linux-sg2042/drivers/tty
Peter Hurley 7fd6f640f2 serial: 8250_dw: Fix deadlock in LCR workaround
Trying to write console output from within the serial console driver
while the port->lock is held causes recursive deadlock:

  CPU 0
spin_lock_irqsave(&port->lock)
printk()
  console_unlock()
    call_console_drivers()
      serial8250_console_write()
        spin_lock_irqsave(&port->lock)
** DEADLOCK **

The 8250_dw i/o accessors try to write a console error message if the
LCR workaround was unsuccessful. When the port->lock is already held
(eg., when called from serial8250_set_termios()), this deadlocks.

Make the error message a FIXME until a general solution is devised.

Cc: Tim Kryger <tim.kryger@gmail.com>
Reported-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-11 16:39:52 +01:00
..
hvc s390/hvc_iucv: add simple wildcard matches to the iucv allow filter 2015-01-22 12:16:56 +01:00
ipwireless tty: ipwireless: Fix probable mask then right shift defects 2014-11-05 20:06:33 -08:00
serial serial: 8250_dw: Fix deadlock in LCR workaround 2015-03-11 16:39:52 +01:00
vt vt: provide notifications on selection changes 2015-02-02 10:09:54 -08:00
Kconfig drivers/tty: ehv_bytechan fails to build as a module 2014-01-09 17:52:12 -06:00
Makefile
amiserial.c TTY: fix misspelling of current function in string 2015-01-09 14:38:15 -08:00
bfin_jtag_comm.c TTY: bfin_jtag_comm: remove incorrect wait_until_sent operation 2015-03-07 03:44:14 +01:00
cyclades.c tty: Remove tty_hung_up_p() tests from tty drivers' open() 2014-07-10 16:06:49 -07:00
ehv_bytechan.c tty: remove unused variable sprop 2015-02-03 15:52:13 -08:00
goldfish.c goldfish: off by one in goldfish_tty_console_setup() 2014-11-05 16:12:45 -08:00
isicom.c tty/isicom: fix big-endian compile warning 2015-02-02 10:11:25 -08:00
metag_da.c tty/metag_da: Add console_poll module parameter 2014-09-28 21:35:56 -04:00
moxa.c TTY: fix decimal printf format specifiers prefixed with 0x 2014-09-08 15:51:35 -07:00
moxa.h
mxser.c
mxser.h
n_gsm.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-08-06 09:38:14 -07:00
n_hdlc.c drivers/tty/n_hdlc.c: replace kmalloc/memset by kzalloc 2014-05-28 13:33:18 -07:00
n_r3964.c tty: Always handle NULL flag ptr 2013-12-08 16:56:05 -08:00
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c n_tty: Fix signal handling flushes 2015-02-02 10:11:27 -08:00
nozomi.c drivers/tty/nozomi.c: Use 'nozomi_setup_memory' instead of 'setup_memory' 2014-09-08 16:09:23 -07:00
pty.c n_tty: Fix signal handling flushes 2015-02-02 10:11:27 -08:00
rocket.c TTY: fix misspelling of current function in string 2015-01-09 14:38:15 -08:00
rocket.h
rocket_int.h
synclink.c tty: Remove tty_hung_up_p() tests from tty drivers' open() 2014-07-10 16:06:49 -07:00
synclink_gt.c synclink_gt: use pci_zalloc_consistent 2014-08-08 15:57:30 -07:00
synclinkmp.c tty: Remove tty_hung_up_p() tests from tty drivers' open() 2014-07-10 16:06:49 -07:00
sysrq.c oom, PM: make OOM detection in the freezer path raceless 2015-02-11 17:06:03 -08:00
tty_audit.c audit: anchor all pid references in the initial pid namespace 2014-03-20 10:11:55 -04:00
tty_buffer.c pty: Fix buffer flush deadlock 2015-02-02 10:11:27 -08:00
tty_io.c tty: fix up atime/mtime mess, take four 2015-03-07 03:06:51 +01:00
tty_ioctl.c TTY: fix tty_wait_until_sent maximum timeout 2015-03-07 03:44:15 +01:00
tty_ldisc.c tty: Allow safe access to termios for set_ldisc() handlers 2014-11-06 14:57:27 -08:00
tty_ldsem.c lockdep: Make held_lock->check and "int check" argument bool 2014-02-09 21:18:54 +01:00
tty_mutex.c tty: Make lock subclasses available for other tty locks 2015-02-02 10:11:27 -08:00
tty_port.c tty: Deletion of unnecessary checks before two function calls 2014-11-26 19:35:49 -08:00