Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 4d8e14b7aa93..dd5e1ac22251 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2343,8 +2343,11 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
 
         /*
          * CTS flow control flag and modem status interrupts
+         * Only disable MSI if no threads are waiting in
+         * serial_core::uart_wait_modem_status
          */
-        up->ier &= ~UART_IER_MSI;
+        if (!waitqueue_active(&up->port.state->port.delta_msr_wait))
+                up->ier &= ~UART_IER_MSI;
         if (!(up->bugs & UART_BUG_NOMSR) &&
                         UART_ENABLE_MS(&up->port, termios->c_cflag))
                 up->ier |= UART_IER_MSI;