Workqueue and serial link

```
What steps will reproduce the problem?
1. Use Vladistan GNU.IO.RXTX
2. Use RS232
3. Send and receive data

What is the expected output? What do you see instead?
The board freezes after a few seconds when sending/receiving adta through RS232:

WARNING: at kernel/workqueue.c:485 flush_cpu_workqueue+0x34/0x88()

Modules linked in: omaplfb libertas pvrsrvkm sdmak lpm_omap3530 dsplinkk cmemk

[] (unwind_backtrace+0x0/0xd8) from []
(warn_slowpath_common

+0x48/0x60)

[] (warn_slowpath_common+0x48/0x60) from []
(flush_cpu_workq

ueue+0x34/0x88)

[] (flush_cpu_workqueue+0x34/0x88) from []
(tty_ldisc_releas
e+0x20/0x68)

[] (tty_ldisc_release+0x20/0x68) from []
(tty_release+0x3c0/
0x420)

[] (tty_release+0x3c0/0x420) from [] (__fput+0x104/0x1d8)

[] (__fput+0x104/0x1d8) from [] (filp_close+0x6c/0x78)

[] (filp_close+0x6c/0x78) from []
(put_files_struct+0x88/0xd
c)

[] (put_files_struct+0x88/0xdc) from []
(binder_deferred_fun

c+0x4e8/0x52c)

[] (binder_deferred_func+0x4e8/0x52c) from []
(worker_thread
+0x150/0x1c4)

[] (worker_thread+0x150/0x1c4) from [] (kthread+0x78/0x80)

[] (kthread+0x78/0x80) from [] (kernel_thread_exit+0x0/0x8)

---[ end trace 4796369df1c2dc82 ]---

binder: 1282: binder_alloc_buf, no vma

binder: 941:968 transaction failed 29201, size 96-0

What version of the product are you using? On what operating system?
linux.2.6.32 kernel.

IGEP enhanced kernel.

Please provide any additional information below.

```

Original issue reported on code.google.com by `ferre.ad...@gmail.com` on 2 May 2011 at 9:17

Start by reproducing the RS232 send/receive freeze on the Linux 2.6.32 IGEP enhanced kernel. Read the warning in kernel/workqueue.c and the tty_ldisc_release trace, along with the binder errors, to determine the failing subsystem. Done means the board no longer freezes and the reported warnings do not recur during serial traffic.

Written by the indexing model from the issue text.