Pull locking fixes from Ingo Molnar:
 "Misc fixes:

   - Fix a S390 boot hang that was caused by the lock-break logic.
     Remove lock-break to begin with, as review suggested it was
     unreasonably fragile and our confidence in its continued good
     health is lower than our confidence in its removal.

   - Remove the lockdep cross-release checking code for now, because of
     unresolved false positive warnings. This should make lockdep work
     well everywhere again.

   - Get rid of the final (and single) ACCESS_ONCE() straggler and
     remove the API from v4.15.

   - Fix a liblockdep build warning"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/lib/lockdep: Add missing declaration of 'pr_cont()'
  checkpatch: Remove ACCESS_ONCE() warning
  compiler.h: Remove ACCESS_ONCE()
  tools/include: Remove ACCESS_ONCE()
  tools/perf: Convert ACCESS_ONCE() to READ_ONCE()
  locking/lockdep: Remove the cross-release locking checks
  locking/core: Remove break_lock field when CONFIG_GENERIC_LOCKBREAK=y
  locking/core: Fix deadlock during boot on systems with GENERIC_LOCKBREAK

Pull scheduler fixes from Ingo Molnar:
 "Two fixes: a crash fix for an ARM SoC platform, and kernel-doc
  warnings fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Do not pull from current CPU if only one CPU to pull
  sched/core: Fix kernel-doc warnings after code movement

Pull perf tooling fix from Ingo Molnar:
 "Synchronize kernel <-> tooling headers to resolve two build warnings
  in the perf build"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/headers: Synchronize kernel <-> tooling headers

Pull early_ioremap fix from Ingo Molnar:
 "A boot hang fix when the EFI earlyprintk driver is enabled"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep

Pull xen fixes from Juergen Gross:
 "Two minor fixes for running as Xen dom0:

   - when built as 32 bit kernel on large machines the Xen LAPIC
     emulation should report a rather modern LAPIC in order to support
     enough APIC-Ids

   - The Xen LAPIC emulation is needed for dom0 only, so build it only
     for kernels supporting to run as Xen dom0"

* tag 'for-linus-4.15-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: XEN_ACPI_PROCESSOR is Dom0-only
  x86/Xen: don't report ancient LAPIC version

Daniel Wagner reported a crash on the BeagleBone Black SoC.

This is a single CPU architecture, and does not have a functional
arch_send_call_function_single_ipi() implementation which can crash
the kernel if that is called.

As it only has one CPU, it shouldn't be called, but if the kernel is
compiled for SMP, the push/pull RT scheduling logic now calls it for
irq_work if the one CPU is overloaded, it can use that function to call
itself and crash the kernel.

Ideally, we should disable the SCHED_FEAT(RT_PUSH_IPI) if the system
only has a single CPU. But SCHED_FEAT is a constant if sched debugging
is turned off. Another fix can also be used, and this should also help
with normal SMP machines. That is, do not initiate the pull code if
there's only one RT overloaded CPU, and that CPU happens to be the
current CPU that is scheduling in a lower priority task.

Even on a system with many CPUs, if there's many RT tasks waiting to
run on a single CPU, and that CPU schedules in another RT task of lower
priority, it will initiate the PULL logic in case there's a higher
priority RT task on another CPU that is waiting to run. But if there is
no other CPU with waiting RT tasks, it will initiate the RT pull logic
on itself (as it still has RT tasks waiting to run). This is a wasted
effort.

Not only does this help with SMP code where the current CPU is the only
one with RT overloaded tasks, it should also solve the issue that
Daniel encountered, because it will prevent the PULL logic from
executing, as there's only one CPU on the system, and the check added
here will cause it to exit the RT pull code.
Reported-by: NDaniel Wagner <wagi@monom.org>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 4bdced5c ("sched/rt: Simplify the IPI based RT balancing logic")
Link: http://lkml.kernel.org/r/20171202130454.4cbbfe8d@vmware.local.homeSigned-off-by: NIngo Molnar <mingo@kernel.org>

Two kernel headers got modified recently, which are used by tooling as well:

 tools/include/uapi/linux/kvm.h
 arch/x86/include/asm/cpufeatures.h

None of those changes have an effect on tooling, so do a plain copy.

Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Pull power management fix from Rafael Wysocki:
 "This fixes an issue in two recent commits that may cause
  pm_runtime_enable() to be called for too many times for some devices
  during the "thaw" transition belonging to hibernation"

* tag 'pm-4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / sleep: Avoid excess pm_runtime_enable() calls in device_resume()

Pull tracing fixes from Steven Rostedt:
 "Various fix-ups:

   - comment fixes

   - build fix

   - better memory alloction (don't use NR_CPUS)

   - configuration fix

   - build warning fix

   - enhanced callback parameter (to simplify users of trace hooks)

   - give up on stack tracing when RCU isn't watching (it's a lost
     cause)"

* tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have stack trace not record if RCU is not watching
  tracing: Pass export pointer as argument to ->write()
  ring-buffer: Remove unused function __rb_data_page_index()
  tracing: make PREEMPTIRQ_EVENTS depend on TRACING
  tracing: Allocate mask_str buffer dynamically
  tracing: always define trace_{irq,preempt}_{enable_disable}
  tracing: Fix code comments in trace.c

The stack tracer records a stack dump whenever it sees a stack usage that is
more than what it ever saw before. This can happen at any function that is
being traced. If it happens when the CPU is going idle (or other strange
locations), RCU may not be watching, and in this case, the recording of the
stack trace will trigger a warning. There's been lots of efforts to make
hacks to allow stack tracing to proceed even if RCU is not watching, but
this only causes more issues to appear. Simply do not trace a stack if RCU
is not watching. It probably isn't a bad stack anyway.
Acked-by: N"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Pull PCI fixes from Bjorn Helgaas:

 - add a pci_get_domain_bus_and_slot() stub for the CONFIG_PCI=n case to
   avoid build breakage in the v4.16 merge window if a
   pci_get_bus_and_slot() -> pci_get_domain_bus_and_slot() patch gets
   merged before the PCI tree (Randy Dunlap)

 - fix an AMD boot regression in the 64bit BAR support added in v4.15
   (Christian König)

 - fix an R-Car use-after-free that causes a crash if no PCIe card is
   present (Geert Uytterhoeven)

* tag 'pci-v4.15-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: rcar: Fix use-after-free in probe error path
  x86/PCI: Only enable a 64bit BAR on single-socket AMD Family 15h
  x86/PCI: Fix infinite loop in search for 64bit BAR placement
  PCI: Add pci_get_domain_bus_and_slot() stub

Merge misc fixes from Andrew Morton:
 "17 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  arch: define weak abort()
  mm, oom_reaper: fix memory corruption
  kernel: make groups_sort calling a responsibility group_info allocators
  mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()'
  tools/slabinfo-gnuplot: force to use bash shell
  kcov: fix comparison callback signature
  mm/slab.c: do not hash pointers when debugging slab
  mm/page_alloc.c: avoid excessive IRQ disabled times in free_unref_page_list()
  mm/memory.c: mark wp_huge_pmd() inline to prevent build failure
  scripts/faddr2line: fix CROSS_COMPILE unset error
  Documentation/vm/zswap.txt: update with same-value filled page feature
  exec: avoid gcc-8 warning for get_task_comm
  autofs: fix careless error in recent commit
  string.h: workaround for increased stack usage
  mm/kmemleak.c: make cond_resched() rate-limiting more efficient
  lib/rbtree,drm/mm: add rbtree_replace_node_cached()
  include/linux/idr.h: add #include <linux/bug.h>

gcc toggle -fisolate-erroneous-paths-dereference (default at -O2
onwards) isolates faulty code paths such as null pointer access, divide
by zero etc.  If gcc port doesnt implement __builtin_trap, an abort() is
generated which causes kernel link error.

In this case, gcc is generating abort due to 'divide by zero' in
lib/mpi/mpih-div.c.

Currently 'frv' and 'arc' are failing.  Previously other arch was also
broken like m32r was fixed by commit d22e3d69 ("m32r: fix build
failure").

Let's define this weak function which is common for all arch and fix the
problem permanently.  We can even remove the arch specific 'abort' after
this is done.

Link: http://lkml.kernel.org/r/1513118956-8718-1-git-send-email-sudipm.mukherjee@gmail.comSigned-off-by: NSudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

David Rientjes has reported the following memory corruption while the
oom reaper tries to unmap the victims address space

  BUG: Bad page map in process oom_reaper  pte:6353826300000000 pmd:00000000
  addr:00007f50cab1d000 vm_flags:08100073 anon_vma:ffff9eea335603f0 mapping:          (null) index:7f50cab1d
  file:          (null) fault:          (null) mmap:          (null) readpage:          (null)
  CPU: 2 PID: 1001 Comm: oom_reaper
  Call Trace:
     unmap_page_range+0x1068/0x1130
     __oom_reap_task_mm+0xd5/0x16b
     oom_reaper+0xff/0x14c
     kthread+0xc1/0xe0

Tetsuo Handa has noticed that the synchronization inside exit_mmap is
insufficient.  We only synchronize with the oom reaper if
tsk_is_oom_victim which is not true if the final __mmput is called from
a different context than the oom victim exit path.  This can trivially
happen from context of any task which has grabbed mm reference (e.g.  to
read /proc/<pid>/ file which requires mm etc.).

The race would look like this

  oom_reaper		oom_victim		task
						mmget_not_zero
			do_exit
			  mmput
  __oom_reap_task_mm				mmput
  						  __mmput
						    exit_mmap
						      remove_vma
    unmap_page_range

Fix this issue by providing a new mm_is_oom_victim() helper which
operates on the mm struct rather than a task.  Any context which
operates on a remote mm struct should use this helper in place of
tsk_is_oom_victim.  The flag is set in mark_oom_victim and never cleared
so it is stable in the exit_mmap path.

Debugged by Tetsuo Handa.

Link: http://lkml.kernel.org/r/20171210095130.17110-1-mhocko@kernel.org
Fixes: 21292580 ("mm: oom: let oom_reap_task and exit_mmap run concurrently")
Signed-off-by: NMichal Hocko <mhocko@suse.com>
Reported-by: NDavid Rientjes <rientjes@google.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: <stable@vger.kernel.org>	[4.14]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.

This patch:
 - Make groups_sort globally visible.
 - Move the call to groups_sort to the modifiers of group_info
 - Remove the call to groups_sort from set_groups

Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.comSigned-off-by: NThiago Rafael Becker <thiago.becker@gmail.com>
Reviewed-by: NMatthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NNeilBrown <neilb@suse.com>
Acked-by: N"J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A semaphore is acquired before this check, so we must release it before
leaving.

Link: http://lkml.kernel.org/r/20171211211009.4971-1-christophe.jaillet@wanadoo.fr
Fixes: b7f0554a ("mm: fail get_vaddr_frames() for filesystem-dax mappings")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On some linux distributions, the default link of sh is dash which
deoesn't support split array like "${var//,/ }"

It's better to force to use bash shell directly.

Link: http://lkml.kernel.org/r/20171208093751.GA175471@sofiaSigned-off-by: NLiu Changcheng <changcheng.liu@intel.com>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix a silly copy-paste bug.  We truncated u32 args to u16.

Link: http://lkml.kernel.org/r/20171207101134.107168-1-dvyukov@google.com
Fixes: ded97d2c ("kcov: support comparison operands collection")
Signed-off-by: NDmitry Vyukov <dvyukov@google.com>
Cc: syzkaller@googlegroups.com
Cc: Alexander Potapenko <glider@google.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If CONFIG_DEBUG_SLAB/CONFIG_DEBUG_SLAB_LEAK are enabled, the slab code
prints extra debug information when e.g.  corruption is detected.  This
includes pointers, which are not very useful when hashed.

Fix this by using %px to print unhashed pointers instead where it makes
sense, and by removing the printing of a last user pointer referring to
code.

[geert+renesas@glider.be: v2]
  Link: http://lkml.kernel.org/r/1513179267-2509-1-git-send-email-geert+renesas@glider.be
Link: http://lkml.kernel.org/r/1512641861-5113-1-git-send-email-geert+renesas@glider.be
Fixes: ad67b74d ("printk: hash addresses printed with %p")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NChristoph Lameter <cl@linux.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Tobin C . Harding" <me@tobin.cc>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since commit 9cca35d4 ("mm, page_alloc: enable/disable IRQs once
when freeing a list of pages") we see excessive IRQ disabled times of up
to 25ms on an embedded ARM system (tracing overhead included).

This is due to graphics buffers being freed back to the system via
release_pages().  Graphics buffers can be huge, so it's not hard to hit
cases where the list of pages to free has 2048 entries.  Disabling IRQs
while freeing all those pages is clearly not a good idea.

Introduce a batch limit, which allows IRQ servicing once every few
pages.  The batch count is the same as used in other parts of the MM
subsystem when dealing with IRQ disabled regions.

Link: http://lkml.kernel.org/r/20171207170314.4419-1-l.stach@pengutronix.de
Fixes: 9cca35d4 ("mm, page_alloc: enable/disable IRQs once when freeing a list of pages")
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Acked-by: NMel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With gcc 4.1.2:

    mm/memory.o: In function `wp_huge_pmd':
    memory.c:(.text+0x9b4): undefined reference to `do_huge_pmd_wp_page'

Interestingly, wp_huge_pmd() is emitted in the assembler output, but
never called.

Apparently replacing the call to pmd_write() in __handle_mm_fault() by a
call to the more complex pmd_access_permitted() reduced the ability of
the compiler to remove unused code.

Fix this by marking wp_huge_pmd() inline, like was done in commit
91a90140 ("mm/memory.c: mark create_huge_pmd() inline to prevent
build failure") for a similar problem.

[akpm@linux-foundation.org: add comment]
Link: http://lkml.kernel.org/r/1512335500-10889-1-git-send-email-geert@linux-m68k.org
Fixes: c7da82b8 ("mm: replace pmd_write with pmd_access_permitted in fault + gup paths")
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

faddr2line hit var unbound error when CROSS_COMPILE isn't set since
nounset option is set in bash script.

Link: http://lkml.kernel.org/r/20171206013022.GA83929@sofia
Fixes: 95a87982 ("scripts/faddr2line: extend usage on generic arch")
Signed-off-by: NLiu Changcheng <changcheng.liu@intel.com>
Reported-by: NRichard Weinberger <richard.weinberger@gmail.com>
Reviewed-by: NRichard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Update zswap document with details on same-value filled pages
identification feature.  The usage of zswap.same_filled_pages_enabled
module parameter is explained.

Link: http://lkml.kernel.org/r/20171206114852epcms5p6973b02a9f455d5d3c765eafda0fe2631@epcms5p6Signed-off-by: NSrividya Desireddy <srividya.dr@samsung.com>
Acked-by: NDan Streetman <ddstreet@ieee.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

gcc-8 warns about using strncpy() with the source size as the limit:

  fs/exec.c:1223:32: error: argument to 'sizeof' in 'strncpy' call is the same expression as the source; did you mean to use the size of the destination? [-Werror=sizeof-pointer-memaccess]

This is indeed slightly suspicious, as it protects us from source
arguments without NUL-termination, but does not guarantee that the
destination is terminated.

This keeps the strncpy() to ensure we have properly padded target
buffer, but ensures that we use the correct length, by passing the
actual length of the destination buffer as well as adding a build-time
check to ensure it is exactly TASK_COMM_LEN.

There are only 23 callsites which I all reviewed to ensure this is
currently the case.  We could get away with doing only the check or
passing the right length, but it doesn't hurt to do both.

Link: http://lkml.kernel.org/r/20171205151724.1764896-1-arnd@arndb.deSigned-off-by: NArnd Bergmann <arnd@arndb.de>
Suggested-by: NKees Cook <keescook@chromium.org>
Acked-by: NKees Cook <keescook@chromium.org>
Acked-by: NIngo Molnar <mingo@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Aleksa Sarai <asarai@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit ecc0c469 ("autofs: don't fail mount for transient error") was
meant to replace an 'if' with a 'switch', but instead added the 'switch'
leaving the case in place.

Link: http://lkml.kernel.org/r/87zi6wstmw.fsf@notabene.neil.brown.name
Fixes: ecc0c469 ("autofs: don't fail mount for transient error")
Reported-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NNeilBrown <neilb@suse.com>
Cc: Ian Kent <raven@themaw.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The hardened strlen() function causes rather large stack usage in at
least one file in the kernel, in particular when CONFIG_KASAN is
enabled:

  drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init':
  drivers/media/usb/em28xx/em28xx-dvb.c:2062:1: error: the frame size of 3256 bytes is larger than 204 bytes [-Werror=frame-larger-than=]

Analyzing this problem led to the discovery that gcc fails to merge the
stack slots for the i2c_board_info[] structures after we strlcpy() into
them, due to the 'noreturn' attribute on the source string length check.

I reported this as a gcc bug, but it is unlikely to get fixed for gcc-8,
since it is relatively easy to work around, and it gets triggered
rarely.  An earlier workaround I did added an empty inline assembly
statement before the call to fortify_panic(), which works surprisingly
well, but is really ugly and unintuitive.

This is a new approach to the same problem, this time addressing it by
not calling the 'extern __real_strnlen()' function for string constants
where __builtin_strlen() is a compile-time constant and therefore known
to be safe.

We do this by checking if the last character in the string is a
compile-time constant '\0'.  If it is, we can assume that strlen() of
the string is also constant.

As a side-effect, this should also improve the object code output for
any other call of strlen() on a string constant.

[akpm@linux-foundation.org: add comment]
Link: http://lkml.kernel.org/r/20171205215143.3085755-1-arnd@arndb.de
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
Link: https://patchwork.kernel.org/patch/9980413/
Link: https://patchwork.kernel.org/patch/9974047/
Fixes: 6974f0c4 ("include/linux/string.h: add the option of fortified string.h functions")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Martin Wilck <mwilck@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit bde5f6bc ("kmemleak: add scheduling point to
kmemleak_scan()") tries to rate-limit the frequency of cond_resched()
calls, but does it in a way which might incur an expensive division
operation in the inner loop.  Simplify this.

Fixes: bde5f6bc ("kmemleak: add scheduling point to kmemleak_scan()")
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a variant of rbtree_replace_node() that maintains the leftmost cache
of struct rbtree_root_cached when replacing nodes within the rbtree.

As drm_mm is the only rb_replace_node() being used on an interval tree,
the mistake looks fairly self-contained.  Furthermore the only user of
drm_mm_replace_node() is its testsuite...

Testcase: igt/drm_mm/replace

Link: http://lkml.kernel.org/r/20171122100729.3742-1-chris@chris-wilson.co.uk
Link: https://patchwork.freedesktop.org/patch/msgid/20171109212435.9265-1-chris@chris-wilson.co.uk
Fixes: f808c13f ("lib/interval_tree: fast overlap detection")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: NDavidlohr Bueso <dbueso@suse.de>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The <linux/bug.h> was removed from radix-tree.h by commit f5bba9d1
("include/linux/radix-tree.h: remove unneeded #include <linux/bug.h>").

Since that commit, tools/testing/radix-tree/ couldn't pass compilation
due to tools/testing/radix-tree/idr.c:17: undefined reference to
WARN_ON_ONCE.  This patch adds the bug.h header to idr.h to solve the
issue.

Link: http://lkml.kernel.org/r/1511963726-34070-2-git-send-email-wei.w.wang@intel.com
Fixes: f5bba9d1 ("include/linux/radix-tree.h: remove unneeded #include <linux/bug.h>")
Signed-off-by: NWei Wang <wei.w.wang@intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull cifs fixes from Steve French:
 "Small SMB3 fixes for stable and 4.15rc"

* tag '4.15-rc-smb3' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: don't log STATUS_NOT_FOUND errors for DFS
  cifs: fix NULL deref in SMB2_read

Pull drm fixes from Daniel Vetter:

 - two fixes for new core features

 - a corner case fix for the connnector_iter fix from last week (this
   one is cc: stable)

 - one vc4 fix

* tag 'drm-misc-fixes-2017-12-14' of git://anongit.freedesktop.org/drm/drm-misc:
  drm/drm_lease: Prevent deadlock in case drm_lease_create() fails
  drm: rework delayed connector cleanup in connector_iter
  drm: Update edid-derived drm_display_info fields at edid property set [v2]
  drm/vc4: Release fence after signalling

This case can been seen when creating the lease with the same objects passed.

[  605.515097] 2 locks held by testapp/3337:
[  605.519027]  #0:  (&dev->mode_config.idr_mutex){......}, at: [<ffff0000085f1664>] drm_mode_create_lease_ioctl+0x384/0x858
[  605.530045]  #1:  (&dev->mode_config.idr_mutex){......}, at: [<ffff0000085f11bc>] drm_lease_destroy+0x2c/0x110

Which was causing the process to hang:

[  605.398827] [<ffff0000080856cc>] __switch_to+0x94/0xa8
[  605.404030] [<ffff000008c05d00>] __schedule+0x1b0/0x698
[  605.409322] [<ffff000008c06224>] schedule+0x3c/0xa8
[  605.414260] [<ffff000008c06628>] schedule_preempt_disabled+0x20/0x38
[  605.420677] [<ffff000008c07370>] mutex_lock_nested+0x158/0x340
[  605.426572] [<ffff0000085f11bc>] drm_lease_destroy+0x2c/0x110
[  605.432389] [<ffff0000085cecf0>] drm_master_put+0xc0/0xc8
[  605.437845] [<ffff0000085f175c>] drm_mode_create_lease_ioctl+0x47c/0x858
[  605.444612] [<ffff0000085d4460>] drm_ioctl+0x198/0x448
[  605.449811] [<ffff000008201134>] do_vfs_ioctl+0xa4/0x748
[  605.455192] [<ffff000008201864>] SyS_ioctl+0x8c/0xa0
[  605.460216] [<ffff000008082f4c>] __sys_trace_return+0x0/0x4

drm_mode_create_lease_ioctl() calls drm_lease_create() which acquires a lock
on dev->mode_config.idr_mutex. In case of failure, drm_lease_create() calls
drm_master_put() which in turn tries to acquire the same lock when calling
drm_lease_destroy().

v2: - Reverse the order at exit in case of fail, so that unlocking takes place
before dropping the reference.
    - Include detail information about deadlock (Daniel Vetter)
Signed-off-by: NMarius Vlad <marius-cristian.vlad@nxp.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171213181048.32719-1-marius-cristian.vlad@nxp.com

Pull xfs fixes from Darrick Wong:
 "Here are a few more bug fixes & cleanups for 4.15-rc4:

   - clean up duplicate includes

   - remove ancient 'no-alloc' crap code that occasionally caused hard
     fs shutdowns due to lack of proper space reservations

   - fix regression in FIEMAP behavior when reporting xattr extents"

* tag 'xfs-4.15-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: make iomap_begin functions trim iomaps consistently
  xfs: remove "no-allocation" reservations for file creations
  fs: xfs: remove duplicate includes

Merge tag 'riscv-for-linus-4.15-rc4-riscv_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux

Pull RISC-V fixes from Palmer Dabbelt:
 "This contains three small fixes:

   - A fix to a typo in sys_riscv_flush_icache. This only effects error
     handling, but I think it's a small and obvious enough change that
     it's sane outside the merge window.

   - The addition of smp_mb__after_spinlock(), which was recently
     removed due to an incorrect comment. This is largly a comment
     change (as there's a big one now), and while it's necessary for
     complience with the RISC-V memory model the lack of this fence
     shouldn't manifest as a bug on current implementations.
     Nonetheless, it still seems saner to have the fence in 4.15.

   - The removal of some of the HVC_RISCV_SBI driver that snuck into the
     arch port. This is compile-time dead code in 4.15 (as the driver
     isn't in yet), and during the review process we found a better way
     to implement early printk on RISC-V. While this change doesn't do
     anything, it will make staging our HVC driver easier: without this
     change the HVC driver we hope to upstream won't build on 4.15
     (because the 4.15 arch code would reference a function that no
     longer exists).

  I don't think this is the last patch set we'll want for 4.15: I think
  I'll want to remove some of the first-level irqchip driver that snuck
  in as well, which will look a lot like the HVC patch here. This is
  pending some asm-generic cleanup I'm doing that I haven't quite gotten
  clean enough to send out yet, though, but hopefully it'll be ready by
  next week (and still OK for that late)"

 * tag 'riscv-for-linus-4.15-rc4-riscv_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux:
  RISC-V: Remove unused CONFIG_HVC_RISCV_SBI code
  RISC-V: Resurrect smp_mb__after_spinlock()
  RISC-V: Logical vs Bitwise typo

PROBE_DEFER also uses system_wq to reprobe drivers, which means when
that again fails, and we try to flush the overall system_wq (to get
all the delayed connectore cleanup work_struct completed), we
deadlock.

Fix this by using just a single cleanup work, so that we can only
flush that one and don't block on anything else. That means a free
list plus locking, a standard pattern.

v2:
- Correctly free connectors only on last ref. Oops (Chris).
- use llist_head/node (Chris).

v3
- Add init_llist_head (Chris).

Fixes: a703c550 ("drm: safely free connectors from connector_iter")
Fixes: 613051da ("drm: locking&new iterators for connector_list")
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: <stable@vger.kernel.org> # v4.11+: 613051da ("drm: locking&new iterators for connector_list"
Cc: <stable@vger.kernel.org> # v4.11+
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Javier Martinez Canillas <javier@dowhile0.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Guillaume Tucker <guillaume.tucker@collabora.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Matt Hart <matthew.hart@linaro.org>
Cc: Thierry Escande <thierry.escande@collabora.co.uk>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171213124936.17914-1-daniel.vetter@ffwll.ch

There are a set of values in the drm_display_info structure for each
connector which hold information derived from EDID. These are computed
in drm_add_display_info. Before this patch, that was only called in
drm_add_edid_modes. This meant that they were only set when EDID was
present and never reset when EDID was not, as happened when the
display was disconnected.

One of these fields, non_desktop, is used from
drm_mode_connector_update_edid_property, the function responsible for
assigning the new edid value to the application-visible property.

Various drivers call these two functions (drm_add_edid_modes and
drm_mode_connector_update_edid_property) in different orders. This
means that even when EDID is present, the drm_display_info fields may
not have been computed at the time that
drm_mode_connector_update_edid_property used the non_desktop value to
set the non_desktop property.

I've added a public function (drm_reset_display_info) that resets the
drm_display_info field values to default values and then made the
drm_add_display_info function public. These two functions are now
called directly from drm_mode_connector_update_edid_property so that
the drm_display_info fields are always computed from the current EDID
information before being used in that function.

This means that the drm_display_info values are often computed twice,
once when the EDID property it set and a second time when EDID is used
to compute modes for the device. The alternative would be to uniformly
ensure that the values were computed once before being used, which
would require that all drivers reliably invoke the two paths in the
same order. The computation is inexpensive enough that it seems more
maintainable in the long term to simply compute them in both paths.

The API to drm_add_display_info has been changed so that it no longer
takes the set of edid-based quirks as a parameter. Rather, it now
computes those quirks itself and returns them for further use by
drm_add_edid_modes.

This patch also includes a number of 'const' additions caused by
drm_mode_connector_update_edid_property taking a 'const struct edid *'
parameter and wanting to pass that along to drm_add_display_info.

v2: after review by Daniel Vetter <daniel.vetter@ffwll.ch>

	Removed EXPORT_SYMBOL_GPL for drm_reset_display_info and
	drm_add_display_info.

	Added FIXME in drm_mode_connector_update_edid_property about
	potentially merging that with drm_add_edid_modes to avoid
	the need for two driver calls.
Signed-off-by: NKeith Packard <keithp@keithp.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171213084427.31199-1-keithp@keithp.com
(danvet: cherry picked from commit 12a889bf4bca ("drm: rework delayed
connector cleanup in connector_iter") from drm-misc-next since
functional conflict with changes in -next and we need to make sure
both have the right version and nothing gets lost.)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Commit:

  681fbec8 ("lockdep: Use consistent printing primitives")

has moved lockdep away from using printk() for printing.

The commit added usage of pr_cont() which wasn't wrapped in the
userspace headers, causing the following warning for the
liblockdep build:

	../../../kernel/locking/lockdep.c:3544:2: warning: implicit declaration of function 'pr_cont' [-Wimplicit-function-declaration]

Adding an empty declaration of 'pr_cont' fixes the problem.
Signed-off-by: NMengting Zhang <zhangmengting@huawei.com>
Signed-off-by: NSasha Levin <alexander.levin@verizon.com>
Reviewed-by: NAlexander Sverdlin <alexander.sverdlin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/20171212181644.11913-2-alexander.levin@verizon.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Pull x86 platform driver fixes from Darren Hart:

 - Correct an error in the evdev protocol in asus-wireless which results
   in dropped key events in recent versions of libinput

 - Add a quirk for keyboard lighting for a specific Dell laptop

 - Silence a static analysis warning regarding unchecked return values
   of small kmalloc() allocations in dell-wmi

* tag 'platform-drivers-x86-v4.15-3' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: dell-wmi: check for kmalloc() errors
  platform/x86: asus-wireless: send an EV_SYN/SYN_REPORT between state changes
  platform/x86: dell-laptop: Fix keyboard max lighting for Dell Latitude E6410

If CONFIG_DEBUG_SLAB=y, and no PCIe card is inserted, the kernel crashes
during probe on r8a7791/koelsch:

  rcar-pcie fe000000.pcie: PCIe link down
  Unable to handle kernel paging request at virtual address 6b6b6b6b

(seeing this message requires earlycon and keep_bootcon).

Indeed, pci_free_host_bridge() frees the PCI host bridge, including the
embedded rcar_pcie object, so pci_free_resource_list() must not be called
afterwards.

To fix this, move the call to pci_free_resource_list() up, and update the
label name accordingly.

Fixes: ddd535f1 ("PCI: rcar: Fix memory leak when no PCIe card is inserted")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Acked-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Add a respective dependency.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Reviewed-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>