+	case 0x2f5c ... 0x2f5f:
+	case SDW_SDCA_CTL(FUN_MIC_ARRAY, RT715_SDCA_SMPU_TRIG_ST_EN,
+		RT715_SDCA_SMPU_TRIG_ST_CTRL, CH_00): /* VAD Searching status */
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool rt715_sdca_mbq_readable_register(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case 0x2000000:
+	case 0x200002b:
+	case 0x2000036:
+	case 0x2000037:
+	case 0x2000039:
+	case 0x2000044:
+	case 0x6100000:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool rt715_sdca_mbq_volatile_register(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case 0x2000000:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config rt715_sdca_regmap = {
+	.reg_bits = 32,
+	.val_bits = 8,
+	.readable_reg = rt715_sdca_readable_register,
+	.volatile_reg = rt715_sdca_volatile_register,
+	.max_register = 0x43ffffff,
+	.reg_defaults = rt715_reg_defaults_sdca,
+	.num_reg_defaults = ARRAY_SIZE(rt715_reg_defaults_sdca),
+	.cache_type = REGCACHE_MAPLE,
+	.use_single_read = true,
+	.use_single_write = true,
+};
+
+static const struct regmap_config rt715_sdca_mbq_regmap = {
+	.name = "sdw-mbq",
+	.reg_bits = 32,
+	.val_bits = 16,
+	.readable_reg = rt715_sdca_mbq_readable_register,
+	.volatile_reg = rt715_sdca_mbq_volatile_register,
+	.max_register = 0x43ffffff,
+	.reg_defaults = rt715_mbq_reg_defaults_sdca,
+	.num_reg_defaults = ARRAY_SIZE(rt715_mbq_reg_defaults_sdca),
+	.cache_type = REGCACHE_MAPLE,
+	.use_single_read = true,
+	.use_single_write = true,
+};
+
+static int rt715_sdca_update_status(struct sdw_slave *slave,
+				enum sdw_slave_status status)
+{
+	struct rt715_sdca_priv *rt715 = dev_get_drvdata(&slave->dev);
+
+	/*
+	 * Perform initialization only if slave status is present and
+	 * hw_init flag is false
+	 */
+	if (rt715->hw_init || status != SDW_SLAVE_ATTACHED)
+		return 0;
+
+	/* perform I/O transfers required for Slave initialization */
+	return rt715_sdca_io_init(&slave->dev, slave);
+}
+
+static int rt715_sdca_read_prop(struct sdw_slave *slave)
+{
+	struct sdw_slave_prop *prop = &slave->prop;
+	int nval, i;
+	u32 bit;
+	unsigned long addr;
+	struct sdw_dpn_prop *dpn;
+
+	prop->paging_support = true;
+
+	/* first we need to allocate memory for set bits in port lists */
+	prop->source_ports = 0x50;/* BITMAP: 01010000 */
+	prop->sink_ports = 0x0;	/* BITMAP:  00000000 */
+
+	nval = hweight32(prop->source_ports);
+	prop->src_dpn_prop = devm_kcalloc(&slave->dev, nval,
+					sizeof(*prop->src_dpn_prop),
+					GFP_KERNEL);
+	if (!prop->src_dpn_prop)
+		return -ENOMEM;
+
+	dpn = prop->src_dpn_prop;
+	i = 0;
+	addr = prop->source_ports;
+	for_each_set_bit(bit, &addr, 32) {
+		dpn[i].num = bit;
+		dpn[i].simple_ch_prep_sm = true;
+		dpn[i].ch_prep_timeout = 10;
+		i++;
+	}
+
+	/* set the timeout values */
+	prop->clk_stop_timeout = 200;
+
+	return 0;
+}
+
+static const struct sdw_slave_ops rt715_sdca_slave_ops = {
+	.read_prop = rt715_sdca_read_prop,
+	.update_status = rt715_sdca_update_status,
+};
+
+static int rt715_sdca_sdw_probe(struct sdw_slave *slave,
+			   const struct sdw_device_id *id)
+{
+	struct regmap *mbq_regmap, *regmap;
+
+	/* Regmap Initialization */
+	mbq_regmap = devm_regmap_init_sdw_mbq(slave, &rt715_sdca_mbq_regmap);
+	if (IS_ERR(mbq_regmap))
+		return PTR_ERR(mbq_regmap);
+
+	regmap = devm_regmap_init_sdw(slave, &rt715_sdca_regmap);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	return rt715_sdca_init(&slave->dev, mbq_regmap, regmap, slave);
+}
+
+static void rt715_sdca_sdw_remove(struct sdw_slave *slave)
+{
+	pm_runtime_disable(&slave->dev);
+}
+
+static const struct sdw_device_id rt715_sdca_id[] = {
+	SDW_SLAVE_ENTRY_EXT(0x025d, 0x715, 0x3, 0x1, 0),
+	SDW_SLAVE_ENTRY_EXT(0x025d, 0x714, 0x3, 0x1, 0),
+	{},
+};
+MODULE_DEVICE_TABLE(sdw, rt715_sdca_id);
+
+static int rt715_dev_suspend(struct device *dev)
+{
+	struct rt715_sdca_priv *rt715 = dev_get_drvdata(dev);
+
+	if (!rt715->hw_init)
+		return 0;
+
+	regcache_cache_only(rt715->regmap, true);
+	regcache_mark_dirty(rt715->regmap);
+	regcache_cache_only(rt715->mbq_regmap, true);
+	regcache_mark_dirty(rt715->mbq_regmap);
+
+	return 0;
+}
+
+#define RT715_PROBE_TIMEOUT 5000
+
+static int rt715_dev_resume(struct device *dev)
+{
+	struct sdw_slave *slave = dev_to_sdw_dev(dev);
+	struct rt715_sdca_priv *rt715 = dev_get_drvdata(dev);
+	int ret;
+
+	if (!rt715->first_hw_init)
+		return 0;
+
+	ret = sdw_slave_wait_for_init(slave, RT715_PROBE_TIMEOUT);
+	if (ret) {
+		sdw_show_ping_status(slave->bus, true);
+		return ret;
+	}
+
+	regcache_cache_only(rt715->regmap, false);
+	regcache_sync_region(rt715->regmap,
+		SDW_SDCA_CTL(FUN_JACK_CODEC, RT715_SDCA_ST_EN, RT715_SDCA_ST_CTRL,
+			CH_00),
+		SDW_SDCA_CTL(FUN_MIC_ARRAY, RT715_SDCA_SMPU_TRIG_ST_EN,
+			RT715_SDCA_SMPU_TRIG_ST_CTRL, CH_00));
+	regcache_cache_only(rt715->mbq_regmap, false);
+	regcache_sync_region(rt715->mbq_regmap, 0x2000000, 0x61020ff);
+	regcache_sync_region(rt715->mbq_regmap,
+		SDW_SDCA_CTL(FUN_JACK_CODEC, RT715_SDCA_ST_EN, RT715_SDCA_ST_CTRL,
+			CH_00),
+		SDW_SDCA_CTL(FUN_MIC_ARRAY, RT715_SDCA_SMPU_TRIG_ST_EN,
+			RT715_SDCA_SMPU_TRIG_ST_CTRL, CH_00));
+
+	return 0;
+}
+
+static const struct dev_pm_ops rt715_pm = {
+	SYSTEM_SLEEP_PM_OPS(rt715_dev_suspend, rt715_dev_resume)
+	RUNTIME_PM_OPS(rt715_dev_suspend, rt715_dev_resume, NULL)
+};
+
+static struct sdw_driver rt715_sdw_driver = {
+	.driver = {
+		.name = "rt715-sdca",
+		.pm = pm_ptr(&rt715_pm),
+	},
+	.probe = rt715_sdca_sdw_probe,
+	.remove = rt715_sdca_sdw_remove,
+	.ops = &rt715_sdca_slave_ops,
+	.id_table = rt715_sdca_id,
+};
+module_sdw_driver(rt715_sdw_driver);
+
+MODULE_DESCRIPTION("ASoC RT715 driver SDW SDCA");
+MODULE_AUTHOR("Jack Yu <jack.yu@realtek.com>");
+MODULE_LICENSE("GPL v2");