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usbserial: fix inconsistent lock state

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In commit acd2a847e7 usb_serial_generic_write()
disables interrupts when taking &port->lock which is also taken in
usb_serial_generic_read_bulk_callback() resulting in an inconsistent lock state
due to the latter not disabling interrupts on the local cpu. Fix that by
disabling interrupts in the latter call site also.

Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Borislav Petkov
2007-10-28 13:24:16 +01:00
committed by Greg Kroah-Hartman
parent ed206ec9ab
commit bfaeafcfc2
1 changed files with 3 additions and 2 deletions
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5
drivers/usb/serial/generic.c
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@@ -327,6 +327,7 @@ void usb_serial_generic_read_bulk_callback (struct urb *urb)
struct usb_serial_port *port = (struct usb_serial_port *)urb->context; struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
unsigned char *data = urb->transfer_buffer; unsigned char *data = urb->transfer_buffer;
int status = urb->status; int status = urb->status;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number); dbg("%s - port %d", __FUNCTION__, port->number);
@@ -339,11 +340,11 @@ void usb_serial_generic_read_bulk_callback (struct urb *urb)
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data); usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
/* Throttle the device if requested by tty */ /* Throttle the device if requested by tty */
spin_lock(&port->lock); spin_lock_irqsave(&port->lock, flags);
if (!(port->throttled = port->throttle_req)) if (!(port->throttled = port->throttle_req))
/* Handle data and continue reading from device */ /* Handle data and continue reading from device */
flush_and_resubmit_read_urb(port); flush_and_resubmit_read_urb(port);
spin_unlock(&port->lock); spin_unlock_irqrestore(&port->lock, flags);
} }
EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback); EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);