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/image/microtek.h | 55 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 drivers/usb/image/microtek.h (limited to 'drivers/usb/image/microtek.h') diff --git a/drivers/usb/image/microtek.h b/drivers/usb/image/microtek.h new file mode 100644 index 000000000..7bd5f4639 --- /dev/null +++ b/drivers/usb/image/microtek.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + /* + * Driver for Microtek Scanmaker X6 USB scanner and possibly others. + * + * (C) Copyright 2000 John Fremlin + * (C) Copyright 2000 Oliver Neukum + * + * See microtek.c for history + * + */ + +typedef void (*mts_scsi_cmnd_callback)(struct scsi_cmnd *); + + +struct mts_transfer_context +{ + struct mts_desc *instance; + mts_scsi_cmnd_callback final_callback; + struct scsi_cmnd *srb; + + void *data; + unsigned data_length; + int data_pipe; + struct scatterlist *curr_sg; + + u8 *scsi_status; /* status returned from ep_response after command completion */ +}; + + +struct mts_desc { + struct mts_desc *next; + struct mts_desc *prev; + + struct usb_device *usb_dev; + struct usb_interface *usb_intf; + + /* Endpoint addresses */ + u8 ep_out; + u8 ep_response; + u8 ep_image; + + struct Scsi_Host *host; + + struct urb *urb; + struct mts_transfer_context context; +}; + + +#define MTS_EP_OUT 0x1 +#define MTS_EP_RESPONSE 0x2 +#define MTS_EP_IMAGE 0x3 +#define MTS_EP_TOTAL 0x3 + +#define MTS_SCSI_ERR_MASK ~0x3fu + -- cgit v1.3.1