Merge 4.14-rc4 into tty-next

We want the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 11 insertions, 5 deletions

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 7f7968475736..2497be8a2190 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -246,11 +246,11 @@ struct mxser_port {
         unsigned char err_shadow;
 
         struct async_icount icount; /* kernel counters for 4 input interrupts */
-        int timeout;
+        unsigned int timeout;
 
         int read_status_mask;
         int ignore_status_mask;
-        int xmit_fifo_size;
+        unsigned int xmit_fifo_size;
         int xmit_head;
         int xmit_tail;
         int xmit_cnt;
@@ -572,8 +572,9 @@ static void mxser_dtr_rts(struct tty_port *port, int on)
 static int mxser_set_baud(struct tty_struct *tty, long newspd)
 {
         struct mxser_port *info = tty->driver_data;
-        int quot = 0, baud;
+        unsigned int quot = 0, baud;
         unsigned char cval;
+        u64 timeout;
 
         if (!info->ioaddr)
                 return -1;
@@ -594,8 +595,13 @@ static int mxser_set_baud(struct tty_struct *tty, long newspd)
                 quot = 0;
         }
 
-        info->timeout = ((info->xmit_fifo_size * HZ * 10 * quot) / info->baud_base);
-        info->timeout += HZ / 50;       /* Add .02 seconds of slop */
+        /*
+         * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the
+         * u64 domain
+         */
+        timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot;
+        do_div(timeout, info->baud_base);
+        info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */
 
         if (quot) {
                 info->MCR |= UART_MCR_DTR;