1. 24 4月, 2009 1 次提交
    • A
      USB: serial: fix lifetime and locking problems · 2d93148a
      Alan Stern 提交于
      This patch (as1229) fixes a few lifetime and locking problems in the
      usb-serial driver.  The main symptom is that an invalid kevent is
      created when the serial device is unplugged while a connection is
      active.
      
      	Ports should be unregistered when device is disconnected,
      	not when the parent usb_serial structure is deallocated.
      
      	Each open file should hold a reference to the corresponding
      	port structure, and the reference should be released when
      	the file is closed.
      
      	serial->disc_mutex should be acquired in serial_open(), to
      	resolve the classic race between open and disconnect.
      
      	serial_close() doesn't need to hold both serial->disc_mutex
      	and port->mutex at the same time.
      
      	Release the subdriver's module reference only after releasing
      	all the other references, in case one of the release routines
      	needs to invoke some code in the subdriver module.
      
      	Replace a call to flush_scheduled_work() (which is prone to
      	deadlocks) with cancel_work_sync().  Also, add a call to
      	cancel_work_sync() in the disconnect routine.
      
      	Reduce the scope of serial->disc_mutex in serial_disconnect().
      	The only place it really needs to protect is where the
      	"disconnected" flag is set.
      
      This fixes the bug reported in
      
      	http://bugs.freedesktop.org/show_bug.cgi?id=20703Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Tested-by: NDan Williams <dcbw@redhat.com>
      Tested-by: NMing Lei <tom.leiming@gmail.com>
      Reviewed-by: NOliver Neukum <oliver@neukum.org>
      Acked-by: NAlan Cox <alan@linux.intel.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      
      2d93148a
  2. 22 4月, 2009 35 次提交
  3. 21 4月, 2009 4 次提交