Merge tag 'v3.2-rc7' into staging/for_v3.3

Linux 3.2-rc7

* tag 'v3.2-rc7': (1304 commits)
  Linux 3.2-rc7
  netfilter: xt_connbytes: handle negation correctly
  Btrfs: call d_instantiate after all ops are setup
  Btrfs: fix worker lock misuse in find_worker
  net: relax rcvbuf limits
  rps: fix insufficient bounds checking in store_rps_dev_flow_table_cnt()
  net: introduce DST_NOPEER dst flag
  mqprio: Avoid panic if no options are provided
  bridge: provide a mtu() method for fake_dst_ops
  md/bitmap: It is OK to clear bits during recovery.
  md: don't give up looking for spares on first failure-to-add
  md/raid5: ensure correct assessment of drives during degraded reshape.
  md/linear: fix hot-add of devices to linear arrays.
  sparc64: Fix MSIQ HV call ordering in pci_sun4v_msiq_build_irq().
  pata_of_platform: Add missing CONFIG_OF_IRQ dependency.
  ipv4: using prefetch requires including prefetch.h
  VFS: Fix race between CPU hotplug and lglocks
  vfs: __read_cache_page should use gfp argument rather than GFP_KERNEL
  USB: Fix usb/isp1760 build on sparc
  net: Add a flow_cache_flush_deferred function
  ...

Conflicts:
	drivers/media/common/tuners/tda18218.c
	drivers/media/video/omap3isp/ispccdc.c
	drivers/staging/media/as102/as102_drv.h

1 files changed, 23 insertions, 7 deletions

diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 512c49f98e8..8e0924f5544 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -36,6 +36,7 @@
 
 #include <linux/kmod.h>
 #include <linux/nsproxy.h>
+#include <linux/ratelimit.h>
 
 /*
  *	This guards the refcounted line discipline lists. The lock
@@ -547,15 +548,16 @@ static void tty_ldisc_flush_works(struct tty_struct *tty)
 /**
  *	tty_ldisc_wait_idle	-	wait for the ldisc to become idle
  *	@tty: tty to wait for
+ *	@timeout: for how long to wait at most
  *
  *	Wait for the line discipline to become idle. The discipline must
  *	have been halted for this to guarantee it remains idle.
  */
-static int tty_ldisc_wait_idle(struct tty_struct *tty)
+static int tty_ldisc_wait_idle(struct tty_struct *tty, long timeout)
 {
-	int ret;
+	long ret;
 	ret = wait_event_timeout(tty_ldisc_idle,
-			atomic_read(&tty->ldisc->users) == 1, 5 * HZ);
+			atomic_read(&tty->ldisc->users) == 1, timeout);
 	if (ret < 0)
 		return ret;
 	return ret > 0 ? 0 : -EBUSY;
@@ -665,7 +667,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
 
 	tty_ldisc_flush_works(tty);
 
-	retval = tty_ldisc_wait_idle(tty);
+	retval = tty_ldisc_wait_idle(tty, 5 * HZ);
 
 	tty_lock();
 	mutex_lock(&tty->ldisc_mutex);
@@ -762,8 +764,6 @@ static int tty_ldisc_reinit(struct tty_struct *tty, int ldisc)
 	if (IS_ERR(ld))
 		return -1;
 
-	WARN_ON_ONCE(tty_ldisc_wait_idle(tty));
-
 	tty_ldisc_close(tty, tty->ldisc);
 	tty_ldisc_put(tty->ldisc);
 	tty->ldisc = NULL;
@@ -838,7 +838,7 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 	tty_unlock();
 	cancel_work_sync(&tty->buf.work);
 	mutex_unlock(&tty->ldisc_mutex);
-
+retry:
 	tty_lock();
 	mutex_lock(&tty->ldisc_mutex);
 
@@ -847,6 +847,22 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 	   it means auditing a lot of other paths so this is
 	   a FIXME */
 	if (tty->ldisc) {	/* Not yet closed */
+		if (atomic_read(&tty->ldisc->users) != 1) {
+			char cur_n[TASK_COMM_LEN], tty_n[64];
+			long timeout = 3 * HZ;
+			tty_unlock();
+
+			while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) {
+				timeout = MAX_SCHEDULE_TIMEOUT;
+				printk_ratelimited(KERN_WARNING
+					"%s: waiting (%s) for %s took too long, but we keep waiting...\n",
+					__func__, get_task_comm(cur_n, current),
+					tty_name(tty, tty_n));
+			}
+			mutex_unlock(&tty->ldisc_mutex);
+			goto retry;
+		}
+
 		if (reset == 0) {
 
 			if (!tty_ldisc_reinit(tty, tty->termios->c_line))