diff options
| author | Jiri Kosina <jkosina@suse.cz> | 2007-10-20 00:05:19 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-10-25 12:18:45 -0700 |
| commit | acd2a847e7fee7df11817f67dba75a2802793e5d (patch) | |
| tree | 7eba6fe6c15f5f11ffdec779c9979f1ec6b4c6b9 /drivers/usb/serial | |
| parent | 8a28dea3accda319d51a1bf4d3e280771d946f78 (diff) | |
USB: usbserial - fix potential deadlock between write() and IRQ
USB: usbserial - fix potential deadlock between write() and IRQ
usb_serial_generic_write() doesn't disable interrupts when taking port->lock,
and could therefore deadlock with usb_serial_generic_read_bulk_callback()
being called from interrupt, taking the same lock. Fix it.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Larry Finger <larry.finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/serial')
| -rw-r--r-- | drivers/usb/serial/generic.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 88a2c7dce335..9eb4a65ee4d9 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -208,14 +208,15 @@ int usb_serial_generic_write(struct usb_serial_port *port, const unsigned char * /* only do something if we have a bulk out endpoint */ if (serial->num_bulk_out) { - spin_lock_bh(&port->lock); + unsigned long flags; + spin_lock_irqsave(&port->lock, flags); if (port->write_urb_busy) { - spin_unlock_bh(&port->lock); + spin_unlock_irqrestore(&port->lock, flags); dbg("%s - already writing", __FUNCTION__); return 0; } port->write_urb_busy = 1; - spin_unlock_bh(&port->lock); + spin_unlock_irqrestore(&port->lock, flags); count = (count > port->bulk_out_size) ? port->bulk_out_size : count; |