Does block_sigmask() + tracehook_signal_handler();  called when
sigframe has been successfully built.  All architectures converted
to it; block_sigmask() itself is gone now (merged into this one).

I'm still not too happy with the signature, but that's a separate
story (IMO we need a structure that would contain signal number +
siginfo + k_sigaction, so that get_signal_to_deliver() would fill one,
signal_delivered(), handle_signal() and probably setup...frame() -
take one).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Only 3 out of 63 do not.  Renamed the current variant to __set_current_blocked(),
added set_current_blocked() that will exclude unblockable signals, switched
open-coded instances to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

replace boilerplate "should we use ->saved_sigmask or ->blocked?"
with calls of obvious inlined helper...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

first fruits of ..._restore_sigmask() helpers: now we can take
boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK
and restore the blocked mask from ->saved_mask" into a common
helper.  Open-coded instances switched...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull second pile of signal handling patches from Al Viro:
 "This one is just task_work_add() series + remaining prereqs for it.

  There probably will be another pull request from that tree this
  cycle - at least for helpers, to get them out of the way for per-arch
  fixes remaining in the tree."

Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile
had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the
pr_foo() infrastructure to prefix printks") which changed one of the
pr_err() calls that this merge moves around.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  keys: kill task_struct->replacement_session_keyring
  keys: kill the dummy key_replace_session_keyring()
  keys: change keyctl_session_to_parent() to use task_work_add()
  genirq: reimplement exit_irq_thread() hook via task_work_add()
  task_work_add: generic process-context callbacks
  avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers
  parisc: need to check NOTIFY_RESUME when exiting from syscall
  move key_repace_session_keyring() into tracehook_notify_resume()
  TIF_NOTIFY_RESUME is defined on all targets now

Pull MIPS updates from Ralf Baechle:
 "The whole series has been sitting in -next for quite a while with no
  complaints.  The last change to the series was before the weekend the
  removal of an SPI patch which Grant - even though previously acked by
  himself - appeared to raise objections.  So I removed it until the
  situation is clarified.  Other than that all the patches have the acks
  from their respective maintainers, all MIPS and x86 defconfigs are
  building fine and I'm not aware of any problems introduced by this
  series.

  Among the key features for this patch series is a sizable patchset for
  Lantiq which among other things introduces support for Lantiq's
  flagship product, the FALCON SOC.  It also means that the opensource
  developers behind this patchset have overtaken Lantiq's competing
  inhouse development team that was working behind closed doors.

  Less noteworthy the ath79 patchset which adds support for a few more
  chip variants, cleanups and fixes.  Finally the usual dose of tweaking
  of generic code."

Fix up trivial conflicts in arch/mips/lantiq/xway/gpio_{ebu,stp}.c where
printk spelling fixes clashed with file move and eventual removal of the
printk.

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (81 commits)
  MIPS: lantiq: remove orphaned code
  MIPS: Remove all -Wall and almost all -Werror usage from arch/mips.
  MIPS: lantiq: implement support for FALCON soc
  MTD: MIPS: lantiq: verify that the NOR interface is available on falcon soc
  MTD: MIPS: lantiq: implement OF support
  watchdog: MIPS: lantiq: implement OF support and minor fixes
  SERIAL: MIPS: lantiq: implement OF support
  GPIO: MIPS: lantiq: convert gpio-stp-xway to OF
  GPIO: MIPS: lantiq: convert gpio-mm-lantiq to OF and of_mm_gpio
  GPIO: MIPS: lantiq: move gpio-stp and gpio-ebu to the subsystem folder
  MIPS: pci: convert lantiq driver to OF
  MIPS: lantiq: convert dma to platform driver
  MIPS: lantiq: implement support for clkdev api
  MIPS: lantiq: drop ltq_gpio_request() and gpio_to_irq()
  OF: MIPS: lantiq: implement irq_domain support
  OF: MIPS: lantiq: implement OF support
  MIPS: lantiq: drop mips_machine support
  OF: PCI: const usage needed by MIPS
  MIPS: Cavium: Remove smp_reserve_lock.
  MIPS: Move cache setup to setup_arch().
  ...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>