pid: fix lockdep deadlock warning due to ucount_lock

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
4.10.0-rc2-00024-g4aecec9-dirty #118 Tainted: G        W
---------------------------------------------------------
swapper/1/0 just changed the state of lock:
 (&(&sighand->siglock)->rlock){-.....}, at: [<ffffffffbd0a1bc6>] __lock_task_sighand+0xb6/0x2c0
but this lock took another, HARDIRQ-unsafe lock in the past:
 (ucounts_lock){+.+...}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Chain exists of:                 &(&sighand->siglock)->rlock --> &(&tty->ctrl_lock)->rlock --> ucounts_lock
 Possible interrupt unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(ucounts_lock);
                               local_irq_disable();
                               lock(&(&sighand->siglock)->rlock);
                               lock(&(&tty->ctrl_lock)->rlock);
  <Interrupt>
    lock(&(&sighand->siglock)->rlock);

 *** DEADLOCK ***

This patch removes a dependency between rlock and ucount_lock.

Fixes: f333c700c610 ("pidns: Add a limit on the number of pid namespaces")
Cc: stable@vger.kernel.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

path: root/net/nfc/Kconfig

#
# NFC sybsystem configuration
#

menuconfig NFC
	depends on NET
	depends on RFKILL || !RFKILL
	tristate "NFC subsystem support"
	default n
	help
	  Say Y here if you want to build support for NFC (Near field
	  communication) devices.

	  To compile this support as a module, choose M here: the module will
	  be called nfc.

config NFC_DIGITAL
	depends on NFC
	select CRC_CCITT
	select CRC_ITU_T
	tristate "NFC Digital Protocol stack support"
	default n
	help
	  Say Y if you want to build NFC digital protocol stack support.
	  This is needed by NFC chipsets whose firmware only implement
	  the NFC analog layer.

	  To compile this support as a module, choose M here: the module will
	  be called nfc_digital.

source "net/nfc/nci/Kconfig"
source "net/nfc/hci/Kconfig"

source "drivers/nfc/Kconfig"