From 55956216f4b42fefaee70060b054359d63d2afa5 Mon Sep 17 00:00:00 2001 From: Nobuhiro Iwamatsu Date: Mon, 29 Aug 2011 15:43:36 +0900 Subject: TTY: serial: Move mutex_unlock in uart_close function When mutex_lock is not called, mutex_unlock is sometimes called. This deletes unnecessary goto and makes modifications so that mutex_unlock is called. [ 8.304000] WARNING: at kernel/muex-debug.c:78 [ 8.304000] Modules linked in: [ 8.304000] [ 8.304000] Pid : 114, Comm: modprobe [ 8.304000] CPU : 0 Not tainted (3.1.0-rc3-next-20110826 #810) [ 8.304000] [ 8.304000] PC is at debug_mutex_unlock+0xf4/0x120 [ 8.304000] PR is at debug_mutex_unlock+0xe6/0x120 [ 8.304000] PC : 80051114 SP : 9f02de58 SR : 400081f1 TEA : 295cf4f2 [ 8.304000] R0 : 00000001 R1 : 00000000 R2 : 0000000f R3 : 00000000 [ 8.304000] R4 : 9fc63158 R5 : 00000000 R6 : 00000001 R7 : 9fe1de78 [ 8.304000] R8 : 805c6b2c R9 : 80003920 R10 : 00000000 R11 : 805c6b2c [ 8.304000] R12 : 80425ca0 R13 : 00000000 R14 : 9f02de58 [ 8.304000] MACH: 00000003 MACL: 00000000 GBR : 296e1678 PR : 80051106 [ 8.304000] [ 8.304000] Call trace: [ 8.304000] [<804236c6>] __mutex_unlock_slowpath+0x46/0x120 [ 8.304000] [<804237aa>] mutex_unlock+0xa/0x20 [ 8.304000] [<80240ed6>] uart_close+0x76/0x2c0 [ 8.304000] [<80223b98>] tty_release+0xf8/0x5c0 [ 8.304000] [<800a93a6>] lookup_object+0x26/0xa0 [ 8.304000] [<80063f6a>] call_rcu+0x8a/0xc0 [ 8.304000] [<800a944a>] put_object+0x2a/0x60 [ 8.304000] [<80003920>] arch_local_irq_restore+0x0/0x40 [ 8.304000] [<800af320>] fput+0x180/0x2c0 [ 8.304000] [<800af248>] fput+0xa8/0x2c0 [ 8.304000] [<800ab1a8>] filp_close+0x48/0xc0 [ 8.304000] [<800ab29a>] sys_close+0x7a/0x100 [ 8.304000] [<8000825a>] syscall_call+0xc/0x10 [ 8.304000] [<800ab220>] sys_close+0x0/0x100 [ 8.304000] [ 8.304000] Code: [ 8.304000] 8005110e: mov.l @r1, r1 [ 8.304000] 80051110: tst r1, r1 [ 8.304000] 80051112: bf 80051116 [ 8.304000] ->80051114: trapa #62 [ 8.304000] 80051116: mov.l @r8, r1 [ 8.304000] 80051118: tst r1, r1 [ 8.304000] 8005111a: bt.s 8005104c [ 8.304000] 8005111c: mov #0, r1 [ 8.304000] 8005111e: bra 80051056 [ 8.304000] [ 8.304000] ---[ end trace e8f8e04c313f429b ]--- Signed-off-by: Nobuhiro Iwamatsu Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/serial_core.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 1d3780cc3b70..a32dc4362224 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1257,7 +1257,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp) if (tty_hung_up_p(filp)) { spin_unlock_irqrestore(&port->lock, flags); - goto done; + return; } if ((tty->count == 1) && (port->count != 1)) { @@ -1279,7 +1279,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp) } if (port->count) { spin_unlock_irqrestore(&port->lock, flags); - goto done; + return; } /* @@ -1342,7 +1342,6 @@ static void uart_close(struct tty_struct *tty, struct file *filp) wake_up_interruptible(&port->open_wait); wake_up_interruptible(&port->close_wait); -done: mutex_unlock(&port->mutex); } -- cgit v1.2.3-59-g8ed1b