linux-stable.git/Documentation/vm, branch v3.16.67

mm: rmap use pte lock not mmap_sem to set PageMlocked

2019-04-04T15:14:08+00:00

commit b87537d9e2feb30f6a962f27eb32768682698d3b upstream.

KernelThreadSanitizer (ktsan) has shown that the down_read_trylock() of
mmap_sem in try_to_unmap_one() (when going to set PageMlocked on a page
found mapped in a VM_LOCKED vma) is ineffective against races with
exit_mmap()'s munlock_vma_pages_all(), because mmap_sem is not held when
tearing down an mm.

But that's okay, those races are benign; and although we've believed for
years in that ugly down_read_trylock(), it's unsuitable for the job, and
frustrates the good intention of setting PageMlocked when it fails.

It just doesn't matter if here we read vm_flags an instant before or after
a racing mlock() or munlock() or exit_mmap() sets or clears VM_LOCKED: the
syscalls (or exit) work their way up the address space (taking pt locks
after updating vm_flags) to establish the final state.

We do still need to be careful never to mark a page Mlocked (hence
unevictable) by any race that will not be corrected shortly after.  The
page lock protects from many of the races, but not all (a page is not
necessarily locked when it's unmapped).  But the pte lock we just dropped
is good to cover the rest (and serializes even with
munlock_vma_pages_all(), so no special barriers required): now hold on to
the pte lock while calling mlock_vma_page().  Is that lock ordering safe?
Yes, that's how follow_page_pte() calls it, and how page_remove_rmap()
calls the complementary clear_page_mlock().

This fixes the following case (though not a case which anyone has
complained of), which mmap_sem did not: truncation's preliminary
unmap_mapping_range() is supposed to remove even the anonymous COWs of
filecache pages, and that might race with try_to_unmap_one() on a
VM_LOCKED vma, so that mlock_vma_page() sets PageMlocked just after
zap_pte_range() unmaps the page, causing "Bad page state (mlocked)" when
freed.  The pte lock protects against this.

You could say that it also protects against the more ordinary case, racing
with the preliminary unmapping of a filecache page itself: but in our
current tree, that's independently protected by i_mmap_rwsem; and that
race would be why "Bad page state (mlocked)" was seen before commit
48ec833b7851 ("Revert mm/memory.c: share the i_mmap_rwsem").

Vlastimil Babka points out another race which this patch protects against.
 try_to_unmap_one() might reach its mlock_vma_page() TestSetPageMlocked a
moment after munlock_vma_pages_all() did its Phase 1 TestClearPageMlocked:
leaving PageMlocked and unevictable when it should be evictable.  mmap_sem
is ineffective because exit_mmap() does not hold it; page lock ineffective
because __munlock_pagevec() only takes it afterwards, in Phase 2; pte lock
is effective because __munlock_pagevec_fill() takes it to get the page,
after VM_LOCKED was cleared from vm_flags, so visible to try_to_unmap_one.

Kirill Shutemov points out that if the compiler chooses to implement a
"vma->vm_flags &= VM_WHATEVER" or "vma->vm_flags |= VM_WHATEVER" operation
with an intermediate store of unrelated bits set, since I'm here foregoing
its usual protection by mmap_sem, try_to_unmap_one() might catch sight of
a spurious VM_LOCKED in vm_flags, and make the wrong decision.  This does
not appear to be an immediate problem, but we may want to define vm_flags
accessors in future, to guard against such a possibility.

While we're here, make a related optimization in try_to_munmap_one(): if
it's doing TTU_MUNLOCK, then there's no point at all in descending the
page tables and getting the pt lock, unless the vma is VM_LOCKED.  Yes,
that can change racily, but it can change racily even without the
optimization: it's not critical.  Far better not to waste time here.

Stopped short of separating try_to_munlock_one() from try_to_munmap_one()
on this occasion, but that's probably the sensible next step - with a
rename, given that try_to_munlock()'s business is to try to set Mlocked.

Updated the unevictable-lru Documentation, to remove its reference to mmap
semaphore, but found a few more updates needed in just that area.

Signed-off-by: Hugh Dickins 
Cc: Christoph Lameter 
Cc: "Kirill A. Shutemov" 
Cc: Rik van Riel 
Acked-by: Vlastimil Babka 
Cc: Davidlohr Bueso 
Cc: Oleg Nesterov 
Cc: Sasha Levin 
Cc: Dmitry Vyukov 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
[bwh: Backported to 3.16 in preparation for commit 017b1660df89
 "mm: migration: fix migration of huge PMD shared pages". Adjusted context.]
Signed-off-by: Ben Hutchings

mm Documentation: undoc non-linear vmas

2019-04-04T15:14:07+00:00

commit 7a14239a8fff45a241b6943a3ac444d5b67fcbed upstream.

While updating some mm Documentation, I came across a few straggling
references to the non-linear vmas which were happily removed in v4.0.
Delete them.

Signed-off-by: Hugh Dickins 
Cc: Christoph Lameter 
Cc: "Kirill A. Shutemov" 
Cc: Rik van Riel 
Acked-by: Vlastimil Babka 
Cc: Davidlohr Bueso 
Cc: Oleg Nesterov 
Cc: Sasha Levin 
Cc: Dmitry Vyukov 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
[bwh: Backported to 3.16 in preparation for commit 017b1660df89
 "mm: migration: fix migration of huge PMD shared pages"]
Signed-off-by: Ben Hutchings

mm: replace remap_file_pages() syscall with emulation

2018-10-03T03:09:50+00:00

commit c8d78c1823f46519473949d33f0d1d33fe21ea16 upstream.

remap_file_pages(2) was invented to be able efficiently map parts of
huge file into limited 32-bit virtual address space such as in database
workloads.

Nonlinear mappings are pain to support and it seems there's no
legitimate use-cases nowadays since 64-bit systems are widely available.

Let's drop it and get rid of all these special-cased code.

The patch replaces the syscall with emulation which creates new VMA on
each remap_file_pages(), unless they it can be merged with an adjacent
one.

I didn't find *any* real code that uses remap_file_pages(2) to test
emulation impact on.  I've checked Debian code search and source of all
packages in ALT Linux.  No real users: libc wrappers, mentions in
strace, gdb, valgrind and this kind of stuff.

There are few basic tests in LTP for the syscall.  They work just fine
with emulation.

To test performance impact, I've written small test case which
demonstrate pretty much worst case scenario: map 4G shmfs file, write to
begin of every page pgoff of the page, remap pages in reverse order,
read every page.

The test creates 1 million of VMAs if emulation is in use, so I had to
set vm.max_map_count to 1100000 to avoid -ENOMEM.

Before:		23.3 ( +-  4.31% ) seconds
After:		43.9 ( +-  0.85% ) seconds
Slowdown:	1.88x

I believe we can live with that.

Test case:

        #define _GNU_SOURCE
        #include 
        #include 
        #include 
        #include 

        #define MB	(1024UL * 1024)
        #define SIZE	(4096 * MB)

        int main(int argc, char **argv)
        {
                unsigned long *p;
                long i, pass;

                for (pass = 0; pass < 10; pass++) {
                        p = mmap(NULL, SIZE, PROT_READ|PROT_WRITE,
                                        MAP_SHARED | MAP_ANONYMOUS, -1, 0);
                        if (p == MAP_FAILED) {
                                perror("mmap");
                                return -1;
                        }

                        for (i = 0; i < SIZE / 4096; i++)
                                p[i * 4096 / sizeof(*p)] = i;

                        for (i = 0; i < SIZE / 4096; i++) {
                                if (remap_file_pages(p + i * 4096 / sizeof(*p), 4096,
                                                0, (SIZE - 4096 * (i + 1)) >> 12, 0)) {
                                        perror("remap_file_pages");
                                        return -1;
                                }
                        }

                        for (i = SIZE / 4096 - 1; i >= 0; i--)
                                assert(p[i * 4096 / sizeof(*p)] == SIZE / 4096 - i - 1);

                        munmap(p, SIZE);
                }

                return 0;
        }

[akpm@linux-foundation.org: fix spello]
[sasha.levin@oracle.com: initialize populate before usage]
[sasha.levin@oracle.com: grab file ref to prevent race while mmaping]
Signed-off-by: "Kirill A. Shutemov" 
Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Dave Jones 
Cc: Linus Torvalds 
Cc: Armin Rigo 
Signed-off-by: Sasha Levin 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
[bwh: Backported to 3.16:
 - Deleted code is slightly different
 - Adjust context]
Signed-off-by: Ben Hutchings

mm: mark remap_file_pages() syscall as deprecated

2014-06-06T23:08:17+00:00

The remap_file_pages() system call is used to create a nonlinear
mapping, that is, a mapping in which the pages of the file are mapped
into a nonsequential order in memory.  The advantage of using
remap_file_pages() over using repeated calls to mmap(2) is that the
former approach does not require the kernel to create additional VMA
(Virtual Memory Area) data structures.

Supporting of nonlinear mapping requires significant amount of
non-trivial code in kernel virtual memory subsystem including hot paths.
Also to get nonlinear mapping work kernel need a way to distinguish
normal page table entries from entries with file offset (pte_file).
Kernel reserves flag in PTE for this purpose.  PTE flags are scarce
resource especially on some CPU architectures.  It would be nice to free
up the flag for other usage.

Fortunately, there are not many users of remap_file_pages() in the wild.
It's only known that one enterprise RDBMS implementation uses the
syscall on 32-bit systems to map files bigger than can linearly fit into
32-bit virtual address space.  This use-case is not critical anymore
since 64-bit systems are widely available.

The plan is to deprecate the syscall and replace it with an emulation.
The emulation will create new VMAs instead of nonlinear mappings.  It's
going to work slower for rare users of remap_file_pages() but ABI is
preserved.

One side effect of emulation (apart from performance) is that user can
hit vm.max_map_count limit more easily due to additional VMAs.  See
comment for DEFAULT_MAX_MAP_COUNT for more details on the limit.

[akpm@linux-foundation.org: fix spello]
Signed-off-by: Kirill A. Shutemov 
Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Dave Jones 
Cc: Armin Rigo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memory-failure.c: support use of a dedicated thread to handle SIGBUS(BUS_MCEERR_AO)

2014-06-04T23:54:13+00:00

Currently memory error handler handles action optional errors in the
deferred manner by default.  And if a recovery aware application wants
to handle it immediately, it can do it by setting PF_MCE_EARLY flag.
However, such signal can be sent only to the main thread, so it's
problematic if the application wants to have a dedicated thread to
handler such signals.

So this patch adds dedicated thread support to memory error handler.  We
have PF_MCE_EARLY flags for each thread separately, so with this patch
AO signal is sent to the thread with PF_MCE_EARLY flag set, not the main
thread.  If you want to implement a dedicated thread, you call prctl()
to set PF_MCE_EARLY on the thread.

Memory error handler collects processes to be killed, so this patch lets
it check PF_MCE_EARLY flag on each thread in the collecting routines.

No behavioral change for all non-early kill cases.

Tony said:

: The old behavior was crazy - someone with a multithreaded process might
: well expect that if they call prctl(PF_MCE_EARLY) in just one thread, then
: that thread would see the SIGBUS with si_code = BUS_MCEERR_A0 - even if
: that thread wasn't the main thread for the process.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Naoya Horiguchi 
Reviewed-by: Tony Luck 
Cc: Kamil Iskra 
Cc: Andi Kleen 
Cc: Borislav Petkov 
Cc: Chen Gong 
Cc: 	[3.2+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next

2014-06-04T15:50:34+00:00

Pull trivial tree changes from Jiri Kosina:
 "Usual pile of patches from trivial tree that make the world go round"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  staging: go7007: remove reference to CONFIG_KMOD
  aic7xxx: Remove obsolete preprocessor define
  of: dma: doc fixes
  doc: fix incorrect formula to calculate CommitLimit value
  doc: Note need of bc in the kernel build from 3.10 onwards
  mm: Fix printk typo in dmapool.c
  modpost: Fix comment typo "Modules.symvers"
  Kconfig.debug: Grammar s/addition/additional/
  wimax: Spelling s/than/that/, wording s/destinatary/recipient/
  aic7xxx: Spelling s/termnation/termination/
  arm64: mm: Remove superfluous "the" in comment
  of: Spelling s/anonymouns/anonymous/
  dma: imx-sdma: Spelling s/determnine/determine/
  ath10k: Improve grammar in comments
  ath6kl: Spelling s/determnine/determine/
  of: Improve grammar for of_alias_get_id() documentation
  drm/exynos: Spelling s/contro/control/
  radio-bcm2048.c: fix wrong overflow check
  doc: printk-formats: do not mention casts for u64/s64
  doc: spelling error changes
  ...

doc: spelling error changes

2014-05-05T13:32:05+00:00

Fixed multiple spelling errors.

Acked-by: Randy Dunlap 
Signed-off-by: Carlos E. Garcia 
Signed-off-by: Jiri Kosina

Documentation/vm/numa_memory_policy.txt: fix wrong document in numa_memory_policy.txt

2014-04-18T23:40:08+00:00

In document numa_memory_policy.txt, the following examples for flag
MPOL_F_RELATIVE_NODES are incorrect.

	For example, consider a task that is attached to a cpuset with
	mems 2-5 that sets an Interleave policy over the same set with
	MPOL_F_RELATIVE_NODES.  If the cpuset's mems change to 3-7, the
	interleave now occurs over nodes 3,5-6.  If the cpuset's mems
	then change to 0,2-3,5, then the interleave occurs over nodes
	0,3,5.

According to the comment of the patch adding flag MPOL_F_RELATIVE_NODES,
the nodemasks the user specifies should be considered relative to the
current task's mems_allowed.

 (https://lkml.org/lkml/2008/2/29/428)

And according to numa_memory_policy.txt, if the user's nodemask includes
nodes that are outside the range of the new set of allowed nodes, then
the remap wraps around to the beginning of the nodemask and, if not
already set, sets the node in the mempolicy nodemask.

So in the example, if the user specifies 2-5, for a task whose
mems_allowed is 3-7, the nodemasks should be remapped the third, fourth,
fifth, sixth node in mems_allowed.  like the following:

	mems_allowed:       3  4  5  6  7

	relative index:     0  1  2  3  4
	                    5

So the nodemasks should be remapped to 3,5-7, but not 3,5-6.

And for a task whose mems_allowed is 0,2-3,5, the nodemasks should be
remapped to 0,2-3,5, but not 0,3,5.

	mems_allowed:       0  2  3  5

        relative index:     0  1  2  3
                            4  5

Signed-off-by: Tang Chen 
Cc: Randy Dunlap 
Acked-by: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

doc: fix double words

2014-03-21T12:16:58+00:00

Fix double words "the the" in various files
within Documentations.

Signed-off-by: Masanari Iida 
Signed-off-by: Jiri Kosina

Documentation/: update 00-INDEX files

2014-02-11T00:01:40+00:00

Some of the 00-INDEX files are somewhat outdated and some folders does
not contain 00-INDEX at all.  Only outdated (with the notably exception
of spi) indexes are touched here, the 169 folders without 00-INDEX has
not been touched.

New 00-INDEX
 - spi/* was added in a series of commits dating back to 2006

Added files (missing in (*/)00-INDEX)
 - dmatest.txt was added by commit 851b7e16a07d ("dmatest: run test via
   debugfs")
 - this_cpu_ops.txt was added by commit a1b2a555d637 ("percpu: add
   documentation on this_cpu operations")
 - ww-mutex-design.txt was added by commit 040a0a371005 ("mutex: Add
   support for wound/wait style locks")
 - bcache.txt was added by commit cafe56359144 ("bcache: A block layer
   cache")
 - kernel-per-CPU-kthreads.txt was added by commit 49717cb40410
   ("kthread: Document ways of reducing OS jitter due to per-CPU
   kthreads")
 - phy.txt was added by commit ff764963479a ("drivers: phy: add generic
   PHY framework")
 - block/null_blk was added by commit 12f8f4fc0314 ("null_blk:
   documentation")
 - module-signing.txt was added by commit 3cafea307642 ("Add
   Documentation/module-signing.txt file")
 - assoc_array.txt was added by commit 3cb989501c26 ("Add a generic
   associative array implementation.")
 - arm/IXP4xx was part of the initial repo
 - arm/cluster-pm-race-avoidance.txt was added by commit 7fe31d28e839
   ("ARM: mcpm: introduce helpers for platform coherency exit/setup")
 - arm/firmware.txt was added by commit 7366b92a77fc ("ARM: Add
   interface for registering and calling firmware-specific operations")
 - arm/kernel_mode_neon.txt was added by commit 2afd0a05241d ("ARM:
   7825/1: document the use of NEON in kernel mode")
 - arm/tcm.txt was added by commit bc581770cfdd ("ARM: 5580/2: ARM TCM
   (Tightly-Coupled Memory) support v3")
 - arm/vlocks.txt was added by commit 9762f12d3e05 ("ARM: mcpm: Add
   baremetal voting mutexes")
 - blackfin/gptimers-example.c, Makefile was added by commit
   4b60779d5ea7 ("Blackfin: add an example showing how to use the
   gptimers API")
 - devicetree/usage-model.txt was added by commit 31134efc681a ("dt:
   Linux DT usage model documentation")
 - fb/api.txt was added by commit fb21c2f42879 ("fbdev: Add FOURCC-based
   format configuration API")
 - fb/sm501.txt was added by commit e6a049807105 ("video, sm501: add
   edid and commandline support")
 - fb/udlfb.txt was added by commit 96f8d864afd6 ("fbdev: move udlfb out
   of staging.")
 - filesystems/Makefile was added by commit 1e0051ae48a2
   ("Documentation/fs/: split txt and source files")
 - filesystems/nfs/nfsd-admin-interfaces.txt was added by commit
   8a4c6e19cfed ("nfsd: document kernel interfaces for nfsd
   configuration")
 - ide/warm-plug-howto.txt was added by commit f74c91413ec6 ("ide: add
   warm-plug support for IDE devices (take 2)")
 - laptops/Makefile was added by commit d49129accc21
   ("Documentation/laptop/: split txt and source files")
 - leds/leds-blinkm.txt was added by commit b54cf35a7f65 ("LEDS: add
   BlinkM RGB LED driver, documentation and update MAINTAINERS")
 - leds/ledtrig-oneshot.txt was added by commit 5e417281cde2 ("leds: add
   oneshot trigger")
 - leds/ledtrig-transient.txt was added by commit 44e1e9f8e705 ("leds:
   add new transient trigger for one shot timer activation")
 - m68k/README.buddha was part of the initial repo
 - networking/LICENSE.(qla3xxx|qlcnic|qlge) was added by commits
   40839129f779, c4e84bde1d59, 5a4faa873782
 - networking/Makefile was added by commit 3794f3e812ef ("docsrc: build
   Documentation/ sources")
 - networking/i40evf.txt was added by commit 105bf2fe6b32 ("i40evf: add
   driver to kernel build system")
 - networking/ipsec.txt was added by commit b3c6efbc36e2 ("xfrm: Add
   file to document IPsec corner case")
 - networking/mac80211-auth-assoc-deauth.txt was added by commit
   3cd7920a2be8 ("mac80211: add auth/assoc/deauth flow diagram")
 - networking/netlink_mmap.txt was added by commit 5683264c3981
   ("netlink: add documentation for memory mapped I/O")
 - networking/nf_conntrack-sysctl.txt was added by commit c9f9e0e1597f
   ("netfilter: doc: add nf_conntrack sysctl api documentation") lan)
 - networking/team.txt was added by commit 3d249d4ca7d0 ("net: introduce
   ethernet teaming device")
 - networking/vxlan.txt was added by commit d342894c5d2f ("vxlan:
   virtual extensible lan")
 - power/runtime_pm.txt was added by commit 5e928f77a09a ("PM: Introduce
   core framework for run-time PM of I/O devices (rev.  17)")
 - power/charger-manager.txt was added by commit 3bb3dbbd56ea
   ("power_supply: Add initial Charger-Manager driver")
 - RCU/lockdep-splat.txt was added by commit d7bd2d68aa2e ("rcu:
   Document interpretation of RCU-lockdep splats")
 - s390/kvm.txt was added by 5ecee4b (KVM: s390: API documentation)
 - s390/qeth.txt was added by commit b4d72c08b358 ("qeth: bridgeport
   support - basic control")
 - scheduler/sched-bwc.txt was added by commit 88ebc08ea9f7 ("sched: Add
   documentation for bandwidth control")
 - scsi/advansys.txt was added by commit 4bd6d7f35661 ("[SCSI] advansys:
   Move documentation to Documentation/scsi")
 - scsi/bfa.txt was added by commit 1ec90174bdb4 ("[SCSI] bfa: add
   readme file")
 - scsi/bnx2fc.txt was added by commit 12b8fc10eaf4 ("[SCSI] bnx2fc: Add
   driver documentation")
 - scsi/cxgb3i.txt was added by commit c3673464ebc0 ("[SCSI] cxgb3i: Add
   cxgb3i iSCSI driver.")
 - scsi/hpsa.txt was added by commit 992ebcf14f3c ("[SCSI] hpsa: Add
   hpsa.txt to Documentation/scsi")
 - scsi/link_power_management_policy.txt was added by commit
   ca77329fb713 ("[libata] Link power management infrastructure")
 - scsi/osd.txt was added by commit 78e0c621deca ("[SCSI] osd:
   Documentation for OSD library")
 - scsi/scsi-parameter.txt was created/moved by commit 163475fb111c
   ("Documentation: move SCSI parameters to their own text file")
 - serial/driver was part of the initial repo
 - serial/n_gsm.txt was added by commit 323e84122ec6 ("n_gsm: add a
   documentation")
 - timers/Makefile was added by commit 3794f3e812ef ("docsrc: build
   Documentation/ sources")
 - virt/kvm/s390.txt was added by commit d9101fca3d57 ("KVM: s390:
   diagnose call documentation")
 - vm/split_page_table_lock was added by commit 49076ec2ccaf ("mm:
   dynamically allocate page->ptl if it cannot be embedded to struct
   page")
 - w1/slaves/w1_ds28e04 was added by commit fbf7f7b4e2ae ("w1: Add
   1-wire slave device driver for DS28E04-100")
 - w1/masters/omap-hdq was added by commit e0a29382c6f5 ("hdq:
   documentation for OMAP HDQ")
 - x86/early-microcode.txt was added by commit 0d91ea86a895 ("x86, doc:
   Documentation for early microcode loading")
 - x86/earlyprintk.txt was added by commit a1aade478862 ("x86/doc:
   mini-howto for using earlyprintk=dbgp")
 - x86/entry_64.txt was added by commit 8b4777a4b50c ("x86-64: Document
   some of entry_64.S")
 - x86/pat.txt was added by commit d27554d874c7 ("x86: PAT
   documentation")

Moved files
 - arm/kernel_user_helpers.txt was moved out of arch/arm/kernel by
   commit 37b8304642c7 ("ARM: kuser: move interface documentation out of
   the source code")
 - efi-stub.txt was moved out of x86/ and down into Documentation/ in
   commit 4172fe2f8a47 ("EFI stub documentation updates")
 - laptops/hpfall.c was moved out of hwmon/ and into laptops/ in commit
   efcfed9bad88 ("Move hp_accel to drivers/platform/x86")
 - commit 5616c23ad9cd ("x86: doc: move x86-generic documentation from
   Doc/x86/i386"):
   * x86/usb-legacy-support.txt
   * x86/boot.txt
   * x86/zero_page.txt
 - power/video_extension.txt was moved to acpi in commit 70e66e4df191
   ("ACPI / video: move video_extension.txt to Documentation/acpi")

Removed files (left in 00-INDEX)
 - memory.txt was removed by commit 00ea8990aadf ("memory.txt: remove
   stray information")
 - gpio.txt was moved to gpio/ in commit fd8e198cfcaa ("Documentation:
   gpiolib: document new interface")
 - networking/DLINK.txt was removed by commit 168e06ae26dd
   ("drivers/net: delete old parallel port de600/de620 drivers")
 - serial/hayes-esp.txt was removed by commit f53a2ade0bb9 ("tty: esp:
   remove broken driver")
 - s390/TAPE was removed by commit 9e280f669308 ("[S390] remove tape
   block docu")
 - vm/locking was removed by commit 57ea8171d2bc ("mm: documentation:
   remove hopelessly out-of-date locking doc")
 - laptops/acer-wmi.txt was remvoed by commit 020036678e81 ("acer-wmi:
   Delete out-of-date documentation")

Typos/misc issues
 - rpc-server-gss.txt was added as knfsd-rpcgss.txt in commit
   030d794bf498 ("SUNRPC: Use gssproxy upcall for server RPCGSS
   authentication.")
 - commit b88cf73d9278 ("net: add missing entries to
   Documentation/networking/00-INDEX")
   * generic-hdlc.txt was added as generic_hdlc.txt
   * spider_net.txt was added as spider-net.txt
 - w1/master/mxc-w1 was added as mxc_w1 by commit a5fd9139f74c ("w1: add
   1-wire master driver for i.MX27 / i.MX31")
 - s390/zfcpdump.txt was added as zfcpdump by commit 6920c12a407e
   ("[S390] Add Documentation/s390/00-INDEX.")

Signed-off-by: Henrik Austad 
Reviewed-by: Paul E. McKenney 	[rcu bits]
Acked-by: Rob Landley 
Cc: Jiri Kosina 
Cc: Thomas Gleixner 
Cc: Rob Herring 
Cc: David S. Miller 
Cc: Mark Brown 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Gleb Natapov 
Cc: Linus Torvalds 
Cc: Len Brown 
Cc: James Bottomley 
Cc: Jean-Christophe Plagniol-Villard 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds