On 07/31/2013 01:50 PM, Peter Hurley wrote:
On 07/29/2013 11:08 AM, Gianluca Anzolin wrote:
This patchset addresses an issue with the rfcomm tty driver in the
current stable kernels that manifests itself as a sudden lockup of the
whole machine or as a OOPS if we are lucky enough (I wasn't).
Triggering the problem is very easy:
1) establish a bluetooth connection with a bluetooth host
2) open the tty it provides with some program
3) turn off the bluetooth host or take it out of range
After a timeout the machine freezes.
Another way to trigger these lockups is to simply release the rfcomm
tty.
This happens beacuse the underlying tty_struct objects and tty_port
objects are freed while being used: the code doesn't take proper
references to them.
The following patches address the problem by implementing a proper
tty_port driver for rfcomm.
There are still some issues left: one relevant to flow control (which is
also missing in the current code) and another relevant to a corner case
in rfcomm_dev_state_change() that I intend to fix with a future patch.
They are commented with a FIXME.
Changes from v4:
[PATCH 3/6]: left the debug message in rfcomm_tty_open()
[PATCH 5/6]: always use !test_and_set_bit() to release the tty_port
I reviewed these changes and retested. All ok.
Gustavo,
This series fixes a crashing regression from 3.10+ forward.
Why is this not in linux-next yet?
Regards,
Peter Hurley
Gianluca Anzolin (6):
rfcomm: Take proper tty_struct references
rfcomm: Remove the device from the list in the destructor
rfcomm: Move the tty initialization and cleanup out of open/close
rfcomm: Implement .activate, .shutdown and .carrier_raised methods
rfcomm: Fix the reference counting of tty_port
rfcomm: Purge the dlc->tx_queue to avoid circular dependency
net/bluetooth/rfcomm/tty.c | 271 +++++++++++++++++++++------------------------
1 file changed, 126 insertions(+), 145 deletions(-)
--
To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
