diff options
| author |   Jiri Slaby <jslaby@suse.cz> | 2011-04-20 10:43:15 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@suse.de> | 2011-04-25 14:19:11 -0700 |
| commit | 0ad7c9af3e1cbb97082062266705d6cb5fb207ee (patch) | |
| tree | 7934df8bfa67d18d21e9d9ee7f9efc6a431854a6 /drivers/tty | |
| parent | Char: nozomi, remove useless tty_sem (diff) | |
| download | linux-dev-0ad7c9af3e1cbb97082062266705d6cb5fb207ee.tar.xz linux-dev-0ad7c9af3e1cbb97082062266705d6cb5fb207ee.zip | |
Char: moxa, fix locking in moxa_write
moxa_write can be called from atomic context with irqs disabled (from
ppp_async_push). Don't enable interrupts by spin_unlock_bh as this
might cause deadlocks in the ppp layer.
Instead, use irqsave/irqrestore spin_lock functions.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/moxa.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/tty/moxa.c b/drivers/tty/moxa.c index a290e9ebafe0..6255561dd2a3 100644 --- a/drivers/tty/moxa.c +++ b/drivers/tty/moxa.c @@ -1202,14 +1202,15 @@ static int moxa_write(struct tty_struct *tty, const unsigned char *buf, int count) { struct moxa_port *ch = tty->driver_data; + unsigned long flags; int len; if (ch == NULL) return 0; - spin_lock_bh(&moxa_lock); + spin_lock_irqsave(&moxa_lock, flags); len = MoxaPortWriteData(tty, buf, count); - spin_unlock_bh(&moxa_lock); + spin_unlock_irqrestore(&moxa_lock, flags); set_bit(LOWWAIT, &ch->statusflags); return len; |