From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- drivers/usb/misc/emi26.c | 259 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 259 insertions(+) create mode 100644 drivers/usb/misc/emi26.c (limited to 'drivers/usb/misc/emi26.c') diff --git a/drivers/usb/misc/emi26.c b/drivers/usb/misc/emi26.c new file mode 100644 index 000000000..24d841850 --- /dev/null +++ b/drivers/usb/misc/emi26.c @@ -0,0 +1,259 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Emagic EMI 2|6 usb audio interface firmware loader. + * Copyright (C) 2002 + * Tapio Laxström (tapio.laxstrom@iptime.fi) + * + * emi26.c,v 1.13 2002/03/08 13:10:26 tapio Exp + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#define EMI26_VENDOR_ID 0x086a /* Emagic Soft-und Hardware GmBH */ +#define EMI26_PRODUCT_ID 0x0100 /* EMI 2|6 without firmware */ +#define EMI26B_PRODUCT_ID 0x0102 /* EMI 2|6 without firmware */ + +#define ANCHOR_LOAD_INTERNAL 0xA0 /* Vendor specific request code for Anchor Upload/Download (This one is implemented in the core) */ +#define ANCHOR_LOAD_EXTERNAL 0xA3 /* This command is not implemented in the core. Requires firmware */ +#define ANCHOR_LOAD_FPGA 0xA5 /* This command is not implemented in the core. Requires firmware. Emagic extension */ +#define MAX_INTERNAL_ADDRESS 0x1B3F /* This is the highest internal RAM address for the AN2131Q */ +#define CPUCS_REG 0x7F92 /* EZ-USB Control and Status Register. Bit 0 controls 8051 reset */ +#define INTERNAL_RAM(address) (address <= MAX_INTERNAL_ADDRESS) + +static int emi26_writememory( struct usb_device *dev, int address, + const unsigned char *data, int length, + __u8 bRequest); +static int emi26_set_reset(struct usb_device *dev, unsigned char reset_bit); +static int emi26_load_firmware (struct usb_device *dev); +static int emi26_probe(struct usb_interface *intf, const struct usb_device_id *id); +static void emi26_disconnect(struct usb_interface *intf); + +/* thanks to drivers/usb/serial/keyspan_pda.c code */ +static int emi26_writememory (struct usb_device *dev, int address, + const unsigned char *data, int length, + __u8 request) +{ + int result; + unsigned char *buffer = kmemdup(data, length, GFP_KERNEL); + + if (!buffer) { + dev_err(&dev->dev, "kmalloc(%d) failed.\n", length); + return -ENOMEM; + } + /* Note: usb_control_msg returns negative value on error or length of the + * data that was written! */ + result = usb_control_msg (dev, usb_sndctrlpipe(dev, 0), request, 0x40, address, 0, buffer, length, 300); + kfree (buffer); + return result; +} + +/* thanks to drivers/usb/serial/keyspan_pda.c code */ +static int emi26_set_reset (struct usb_device *dev, unsigned char reset_bit) +{ + int response; + dev_info(&dev->dev, "%s - %d\n", __func__, reset_bit); + /* printk(KERN_DEBUG "%s - %d", __func__, reset_bit); */ + response = emi26_writememory (dev, CPUCS_REG, &reset_bit, 1, 0xa0); + if (response < 0) { + dev_err(&dev->dev, "set_reset (%d) failed\n", reset_bit); + } + return response; +} + +#define FW_LOAD_SIZE 1023 + +static int emi26_load_firmware (struct usb_device *dev) +{ + const struct firmware *loader_fw = NULL; + const struct firmware *bitstream_fw = NULL; + const struct firmware *firmware_fw = NULL; + const struct ihex_binrec *rec; + int err = -ENOMEM; + int i; + __u32 addr; /* Address to write */ + __u8 *buf; + + buf = kmalloc(FW_LOAD_SIZE, GFP_KERNEL); + if (!buf) + goto wraperr; + + err = request_ihex_firmware(&loader_fw, "emi26/loader.fw", &dev->dev); + if (err) + goto nofw; + + err = request_ihex_firmware(&bitstream_fw, "emi26/bitstream.fw", + &dev->dev); + if (err) + goto nofw; + + err = request_ihex_firmware(&firmware_fw, "emi26/firmware.fw", + &dev->dev); + if (err) { + nofw: + dev_err(&dev->dev, "%s - request_firmware() failed\n", + __func__); + goto wraperr; + } + + /* Assert reset (stop the CPU in the EMI) */ + err = emi26_set_reset(dev,1); + if (err < 0) + goto wraperr; + + rec = (const struct ihex_binrec *)loader_fw->data; + /* 1. We need to put the loader for the FPGA into the EZ-USB */ + while (rec) { + err = emi26_writememory(dev, be32_to_cpu(rec->addr), + rec->data, be16_to_cpu(rec->len), + ANCHOR_LOAD_INTERNAL); + if (err < 0) + goto wraperr; + rec = ihex_next_binrec(rec); + } + + /* De-assert reset (let the CPU run) */ + err = emi26_set_reset(dev,0); + if (err < 0) + goto wraperr; + msleep(250); /* let device settle */ + + /* 2. We upload the FPGA firmware into the EMI + * Note: collect up to 1023 (yes!) bytes and send them with + * a single request. This is _much_ faster! */ + rec = (const struct ihex_binrec *)bitstream_fw->data; + do { + i = 0; + addr = be32_to_cpu(rec->addr); + + /* intel hex records are terminated with type 0 element */ + while (rec && (i + be16_to_cpu(rec->len) < FW_LOAD_SIZE)) { + memcpy(buf + i, rec->data, be16_to_cpu(rec->len)); + i += be16_to_cpu(rec->len); + rec = ihex_next_binrec(rec); + } + err = emi26_writememory(dev, addr, buf, i, ANCHOR_LOAD_FPGA); + if (err < 0) + goto wraperr; + } while (rec); + + /* Assert reset (stop the CPU in the EMI) */ + err = emi26_set_reset(dev,1); + if (err < 0) + goto wraperr; + + /* 3. We need to put the loader for the firmware into the EZ-USB (again...) */ + for (rec = (const struct ihex_binrec *)loader_fw->data; + rec; rec = ihex_next_binrec(rec)) { + err = emi26_writememory(dev, be32_to_cpu(rec->addr), + rec->data, be16_to_cpu(rec->len), + ANCHOR_LOAD_INTERNAL); + if (err < 0) + goto wraperr; + } + msleep(250); /* let device settle */ + + /* De-assert reset (let the CPU run) */ + err = emi26_set_reset(dev,0); + if (err < 0) + goto wraperr; + + /* 4. We put the part of the firmware that lies in the external RAM into the EZ-USB */ + + for (rec = (const struct ihex_binrec *)firmware_fw->data; + rec; rec = ihex_next_binrec(rec)) { + if (!INTERNAL_RAM(be32_to_cpu(rec->addr))) { + err = emi26_writememory(dev, be32_to_cpu(rec->addr), + rec->data, be16_to_cpu(rec->len), + ANCHOR_LOAD_EXTERNAL); + if (err < 0) + goto wraperr; + } + } + + /* Assert reset (stop the CPU in the EMI) */ + err = emi26_set_reset(dev,1); + if (err < 0) + goto wraperr; + + for (rec = (const struct ihex_binrec *)firmware_fw->data; + rec; rec = ihex_next_binrec(rec)) { + if (INTERNAL_RAM(be32_to_cpu(rec->addr))) { + err = emi26_writememory(dev, be32_to_cpu(rec->addr), + rec->data, be16_to_cpu(rec->len), + ANCHOR_LOAD_INTERNAL); + if (err < 0) + goto wraperr; + } + } + + /* De-assert reset (let the CPU run) */ + err = emi26_set_reset(dev,0); + if (err < 0) + goto wraperr; + msleep(250); /* let device settle */ + + /* return 1 to fail the driver inialization + * and give real driver change to load */ + err = 1; + +wraperr: + if (err < 0) + dev_err(&dev->dev,"%s - error loading firmware: error = %d\n", + __func__, err); + + release_firmware(loader_fw); + release_firmware(bitstream_fw); + release_firmware(firmware_fw); + + kfree(buf); + return err; +} + +static const struct usb_device_id id_table[] = { + { USB_DEVICE(EMI26_VENDOR_ID, EMI26_PRODUCT_ID) }, + { USB_DEVICE(EMI26_VENDOR_ID, EMI26B_PRODUCT_ID) }, + { } /* Terminating entry */ +}; + +MODULE_DEVICE_TABLE (usb, id_table); + +static int emi26_probe(struct usb_interface *intf, const struct usb_device_id *id) +{ + struct usb_device *dev = interface_to_usbdev(intf); + + dev_info(&intf->dev, "%s start\n", __func__); + + emi26_load_firmware(dev); + + /* do not return the driver context, let real audio driver do that */ + return -EIO; +} + +static void emi26_disconnect(struct usb_interface *intf) +{ +} + +static struct usb_driver emi26_driver = { + .name = "emi26 - firmware loader", + .probe = emi26_probe, + .disconnect = emi26_disconnect, + .id_table = id_table, +}; + +module_usb_driver(emi26_driver); + +MODULE_AUTHOR("Tapio Laxström"); +MODULE_DESCRIPTION("Emagic EMI 2|6 firmware loader."); +MODULE_LICENSE("GPL"); + +MODULE_FIRMWARE("emi26/loader.fw"); +MODULE_FIRMWARE("emi26/bitstream.fw"); +MODULE_FIRMWARE("emi26/firmware.fw"); +/* vi:ai:syntax=c:sw=8:ts=8:tw=80 + */ -- cgit v1.3.1