| commit | a9ee77af751f435675054f5a7e2d2e69cbfe9e33 | |
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | |
| Thu, 21 Sep 2017 13:51:23 +0000 (21 15:51 +0200) | ||
| committer | Marcel Holtmann <marcel@holtmann.org> | |
| Mon, 30 Oct 2017 08:04:07 +0000 (30 09:04 +0100) | ||
| tree | 75d3524a3d20e74e4d34d0e43b3f9b6ff41fe0cb | treesnapshot (tar.gz zip) |
| parent | 1f01d8be0e6a04bd682a55f6d50c14c1679e7571 | commitdiff |
Bluetooth: avoid recursive locking in hci_send_to_channel()
Mart reported a deadlock in -RT in the call path:
hci_send_monitor_ctrl_event() -> hci_send_to_channel()
because both functions acquire the same read lock hci_sk_list.lock. This
is also a mainline issue because the qrwlock implementation is writer
fair (the traditional rwlock implementation is reader biased).
To avoid the deadlock there is now __hci_send_to_channel() which expects
the readlock to be held.
Fixes: 38ceaa00d02d ("Bluetooth: Add support for sending MGMT commands and events to monitor")
Reported-by: Mart van de Wege <mvdwege@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Mart reported a deadlock in -RT in the call path:
hci_send_monitor_ctrl_event() -> hci_send_to_channel()
because both functions acquire the same read lock hci_sk_list.lock. This
is also a mainline issue because the qrwlock implementation is writer
fair (the traditional rwlock implementation is reader biased).
To avoid the deadlock there is now __hci_send_to_channel() which expects
the readlock to be held.
Fixes: 38ceaa00d02d ("Bluetooth: Add support for sending MGMT commands and events to monitor")
Reported-by: Mart van de Wege <mvdwege@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
| net/bluetooth/hci_sock.c | diffblobblamehistory |