The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 633e2b2ded739a34bd0fb1d8b5b871f7e489ea29 Mon Sep 17 00:00:00 2001

From: Anthony Mallet anthony.mallet@laas.fr Date: Thu, 12 Mar 2020 14:31:00 +0100 Subject: [PATCH] USB: cdc-acm: fix close_delay and closing_wait units in TIOCSSERIAL

close_delay and closing_wait are specified in hundredth of a second but stored internally in jiffies. Use the jiffies_to_msecs() and msecs_to_jiffies() functions to convert from each other.

Signed-off-by: Anthony Mallet anthony.mallet@laas.fr Cc: stable stable@vger.kernel.org Link: https://lore.kernel.org/r/20200312133101.7096-1-anthony.mallet@laas.fr Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 62f4fb9b362f..da619176deca 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -896,10 +896,10 @@ static int get_serial_info(struct tty_struct *tty, struct serial_struct *ss)

ss->xmit_fifo_size = acm->writesize; ss->baud_base = le32_to_cpu(acm->line.dwDTERate); - ss->close_delay = acm->port.close_delay / 10; + ss->close_delay = jiffies_to_msecs(acm->port.close_delay) / 10; ss->closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ? ASYNC_CLOSING_WAIT_NONE : - acm->port.closing_wait / 10; + jiffies_to_msecs(acm->port.closing_wait) / 10; return 0; }

@@ -909,9 +909,10 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss) unsigned int closing_wait, close_delay; int retval = 0;

- close_delay = ss->close_delay * 10; + close_delay = msecs_to_jiffies(ss->close_delay * 10); closing_wait = ss->closing_wait == ASYNC_CLOSING_WAIT_NONE ? - ASYNC_CLOSING_WAIT_NONE : ss->closing_wait * 10; + ASYNC_CLOSING_WAIT_NONE : + msecs_to_jiffies(ss->closing_wait * 10);

mutex_lock(&acm->port.mutex);