diff options
author | Oliver Barta <o.barta89@gmail.com> | 2019-06-19 10:16:39 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-21 09:06:00 +0200 |
commit | 012611e87fedfaa2fed2c8941014e0f3173baf72 (patch) | |
tree | 9553c18ed84baea8f2fb02177fd4ea6535416572 /drivers/tty/serial | |
parent | 072d6445110e375b78995e3c78ac6800d3419053 (diff) |
Revert "serial: 8250: Don't service RX FIFO if interrupts are disabled"
commit 3f2640ed7be838c3f05c0d2b0f7c7508e7431e48 upstream.
This reverts commit 2e9fe539108320820016f78ca7704a7342788380.
Reading LSR unconditionally but processing the error flags only if
UART_IIR_RDI bit was set before in IIR may lead to a loss of transmission
error information on UARTs where the transmission error flags are cleared
by a read of LSR. Information are lost in case an error is detected right
before the read of LSR while processing e.g. an UART_IIR_THRI interrupt.
Signed-off-by: Oliver Barta <o.barta89@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Fixes: 2e9fe5391083 ("serial: 8250: Don't service RX FIFO if interrupts are disabled")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
-rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 5b54439a8a9b..84474f06dbcf 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1814,8 +1814,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) status = serial_port_in(port, UART_LSR); - if (status & (UART_LSR_DR | UART_LSR_BI) && - iir & UART_IIR_RDI) { + if (status & (UART_LSR_DR | UART_LSR_BI)) { if (!up->dma || handle_rx_dma(up, iir)) status = serial8250_rx_chars(up, status); } |