From: Soren Brinkmann <soren.brinkmann@xilinx.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>
CC: Michal Simek <michal.simek@xilinx.com>, <linux-serial@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        "Soren Brinkmann" <soren.brinkmann@xilinx.com>
Subject: [PATCH 0/9] tty: xuartps: Fix lock ups
Date: Tue, 3 Nov 2015 16:20:41 -0800
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Hi,

I recently found my system locking up under some conditions. I dug
through the code a bit and the result is this collections of various
changes. Some of it may not be required and has just been created out of
half-baked theories and re-reading the documentation. The actual failing
scenarios seem to be:
 - RX IRQ conditions are handled while the receiver is disabled, leaving
   the driver in an infinite loop
 - console_put_char seems to be interrupted by uart_shutdown disabling
   the transmitter while/just before printing

I.e. overall I tried to serialize all operations using the port lock to
avoid such interaction.

	Sören

Sören Brinkmann (9):
  tty: xuartps: Beautify read-modify writes
  tty: xuartps: Use spinlock to serialize HW access
  tty: xuartps: Always enable transmitter in start_tx
  tty: xuartps: Clear interrupt status register in shutdown
  tty: xuartps: Improve startup function
  tty: xuartps: Keep lock for whole ISR
  tty: xuartps: Acquire port lock for shutdown
  tty: xuartps: Move RX path into helper function
  tty: xuartps: Only handle RX IRQs when RX is enabled

 drivers/tty/serial/xilinx_uartps.c | 129 ++++++++++++++++++++++---------------
 1 file changed, 78 insertions(+), 51 deletions(-)

-- 
2.6.2.3.ga463a5b

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