There are 11 interpretations of the requirements described in the header
comment for smp_mb__after_spinlock(): one for each LKMM maintainer, and
one currently encoded in the Cat file. Stick to the latter (until a more
satisfactory solution is available).

This also reworks some snippets related to the barrier to illustrate the
requirements and to link them to the idioms which are relied upon at its
call sites.
Suggested-by: NBoqun Feng <boqun.feng@gmail.com>
Signed-off-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: akiyks@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Link: http://lkml.kernel.org/r/20180716180605.16115-11-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

wake_woken_function() synchronizes with wait_woken() as follows:

  [wait_woken]                       [wake_woken_function]

  entry->flags &= ~wq_flag_woken;    condition = true;
  smp_mb();                          smp_wmb();
  if (condition)                     wq_entry->flags |= wq_flag_woken;
     break;

This commit replaces the above smp_wmb() with an smp_mb() in order to
guarantee that either wait_woken() sees the wait condition being true
or the store to wq_entry->flags in woken_wake_function() follows the
store in wait_woken() in the coherence order (so that the former can
eventually be observed by wait_woken()).

The commit also fixes a comment associated to set_current_state() in
wait_woken(): the comment pairs the barrier in set_current_state() to
the above smp_wmb(), while the actual pairing involves the barrier in
set_current_state() and the barrier executed by the try_to_wake_up()
in wake_woken_function().
Signed-off-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-10-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The Linux-kernel memory model has been informal, with a number of
text files documenting it.  It would be good to make sure that these
informal descriptions are kept up to date and/or pruned appropriately.
This commit therefore brings more of those text files into the LKMM
MAINTAINERS file entry.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: parri.andrea@gmail.com
Link: http://lkml.kernel.org/r/20180716180605.16115-9-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The atomic_set() and ATOMIC_INIT() operations are writes, so this
commit changes their description from "reads" to "writes".
Signed-off-by: NJonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-8-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This commit makes the scripts executable to avoid the need for everyone
to do so manually in their archive.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NAkira Yokosawa <akiyks@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-7-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Since commit:

  b899a850 ("compiler.h: Remove ACCESS_ONCE()")

... there has been no definition of ACCESS_ONCE() in the kernel tree,
and it has been necessary to use READ_ONCE() or WRITE_ONCE() instead.

Correspondingly, let's remove ACCESS_ONCE() from the kernel memory
model.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: parri.andrea@gmail.com
Link: http://lkml.kernel.org/r/20180716180605.16115-6-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Since commit:

  b899a850 ("compiler.h: Remove ACCESS_ONCE()")

... there has been no definition of ACCESS_ONCE() in the kernel tree,
and it has been necessary to use READ_ONCE() or WRITE_ONCE() instead.

Let's update the exmaples in recipes.txt likewise for consistency, using
READ_ONCE() for reads.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: parri.andrea@gmail.com
Link: http://lkml.kernel.org/r/20180716180605.16115-5-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

locking/memory-barriers.txt/kokr: Update Korean translation to fix broken DMA vs. MMIO ordering example

Translate this commit to Korean:

  5846581e ("locking/memory-barriers.txt: Fix broken DMA vs. MMIO ordering example")

[ paulmck: Updated based on feedback from Byungchul Park. ]
Signed-off-by: NSeongJae Park <sj38.park@gmail.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NByungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-4-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Dan runs the RISC-V memory model working group.  I've been forwarding
him LKMM emails that end up in my inbox, but I'm far from an expert in
this stuff.  He requested to be added as a reviewer, which seems sane to
me as it'll take a human out of the loop.
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDaniel Lustig <dlustig@nvidia.com>
Acked-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-3-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The names on the first line of the litmus tests are arbitrary,
but the convention is that they be the filename without the trailing
".litmus".  This commit therefore removes the stray trailing ".litmus"
from ISA2+pooncelock+pooncelock+pombonce.litmus's name.
Reported-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-2-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This commit adds a litmus test suggested by Alan Stern that is forbidden
on fully multicopy atomic systems, but allowed on other-multicopy and
on non-multicopy atomic systems.  For reference, s390 is fully multicopy
atomic, x86 and ARMv8 are other-multicopy atomic, and ARMv7 and powerpc
are non-multicopy atomic.
Suggested-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NAndrea Parri <andrea.parri@amarulasolutions.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20180716180605.16115-1-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NIngo Molnar <mingo@kernel.org>

Pull ARM SoC fixes from Olof Johansson:

 - A fix for OMAP5 and DRA7 to make the branch predictor hardening
   settings take proper effect on secondary cores

 - Disable USB OTG on am3517 since current driver isn't working

 - Fix thermal sensor register settings on Armada 38x

 - Fix suspend/resume IRQs on pxa3xx

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: dts: am3517.dtsi:  Disable reference to OMAP3 OTG controller
  ARM: DRA7/OMAP5: Enable ACTLR[0] (Enable invalidates of BTB) for secondary cores
  ARM: pxa: irq: fix handling of ICMR registers in suspend/resume
  ARM: dts: armada-38x: use the new thermal binding

Pull RTC fixes from Alexandre Belloni:
 "Two fixes for 4.18:

   - an important core fix for RTCs using the core offsetting only one
     driver is affected

   - a fix for the error path of mrst"

* tag 'rtc-4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  rtc: fix alarm read and set offset
  rtc: mrst: fix error code in probe()

Merge tag 'omap-for-v4.18/fixes-rc4-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Two omap fixes for v4.18-rc cycle

Turns out the recent patches for ARM branch predictor hardening are
not working on omap5 and dra7 as planned because the secondary CPU
is parked to the bootrom code. We can't configure it in the bootloader.
So we must enable invalidates of BTB for omap5 and dra7 secondary
core in the kernel.

And there's a fix for reserved register access for am3517. The
usb otg module on am3517 is not the same as for other omap3.

* tag 'omap-for-v4.18/fixes-rc4-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: am3517.dtsi:  Disable reference to OMAP3 OTG controller
  ARM: DRA7/OMAP5: Enable ACTLR[0] (Enable invalidates of BTB) for secondary cores
Signed-off-by: NOlof Johansson <olof@lixom.net>

mvebu fixes for 4.18 (part 1)

Use the new thermal binding on Armada 38x allowing to use a driver fix
which is already part of the kernel.

* tag 'mvebu-fixes-4.18-1' of git://git.infradead.org/linux-mvebu:
  ARM: dts: armada-38x: use the new thermal binding
Signed-off-by: NOlof Johansson <olof@lixom.net>

This is the fixes set for v4.18 cycle.

This is a fix for suspending all pxa3xx platforms, where high
number interrupts are not reenabled.

* tag 'pxa-fixes-4.18' of https://github.com/rjarzmik/linux:
  ARM: pxa: irq: fix handling of ICMR registers in suspend/resume
Signed-off-by: NOlof Johansson <olof@lixom.net>

Pull xen fixes from Juergen Gross:
 "Two related fixes for a boot failure of Xen PV guests"

* tag 'for-linus-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: setup pv irq ops vector earlier
  xen: remove global bit from __default_kernel_pte_mask for pv guests

Pull block fix from Jens Axboe:
 "Just a single regression fix (from 4.17) for bsg, fixing an EINVAL
  return on non-data commands"

* tag 'for-linus-20180713' of git://git.kernel.dk/linux-block:
  bsg: fix bogus EINVAL on non-data commands

Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches form Andrew Morton <akpm@linux-foundation.org>:
  reiserfs: fix buffer overflow with long warning messages
  checkpatch: fix duplicate invalid vsprintf pointer extension '%p<foo>' messages
  mm: do not bug_on on incorrect length in __mm_populate()
  mm/memblock.c: do not complain about top-down allocations for !MEMORY_HOTREMOVE
  fs, elf: make sure to page align bss in load_elf_library
  x86/purgatory: add missing FORCE to Makefile target
  net/9p/client.c: put refcount of trans_mod in error case in parse_opts()
  mm: allow arch to supply p??_free_tlb functions
  autofs: fix slab out of bounds read in getname_kernel()
  fs/proc/task_mmu.c: fix Locked field in /proc/pid/smaps*
  mm: do not drop unused pages when userfaultd is running

ReiserFS prepares log messages into a 1024-byte buffer with no bounds
checks.  Long messages, such as the "unknown mount option" warning when
userspace passes a crafted mount options string, overflow this buffer.
This causes KASAN to report a global-out-of-bounds write.

Fix it by truncating messages to the buffer size.

Link: http://lkml.kernel.org/r/20180707203621.30922-1-ebiggers3@gmail.com
Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: syzbot+b890b3335a4d8c608963@syzkaller.appspotmail.com
Signed-off-by: NEric Biggers <ebiggers@google.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Multiline statements with invalid %p<foo> uses produce multiple
warnings.  Fix that.

e.g.:

$ cat t_block.c
void foo(void)
{
	MY_DEBUG(drv->foo,
		 "%pk",
		 foo->boo);
}

$ ./scripts/checkpatch.pl -f t_block.c
WARNING: Missing or malformed SPDX-License-Identifier tag in line 1
#1: FILE: t_block.c:1:
+void foo(void)

WARNING: Invalid vsprintf pointer extension '%pk'
#3: FILE: t_block.c:3:
+	MY_DEBUG(drv->foo,
+		 "%pk",
+		 foo->boo);

WARNING: Invalid vsprintf pointer extension '%pk'
#3: FILE: t_block.c:3:
+	MY_DEBUG(drv->foo,
+		 "%pk",
+		 foo->boo);

total: 0 errors, 3 warnings, 6 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

t_block.c has style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.

Link: http://lkml.kernel.org/r/9e8341bbe4c9877d159cb512bb701043cbfbb10b.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Cc: "Tobin C. Harding" <me@tobin.cc>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

syzbot has noticed that a specially crafted library can easily hit
VM_BUG_ON in __mm_populate

  kernel BUG at mm/gup.c:1242!
  invalid opcode: 0000 [#1] SMP
  CPU: 2 PID: 9667 Comm: a.out Not tainted 4.18.0-rc3 #644
  Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
  RIP: 0010:__mm_populate+0x1e2/0x1f0
  Code: 55 d0 65 48 33 14 25 28 00 00 00 89 d8 75 21 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 75 18 f1 ff 0f 0b e8 6e 18 f1 ff <0f> 0b 31 db eb c9 e8 93 06 e0 ff 0f 1f 00 55 48 89 e5 53 48 89 fb
  Call Trace:
     vm_brk_flags+0xc3/0x100
     vm_brk+0x1f/0x30
     load_elf_library+0x281/0x2e0
     __ia32_sys_uselib+0x170/0x1e0
     do_fast_syscall_32+0xca/0x420
     entry_SYSENTER_compat+0x70/0x7f

The reason is that the length of the new brk is not page aligned when we
try to populate the it.  There is no reason to bug on that though.
do_brk_flags already aligns the length properly so the mapping is
expanded as it should.  All we need is to tell mm_populate about it.
Besides that there is absolutely no reason to to bug_on in the first
place.  The worst thing that could happen is that the last page wouldn't
get populated and that is far from putting system into an inconsistent
state.

Fix the issue by moving the length sanitization code from do_brk_flags
up to vm_brk_flags.  The only other caller of do_brk_flags is brk
syscall entry and it makes sure to provide the proper length so t here
is no need for sanitation and so we can use do_brk_flags without it.

Also remove the bogus BUG_ONs.

[osalvador@techadventures.net: fix up vm_brk_flags s@request@len@]
Link: http://lkml.kernel.org/r/20180706090217.GI32658@dhcp22.suse.czSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reported-by: Nsyzbot <syzbot+5dcb560fe12aa5091c06@syzkaller.appspotmail.com>
Tested-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: NOscar Salvador <osalvador@suse.de>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Huang, Ying" <ying.huang@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>

Mike Rapoport is converting architectures from bootmem to nobootmem
allocator.  While doing so for m68k Geert has noticed that he gets a
scary looking warning:

  WARNING: CPU: 0 PID: 0 at mm/memblock.c:230
  memblock_find_in_range_node+0x11c/0x1be
  memblock: bottom-up allocation failed, memory hotunplug may be affected
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted
  4.18.0-rc3-atari-01343-gf2fb5f2e09a97a3c-dirty #7
  Call Trace: __warn+0xa8/0xc2
    kernel_pg_dir+0x0/0x1000
    netdev_lower_get_next+0x2/0x22
    warn_slowpath_fmt+0x2e/0x36
    memblock_find_in_range_node+0x11c/0x1be
    memblock_find_in_range_node+0x11c/0x1be
    memblock_find_in_range_node+0x0/0x1be
    vprintk_func+0x66/0x6e
    memblock_virt_alloc_internal+0xd0/0x156
    netdev_lower_get_next+0x2/0x22
    netdev_lower_get_next+0x2/0x22
    kernel_pg_dir+0x0/0x1000
    memblock_virt_alloc_try_nid_nopanic+0x58/0x7a
    netdev_lower_get_next+0x2/0x22
    kernel_pg_dir+0x0/0x1000
    kernel_pg_dir+0x0/0x1000
    EXPTBL+0x234/0x400
    EXPTBL+0x234/0x400
    alloc_node_mem_map+0x4a/0x66
    netdev_lower_get_next+0x2/0x22
    free_area_init_node+0xe2/0x29e
    EXPTBL+0x234/0x400
    paging_init+0x430/0x462
    kernel_pg_dir+0x0/0x1000
    printk+0x0/0x1a
    EXPTBL+0x234/0x400
    setup_arch+0x1b8/0x22c
    start_kernel+0x4a/0x40a
    _sinittext+0x344/0x9e8

The warning is basically saying that a top-down allocation can break
memory hotremove because memblock allocation is not movable.  But m68k
doesn't even support MEMORY_HOTREMOVE so there is no point to warn about
it.

Make the warning conditional only to configurations that care.

Link: http://lkml.kernel.org/r/20180706061750.GH32658@dhcp22.suse.czSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Tested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Sam Creasey <sammy@sammy.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The current code does not make sure to page align bss before calling
vm_brk(), and this can lead to a VM_BUG_ON() in __mm_populate() due to
the requested lenght not being correctly aligned.

Let us make sure to align it properly.

Kees: only applicable to CONFIG_USELIB kernels: 32-bit and configured
for libc5.

Link: http://lkml.kernel.org/r/20180705145539.9627-1-osalvador@techadventures.netSigned-off-by: NOscar Salvador <osalvador@suse.de>
Reported-by: syzbot+5dcb560fe12aa5091c06@syzkaller.appspotmail.com
Tested-by: NTetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: NKees Cook <keescook@chromium.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- Build the kernel without the fix
- Add some flag to the purgatories KBUILD_CFLAGS,I used
  -fno-asynchronous-unwind-tables
- Re-build the kernel

When you look at makes output you see that sha256.o is not re-build in the
last step.  Also readelf -S still shows the .eh_frame section for
sha256.o.

With the fix sha256.o is rebuilt in the last step.

Without FORCE make does not detect changes only made to the command line
options.  So object files might not be re-built even when they should be.
Fix this by adding FORCE where it is missing.

Link: http://lkml.kernel.org/r/20180704110044.29279-2-prudo@linux.ibm.com
Fixes: df6f2801 ("kernel/kexec_file.c: move purgatories sha256 to common code")
Signed-off-by: NPhilipp Rudo <prudo@linux.ibm.com>
Acked-by: NDave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>	[4.17+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In my testing, the second mount will fail after umounting successfully.
The reason is that we put refcount of trans_mod in the correct case
rather than the error case in parse_opts() at last.  That will cause the
refcount decrease to -1, and when we try to get trans_mod again in
try_module_get(), we could only increase refcount to 0 which will cause
failure as follows:

parse_opts
  v9fs_get_trans_by_name
    try_module_get : return NULL to caller which cause error

So we should put refcount of trans_mod in error case.

Link: http://lkml.kernel.org/r/5B3F39A0.2030509@huawei.com
Fixes: 9421c3e6 ("net/9p/client.c: fix potential refcnt problem of trans module")
Signed-off-by: NJun Piao <piaojun@huawei.com>
Reviewed-by: NYiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
Reviewed-by: NDominique Martinet <dominique.martinet@cea.fr>
Tested-by: NDominique Martinet <dominique.martinet@cea.fr>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The mmu_gather APIs keep track of the invalidated address range
including the span covered by invalidated page table pages.  Ranges
covered by page tables but not ptes (and therefore no TLBs) still need
to be invalidated because some architectures (x86) can cache
intermediate page table entries, and invalidate those with normal TLB
invalidation instructions to be almost-backward-compatible.

Architectures which don't cache intermediate page table entries, or
which invalidate these caches separately from TLB invalidation, do not
require TLB invalidation range expanded over page tables.

Allow architectures to supply their own p??_free_tlb functions, which
can avoid the __tlb_adjust_range.

Link: http://lkml.kernel.org/r/20180703013131.2807-1-npiggin@gmail.comSigned-off-by: NNicholas Piggin <npiggin@gmail.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: "Aneesh Kumar K. V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The autofs subsystem does not check that the "path" parameter is present
for all cases where it is required when it is passed in via the "param"
struct.

In particular it isn't checked for the AUTOFS_DEV_IOCTL_OPENMOUNT_CMD
ioctl command.

To solve it, modify validate_dev_ioctl(function to check that a path has
been provided for ioctl commands that require it.

Link: http://lkml.kernel.org/r/153060031527.26631.18306637892746301555.stgit@pluto.themaw.netSigned-off-by: NTomas Bortoli <tomasbortoli@gmail.com>
Signed-off-by: NIan Kent <raven@themaw.net>
Reported-by: syzbot+60c837b428dc84e83a93@syzkaller.appspotmail.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Thomas reports:
 "While looking around in /proc on my v4.14.52 system I noticed that all
  processes got a lot of "Locked" memory in /proc/*/smaps. A lot more
  memory than a regular user can usually lock with mlock().

  Commit 493b0e9d (in v4.14-rc1) seems to have changed the behavior
  of "Locked".

  Before that commit the code was like this. Notice the VM_LOCKED check.

           (vma->vm_flags & VM_LOCKED) ?
                (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);

  After that commit Locked is now the same as Pss:

	  (unsigned long)(mss->pss >> (10 + PSS_SHIFT)));

  This looks like a mistake."

Indeed, the commit has added mss->pss_locked with the correct value that
depends on VM_LOCKED, but forgot to actually use it.  Fix it.

Link: http://lkml.kernel.org/r/ebf6c7fb-fec3-6a26-544f-710ed193c154@suse.cz
Fixes: 493b0e9d ("mm: add /proc/pid/smaps_rollup")
Signed-off-by: NVlastimil Babka <vbabka@suse.cz>
Reported-by: NThomas Lindroth <thomas.lindroth@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

KVM guests on s390 can notify the host of unused pages.  This can result
in pte_unused callbacks to be true for KVM guest memory.

If a page is unused (checked with pte_unused) we might drop this page
instead of paging it.  This can have side-effects on userfaultd, when
the page in question was already migrated:

The next access of that page will trigger a fault and a user fault
instead of faulting in a new and empty zero page.  As QEMU does not
expect a userfault on an already migrated page this migration will fail.

The most straightforward solution is to ignore the pte_unused hint if a
userfault context is active for this VMA.

Link: http://lkml.kernel.org/r/20180703171854.63981-1-borntraeger@de.ibm.comSigned-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We must zero struct pages for memory that is not backed by physical
memory, or kernel does not have access to.

Recently, there was a change which zeroed all memmap for all holes in
e820.  Unfortunately, it introduced a bug that is discussed here:

  https://www.spinics.net/lists/linux-mm/msg156764.html

Linus, also saw this bug on his machine, and confirmed that reverting
commit 124049de ("x86/e820: put !E820_TYPE_RAM regions into
memblock.reserved") fixes the issue.

The problem is that we incorrectly zero some struct pages after they
were setup.

The fix is to zero unavailable struct pages prior to initializing of
struct pages.

A more detailed fix should come later that would avoid double zeroing
cases: one in __init_single_page(), the other one in
zero_resv_unavail().

Fixes: 124049de ("x86/e820: put !E820_TYPE_RAM regions into memblock.reserved")
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull i2c fixes from Wolfram Sang:

 - I2C core bugfix regarding bus recovery

 - driver bugfix for the tegra driver

 - typo correction

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: recovery: if possible send STOP with recovery pulses
  i2c: tegra: Fix NACK error handling
  i2c: stu300: use non-archaic spelling of failes

Pull timer fixes from Ingo Molnar:
 "A clocksource driver fix and a revert"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: arm_arch_timer: Set arch_mem_timer cpumask to cpu_possible_mask
  Revert "tick: Prefer a lower rating device only if it's CPU local device"

Pull perf tool fixes from Ingo Molnar:
 "Misc tooling fixes: python3 related fixes, gcc8 fix, bashism fixes and
  some other smaller fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Use python-config --includes rather than --cflags
  perf script python: Fix dict reference counting
  perf stat: Fix --interval_clear option
  perf tools: Fix compilation errors on gcc8
  perf test shell: Prevent temporary editor files from being considered test scripts
  perf llvm-utils: Remove bashism from kernel include fetch script
  perf test shell: Make perf's inet_pton test more portable
  perf test shell: Replace '|&' with '2>&1 |' to work with more shells
  perf scripts python: Add Python 3 support to EventClass.py
  perf scripts python: Add Python 3 support to sched-migration.py
  perf scripts python: Add Python 3 support to Util.py
  perf scripts python: Add Python 3 support to SchedGui.py
  perf scripts python: Add Python 3 support to Core.py
  perf tools: Generate a Python script compatible with Python 2 and 3

Pull EFI fix from Ingo Molnar:
 "Fix a UEFI mixed mode (64-bit kernel on 32-bit UEFI) reboot loop
  regression"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/x86: Fix mixed mode reboot loop by removing pointless call to PciIo->Attributes()

Pull rseq fixes from Ingo Molnar:
 "Various rseq ABI fixes and cleanups: use get_user()/put_user(),
  validate parameters and use proper uapi types, etc"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq/selftests: cleanup: Update comment above rseq_prepare_unload
  rseq: Remove unused types_32_64.h uapi header
  rseq: uapi: Declare rseq_cs field as union, update includes
  rseq: uapi: Update uapi comments
  rseq: Use get_user/put_user rather than __get_user/__put_user
  rseq: Use __u64 for rseq_cs fields, validate user inputs

Pull rdma fixes from Jason Gunthorpe:
 "Things have been quite slow, only 6 RC patches have been sent to the
  list. Regression, user visible bugs, and crashing fixes:

   - cxgb4 could wrongly fail MR creation due to a typo

   - various crashes if the wrong QP type is mixed in with APIs that
     expect other types

   - syzkaller oops

   - using ERR_PTR and NULL together cases HFI1 to crash in some cases

   - mlx5 memory leak in error unwind"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/mlx5: Fix memory leak in mlx5_ib_create_srq() error path
  RDMA/uverbs: Don't fail in creation of multiple flows
  IB/hfi1: Fix incorrect mixing of ERR_PTR and NULL return values
  RDMA/uverbs: Fix slab-out-of-bounds in ib_uverbs_ex_create_flow
  RDMA/uverbs: Protect from attempts to create flows on unsupported QP
  iw_cxgb4: correctly enforce the max reg_mr depth

Pull VFIO fix from Alex Williamson:
 "Fix deadlock in mbochs sample driver (Alexey Khoroshilov)"

* tag 'vfio-v4.18-rc5' of git://github.com/awilliam/linux-vfio:
  sample: vfio-mdev: avoid deadlock in mdev_access()