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| author | Oliver Barta <o.barta89@gmail.com> | 2019-06-19 10:16:39 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-21 11:07:34 +0200 |
| commit | 3f2640ed7be838c3f05c0d2b0f7c7508e7431e48 (patch) | |
| tree | 9630fa6628ec325530a9395e4dd5ee60d26e7330 | |
| parent | 4a96895f74c9633b51427fd080ab70fa62b65bc4 (diff) | |
| download | linux-3f2640ed7be838c3f05c0d2b0f7c7508e7431e48.tar.bz2 | |
Revert "serial: 8250: Don't service RX FIFO if interrupts are disabled"
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>
| -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 a6fabc7e3b13..c1cec808571b 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1867,8 +1867,7 @@ 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); } |