We store it in the tag set, we don't need it in the hardware queue.
While removing cmd_size, place ->queue_num further down to avoid
a hole on 64-bit archs. It's not used in any fast paths, so we
can safely move it.
Signed-off-by: NJens Axboe <axboe@fb.com>

Check IS_ERR_OR_NULL(return value) instead of just return value.
Signed-off-by: NMing Lei <ming.lei@canonical.com>

Reduced to IS_ERR() by me, we never return NULL.
Signed-off-by: NJens Axboe <axboe@fb.com>

If it's dying, we can't expect new request to complete and come
in an wake up other tasks waiting for requests. So after we
have marked it as dying, wake up everybody currently waiting
for a request. Once they wake, they will retry their allocation
and fail appropriately due to the state of the queue.
Tested-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Sets the vector to an invalid value after it's freed so we don't free
it twice.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Let drivers prevent entering a queue that isn't available.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Fixes usage counter when a request could not be allocated.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Pull vfs pile #3 from Al Viro:
 "Assorted fixes and patches from the last cycle"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  [regression] chunk lost from bd9b51
  vfs: make mounts and mountstats honor root dir like mountinfo does
  vfs: cleanup show_mountinfo
  init: fix read-write root mount
  unfuck binfmt_misc.c (broken by commit e6084d4a)
  vm_area_operations: kill ->migrate()
  new helper: iter_is_iovec()
  move_extent_per_page(): get rid of unused w_flags
  lustre: get rid of playing with ->fs
  btrfs: filp_open() returns ERR_PTR() on failure, not NULL...

Merge tag 'ecryptfs-3.19-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull eCryptfs fixes from Tyler Hicks:
 "Fixes for filename decryption and encrypted view plus a cleanup

   - The filename decryption routines were, at times, writing a zero
     byte one character past the end of the filename buffer

   - The encrypted view feature attempted, and failed, to roll its own
     form of enforcing a read-only mount instead of letting the VFS
     enforce it"

* tag 'ecryptfs-3.19-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: Remove buggy and unnecessary write in file name decode routine
  eCryptfs: Remove unnecessary casts when parsing packet lengths
  eCryptfs: Force RO mount when encrypted view is enabled

Pull more btrfs updates from Chris Mason:
 "This is part two of our merge window patches.

  These are all from Filipe, and fix some really hard to find races that
  can cause corruptions.  Most of them involved block group removal
  (balance) or discard"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: remove non-sense btrfs_error_discard_extent() function
  Btrfs: fix fs corruption on transaction abort if device supports discard
  Btrfs: always clear a block group node when removing it from the tree
  Btrfs: ensure deletion from pinned_chunks list is protected

Pull sound fixes from Takashi Iwai:
 "Here are a few fixes that have landed after the previous pull request.
  All are driver specific fixes including:

   - error/int value fixes in OXFW,
   - Intel Skylake HD-audio HDMI codec support,
   - Additional HD-audio Realtek codecs and AD1986A codec fixes/quirks,
   - a few more DSD support and a quirk for Arcam rPAC in usb-audio,
   - a typo fix for Scarlett 6i6,
   - fixes for new ASIHPI firmware,
   - ASoC Exynos7 cleanups,
   - Intel ACPI support, and
   - a fix for PCM512 register cache sync"

* tag 'sound-fix-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (24 commits)
  ALSA: usb-audio: extend KEF X300A FU 10 tweak to Arcam rPAC
  ALSA: hda/realtek - New codec support for ALC298
  ALSA: asihpi: update to HPI version 4.14
  ALSA: asihpi: increase tuner pad cache size
  ALSA: asihpi: relax firmware version check
  ALSA: usb-audio: Fix Scarlett 6i6 initialization typo
  ALSA: hda - Add quirk for Packard Bell EasyNote MX65
  ALSA: usb-audio: add native DSD support for Matrix Audio DACs
  ALSA: hda/realtek - New codec support for ALC256
  ALSA: hda/realtek - Add new Dell desktop for ALC3234 headset mode
  ASoC: Intel: fix possible acpi enumeration panic
  ALSA: hda/hdmi - apply Haswell fix-ups to Skylake display codec
  ASoC: Intel: fix return value check in sst_acpi_probe()
  ALSA: hda - Make add_stereo_mix_input flag tristate
  ALSA: hda - Create capture source ctls when stereo mix input is added
  ALSA: hda - Fix typos in snd_hda_get_int_hint() kerneldoc comments
  ALSA: hda - add codec ID for Skylake display audio codec
  ALSA: oxfw: some signedness bugs
  ALSA: oxfw: fix detect_loud_models() return value
  ASoC: rt5677: add REGMAP_I2C and REGMAP_IRQ dependency
  ...

Pull SCSI target fixes from Nicholas Bellinger:
 "The highlights this merge window include:

   - Allow target fabric drivers to function as built-in.  (Roland)
   - Fix tcm_loop multi-TPG endpoint nexus bug.  (Hannes)
   - Move per device config_item_type into se_subsystem_api, allowing
     configfs attributes to be defined at module_init time.  (Jerome +
     nab)
   - Convert existing IBLOCK/FILEIO/RAMDISK/PSCSI/TCMU drivers to use
     external configfs attributes.  (nab)
   - A number of iser-target fixes related to active session + network
     portal shutdown stability during extended stress testing.  (Sagi +
     Slava)
   - Dynamic allocation of T10-PI contexts for iser-target, fixing a
     potentially bogus iscsi_np->tpg_np pointer reference in >= v3.14
     code.  (Sagi)
   - iser-target performance + scalability improvements.  (Sagi)
   - Fixes for SPC-4 Persistent Reservation AllRegistrants spec
     compliance.  (Ilias + James + nab)
   - Avoid potential short kern_sendmsg() in iscsi-target for now until
     Al's conversion to use msghdr iteration is merged post -rc1.
     (Viro)

  Also, Sagi has requested a number of iser-target patches (9) that
  address stability issues he's encountered during extended stress
  testing be considered for v3.10.y + v3.14.y code.  Given the amount of
  LOC involved, it will certainly require extra backporting effort.

  Apologies in advance to Greg-KH & Co on this.  Sagi and I will be
  working post-merge to ensure they each get applied correctly"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (53 commits)
  target: Allow AllRegistrants to re-RESERVE existing reservation
  uapi/linux/target_core_user.h: fix headers_install.sh badness
  iscsi-target: Fail connection on short sendmsg writes
  iscsi-target: nullify session in failed login sequence
  target: Avoid dropping AllRegistrants reservation during unregister
  target: Fix R_HOLDER bit usage for AllRegistrants
  iscsi-target: Drop left-over bogus iscsi_np->tpg_np
  iser-target: Fix wc->wr_id cast warning
  iser-target: Remove code duplication
  iser-target: Adjust log levels and prettify some prints
  iser-target: Use debug_level parameter to control logging level
  iser-target: Fix logout sequence
  iser-target: Don't wait for session commands from completion context
  iser-target: Reduce CQ lock contention by batch polling
  iser-target: Introduce isert_poll_budget
  iser-target: Remove an atomic operation from the IO path
  iser-target: Remove redundant call to isert_conn_terminate
  iser-target: Use single CQ for TX and RX
  iser-target: Centralize completion elements to a context
  iser-target: Cast wr_id with uintptr_t instead of unsinged long
  ...

Pull arch/hexagon updates from Richard Kuo:
 "Build cleanup and a few misc fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rkuo/linux-hexagon-kernel:
  Hexagon: fix signal delivery for debug traps
  Hexagon: set ARCH_DMA_MINALIGN
  Hexagon: fix alignment of init_task in RW_DATA_SECTION
  hexagon: Fix build failures in linux-next

Pull arch/chris updates from Jesper Nilsson:
 "Mostly cleanup and build fixes for CRISv32 allmodconfig

  God Jul och Gott Nytt år!"

* tag 'cris-changes-for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper/cris:
  CRISv32: Remove last remnants of ETRAX_SPI_MMC_BOARD
  CRISv32: ETRAXFS: Fix recursive spinlock
  CRISv32: Select MTDRAM for axisflashmap
  CRISv32: Implement early console
  CRIS: Use KALLSYMs if available in call stack dump
  CRISv32: Fix declaration mismatch
  CRISv32: Rewrite of synchronous serial port driver
  CRIS: Update init memory handling
  CRISv32: Better handling of watchdog bite
  CRIS: Export missing function symbols
  CRIS: Export ioremap_nocache
  CRIS: Fix headers_install
  CRISv32: Add missing include for mm.h
  CRISv32: Drop obsolete file for SPI driver

Pull ia64 __get_cpu_var removal from Tony Luck:
 "__get_cpu_var removed from rest of tree, drop reference from comments
  in arch/ia64"

* tag 'please-pull-misc-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  [IA64] Update comment that references __get_cpu_var

There are no users of this symbol left.
Reported-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Move pinmux alloc/dealloc code into functions that don't take
the spinlock so we can use from code that has the spinlock already.

CRISv32 has no working SMP, so spinlocks becomes a NOP,
so deadlock was never seen.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Fixes compile error on allmodconfig.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Also, print kernel version on oops.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Drop i2c_init from this header, it was declared non-static here,
but static in the C-file.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Make driver possible to load as a module and try to handle
locking better.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

- Add free_initrd_mem as found by Guenter Roeck <linux@roeck-us.net>
- Add free_init_pages
- Export empty_zero_page symbol
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Don't enter watchdog handling if we're already in watchdog handling.

Also some minor formatting tweaks.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

strcmp was lost when all other string functions were removed,
but we still have an optimized version for this on CRISv32,
so any driver built as a module would not have access to this symbol.

In a similar manner, we had optimized versions of
csum_partial_copy_from_user and __do_clear_user
but no exported symbols for them, breaking bunch of other drivers
when built as a module.

At the same time, move EXPORT_SYMBOL(__copy_user) and
EXPORT_SYMBOL(__copy_user_zeroing) C-files so it's
located together with the function definition.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Fix headers_install by adjusting the path to arch files.
And delete unused Kbuild file.
Drop special handling of cris in the headers.sh script
as a nice side-effect.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Fixes the following compile error.

arch/cris/arch-v32/kernel/time.c: In function 'reset_watchdog':
arch/cris/arch-v32/kernel/time.c:121:2:
        error: implicit declaration of function 'global_page_state'
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

File was already deleted.
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>

Pull x86 apic updates from Thomas Gleixner:
 "After stopping the full x86/apic branch, I took some time to go
  through the first block of patches again, which are mostly cleanups
  and preparatory work for the irqdomain conversion and ioapic hotplug
  support.

  Unfortunaly one of the real problematic commits was right at the
  beginning, so I rebased this portion of the pending patches without
  the offenders.

  It would be great to get this into 3.19.  That makes reworking the
  problematic parts simpler.  The usual tip testing did not unearth any
  issues and it is fully bisectible now.

  I'm pretty confident that this wont affect the calmness of the xmas
  season.

  Changes:
   - Split the convoluted io_apic.c code into domain specific parts
     (vector, ioapic, msi, htirq)
   - Introduce proper helper functions to retrieve irq specific data
     instead of open coded dereferencing of pointers
   - Preparatory work for ioapic hotplug and irqdomain conversion
   - Removal of the non functional pci-ioapic driver
   - Removal of unused irq entry stubs
   - Make native_smp_prepare_cpus() preemtible to avoid GFP_ATOMIC
     allocations for everything which is called from there.
   - Small cleanups and fixes"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  iommu/amd: Use helpers to access irq_cfg data structure associated with IRQ
  iommu/vt-d: Use helpers to access irq_cfg data structure associated with IRQ
  x86: irq_remapping: Use helpers to access irq_cfg data structure associated with IRQ
  x86, irq: Use helpers to access irq_cfg data structure associated with IRQ
  x86, irq: Make MSI and HT_IRQ indepenent of X86_IO_APIC
  x86, irq: Move IRQ initialization routines from io_apic.c into vector.c
  x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h
  x86, irq: Move HT IRQ related code from io_apic.c into htirq.c
  x86, irq: Move PCI MSI related code from io_apic.c into msi.c
  x86, irq: Replace printk(KERN_LVL) with pr_lvl() utilities
  x86, irq: Make UP version of irq_complete_move() an inline stub
  x86, irq: Move local APIC related code from io_apic.c into vector.c
  x86, irq: Introduce helpers to access struct irq_cfg
  x86, irq: Protect __clear_irq_vector() with vector_lock
  x86, irq: Rename local APIC related functions in io_apic.c as apic_xxx()
  x86, irq: Refine hw_irq.h to prepare for irqdomain support
  x86, irq: Convert irq_2_pin list to generic list
  x86, irq: Kill useless parameter 'irq_attr' of IO_APIC_get_PCI_irq_vector()
  x86, irq, acpi: Get rid of special handling of GSI for ACPI SCI
  x86, irq: Introduce helper to check whether an IOAPIC has been registered
  ...

Pull NOHZ update from Thomas Gleixner:
 "Remove the call into the nohz idle code from the fake 'idle' thread in
  the powerclamp driver along with the export of those functions which
  was smuggeled in via the thermal tree.  People have tried to hack
  around it in the nohz core code, but it just violates all rightful
  assumptions of that code about the only valid calling context (i.e.
  the proper idle task).

  The powerclamp trainwreck will still work, it just wont get the
  benefit of long idle sleeps"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/powerclamp: Remove tick_nohz_idle abuse

Pull irq core fix from Thomas Gleixner:
 "A single fix plugging a long standing race between proc/stat and
  proc/interrupts access and freeing of interrupt descriptors"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Prevent proc race against freeing of irq descriptors

Pull x86 MPX fixes from Thomas Gleixner:
 "Three updates for the new MPX infrastructure:
   - Use the proper error check in the trap handler
   - Add a proper config option for it
   - Bring documentation up to date"

* 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, mpx: Give MPX a real config option prompt
  x86, mpx: Update documentation
  x86_64/traps: Fix always true condition

Pull x86 fix from Ingo Molnar:
 "This contains a single TLS ABI validation fix from Andy Lutomirski"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tls: Don't validate lm in set_thread_area() after all

Pull perf fixes and cleanups from Ingo Molnar:
 "A kernel fix plus mostly tooling fixes, but also some tooling
  restructuring and cleanups"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  perf: Fix building warning on ARM 32
  perf symbols: Fix use after free in filename__read_build_id
  perf evlist: Use roundup_pow_of_two
  tools: Adopt roundup_pow_of_two
  perf tools: Make the mmap length autotuning more robust
  tools: Adopt rounddown_pow_of_two and deps
  tools: Adopt fls_long and deps
  tools: Move bitops.h from tools/perf/util to tools/
  tools: Introduce asm-generic/bitops.h
  tools lib: Move asm-generic/bitops/find.h code to tools/include and tools/lib
  tools: Whitespace prep patches for moving bitops.h
  tools: Move code originally from asm-generic/atomic.h into tools/include/asm-generic/
  tools: Move code originally from linux/log2.h to tools/include/linux/
  tools: Move __ffs implementation to tools/include/asm-generic/bitops/__ffs.h
  perf evlist: Do not use hard coded value for a mmap_pages default
  perf trace: Let the perf_evlist__mmap autosize the number of pages to use
  perf evlist: Improve the strerror_mmap method
  perf evlist: Clarify sterror_mmap variable names
  perf evlist: Fixup brown paper bag on "hint" for --mmap-pages cmdline arg
  perf trace: Provide a better explanation when mmap fails
  ...

Pull second batch of powerpc updates from Michael Ellerman:
 "The highlight is the series that reworks the idle management on
  powernv, which allows us to use deeper idle states on those machines.

  There's the fix from Anton for the "BUG at kernel/smpboot.c:134!"
  problem.

  An i2c driver for powernv.  This is acked by Wolfram Sang, and he
  asked that we take it through the powerpc tree.

  A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of
  the audit maintainers.

  A patch from Ben to export the symbol map of our OPAL firmware as a
  sysfs file, so that tools can use it.

  Also some CXL fixes, a couple of powerpc perf fixes, a fix for
  smt-enabled, and the patch to add __force to get_user() so we can use
  bitwise types"

* tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
  powerpc/powernv: Ignore smt-enabled on Power8 and later
  powerpc/uaccess: Allow get_user() with bitwise types
  powerpc/powernv: Expose OPAL firmware symbol map
  powernv/powerpc: Add winkle support for offline cpus
  powernv/cpuidle: Redesign idle states management
  powerpc/powernv: Enable Offline CPUs to enter deep idle states
  powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode
  i2c: Driver to expose PowerNV platform i2c busses
  powerpc: add little endian flag to syscall_get_arch()
  power/perf/hv-24x7: Use kmem_cache_free() instead of kfree
  powerpc/perf/hv-24x7: Use per-cpu page buffer
  cxl: Unmap MMIO regions when detaching a context
  cxl: Add timeout to process element commands
  cxl: Change contexts_lock to a mutex to fix sleep while atomic bug
  powerpc: Secondary CPUs must set cpu_callin_map after setting active and online

I'm leaving Red Hat at the end of December 2014, so remove all
references to my soon-to-be-dead address.

(There are some references left in the tree, that need additional
changes, I'll send those through the AGP maintainers).
Signed-off-by: NDave Jones <davej@codemonkey.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 4dbd2771 "tick: export nohz tick idle symbols for module
use" was merged via the thermal tree without an explicit ack from the
relevant maintainers.

The exports are abused by the intel powerclamp driver which implements
a fake idle state from a sched FIFO task. This causes all kinds of
wreckage in the NOHZ core code which rightfully assumes that
tick_nohz_idle_enter/exit() are only called from the idle task itself.

Recent changes in the NOHZ core lead to a failure of the powerclamp
driver and now people try to hack completely broken and backwards
workarounds into the NOHZ core code. This is completely unacceptable
and just papers over the real problem. There are way more subtle
issues lurking around the corner.

The real solution is to fix the powerclamp driver by rewriting it with
a sane concept, but that's beyond the scope of this.

So the only solution for now is to remove the calls into the core NOHZ
code from the powerclamp trainwreck along with the exports. 

Fixes: d6d71ee4 "PM: Introduce Intel PowerClamp Driver"
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Pan Jacob jun <jacob.jun.pan@intel.com>
Cc: LKP <lkp@01.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412181110110.17382@nanosSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Reported-by: NPavel Emelyanov <xemul@parallels.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Commit 85c116a6 ("perf callchain: Make get_srcline fall back to sym+offset")
introduces asprintf() call and matches '%ld' to a u64 argument, which is
incorrect on ARM:

   CC       /home/wn/util/srcline.o
 util/srcline.c: In function 'get_srcline':
 util/srcline.c:297:6: error: format '%ld' expects argument of type 'long int', but argument 4 has type 'u64' [-Werror=format]
 cc1: all warnings being treated as errors
 make[1]: *** [/home/wn/util/srcline.o] Error 1

In addition, all users of get_srcline() use u64 addr, and libbfd
also use 64 bit bfd_vma as address. This patch also fix
prototype of get_srcline() and addr2line() to use u64 addr
instead of unsigned long.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: <lizefan@huawei.com>
Cc: <a.p.zijlstra@chello.nl>
Cc: <paulus@samba.org>
Cc: <acme@kernel.org>
Cc: <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1418710746-35943-1-git-send-email-wangnan0@huawei.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Pull module updates from Rusty Russell:
 "The exciting thing here is the getting rid of stop_machine on module
  removal.  This is possible by using a simple atomic_t for the counter,
  rather than our fancy per-cpu counter: it turns out that no one is
  doing a module increment per net packet, so the slowdown should be in
  the noise"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  param: do not set store func without write perm
  params: cleanup sysfs allocation
  kernel:module Fix coding style errors and warnings.
  module: Remove stop_machine from module unloading
  module: Replace module_ref with atomic_t refcnt
  lib/bug: Use RCU list ops for module_bug_list
  module: Unlink module with RCU synchronizing instead of stop_machine
  module: Wait for RCU synchronizing before releasing a module