diff options
author | Arnd Bergmann <arnd@arndb.de> | 2014-01-02 13:07:40 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-07 17:05:21 -0800 |
commit | b8c98ae49e8d53344b1d62417eea05ebc3cdbd78 (patch) | |
tree | d50982086efec947214cc960d123afc616429dc9 | |
parent | 591cee0a35632031cd925392a1bce507dcfe9ea8 (diff) |
tty: synclink: avoid sleep_on race
The four variants of the synclink driver use the same code in their
open() callback to wait for a port in process of being closed,
using interruptible_sleep_on, which is racy and going away soon.
Making things worse, these functions hold the BTM while doing so,
which means that if we ever enter this code path, we cannot actually
continue since the other thread that is in process of closing the
port can no longer get the BTM.
This addresses both issues by using wait_event_interruptible_tty()
instead.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/char/pcmcia/synclink_cs.c | 4 | ||||
-rw-r--r-- | drivers/tty/synclink.c | 4 | ||||
-rw-r--r-- | drivers/tty/synclink_gt.c | 4 | ||||
-rw-r--r-- | drivers/tty/synclinkmp.c | 4 |
4 files changed, 8 insertions, 8 deletions
diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c index d39cca659a3..8320abd1ef1 100644 --- a/drivers/char/pcmcia/synclink_cs.c +++ b/drivers/char/pcmcia/synclink_cs.c @@ -2511,8 +2511,8 @@ static int mgslpc_open(struct tty_struct *tty, struct file * filp) /* If port is closing, signal caller to try again */ if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING){ - if (port->flags & ASYNC_CLOSING) - interruptible_sleep_on(&port->close_wait); + wait_event_interruptible_tty(tty, port->close_wait, + !(port->flags & ASYNC_CLOSING)); retval = ((port->flags & ASYNC_HUP_NOTIFY) ? -EAGAIN : -ERESTARTSYS); goto cleanup; diff --git a/drivers/tty/synclink.c b/drivers/tty/synclink.c index e1ce141bad5..5ae14b46cce 100644 --- a/drivers/tty/synclink.c +++ b/drivers/tty/synclink.c @@ -3404,8 +3404,8 @@ static int mgsl_open(struct tty_struct *tty, struct file * filp) /* If port is closing, signal caller to try again */ if (tty_hung_up_p(filp) || info->port.flags & ASYNC_CLOSING){ - if (info->port.flags & ASYNC_CLOSING) - interruptible_sleep_on(&info->port.close_wait); + wait_event_interruptible_tty(tty, info->port.close_wait, + !(info->port.flags & ASYNC_CLOSING)); retval = ((info->port.flags & ASYNC_HUP_NOTIFY) ? -EAGAIN : -ERESTARTSYS); goto cleanup; diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c index 1abf946463f..c359a91f734 100644 --- a/drivers/tty/synclink_gt.c +++ b/drivers/tty/synclink_gt.c @@ -674,8 +674,8 @@ static int open(struct tty_struct *tty, struct file *filp) /* If port is closing, signal caller to try again */ if (tty_hung_up_p(filp) || info->port.flags & ASYNC_CLOSING){ - if (info->port.flags & ASYNC_CLOSING) - interruptible_sleep_on(&info->port.close_wait); + wait_event_interruptible_tty(tty, info->port.close_wait, + !(info->port.flags & ASYNC_CLOSING)); retval = ((info->port.flags & ASYNC_HUP_NOTIFY) ? -EAGAIN : -ERESTARTSYS); goto cleanup; diff --git a/drivers/tty/synclinkmp.c b/drivers/tty/synclinkmp.c index dc6e96996ea..144202eef6f 100644 --- a/drivers/tty/synclinkmp.c +++ b/drivers/tty/synclinkmp.c @@ -754,8 +754,8 @@ static int open(struct tty_struct *tty, struct file *filp) /* If port is closing, signal caller to try again */ if (tty_hung_up_p(filp) || info->port.flags & ASYNC_CLOSING){ - if (info->port.flags & ASYNC_CLOSING) - interruptible_sleep_on(&info->port.close_wait); + wait_event_interruptible_tty(tty, info->port.close_wait, + !(info->port.flags & ASYNC_CLOSING)); retval = ((info->port.flags & ASYNC_HUP_NOTIFY) ? -EAGAIN : -ERESTARTSYS); goto cleanup; |