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authorDavid Müller <d.mueller@elsoft.ch>2016-04-27 11:58:32 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-06-01 12:15:52 -0700
commit1401ebda89ebf3156984c175209f630e0844f6ce (patch)
parent71378785b6bbeea4098c0dfaca0571b06297224f (diff)
serial: 8250_pci: fix divide error bug if baud rate is 0
commit 6f210c18c1c0f016772c8cd51ae12a02bfb9e7ef upstream. Since commit 21947ba654a6 ("serial: 8250_pci: replace switch-case by formula"), the 8250 driver crashes in the byt_set_termios() function with a divide error. This is caused by the fact that a baud rate of 0 (B0) is not handled properly. Fix it by falling back to B9600 in this case. Signed-off-by: David Müller <d.mueller@elsoft.ch> Fixes: 21947ba654a6 ("serial: 8250_pci: replace switch-case by formula") Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index 7cd6f9a90542..c1d4a8fa9be8 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1401,6 +1401,9 @@ byt_set_termios(struct uart_port *p, struct ktermios *termios,
unsigned long m, n;
u32 reg;
+ /* Gracefully handle the B0 case: fall back to B9600 */
+ fuart = fuart ? fuart : 9600 * 16;
/* Get Fuart closer to Fref */
fuart *= rounddown_pow_of_two(fref / fuart);