Current memset implementation in abiv1 is wrong and it'll cause unalign
access. Just remove it and use the generic one. This patch will cause
performance degradation and we will improve it with a new design in next
patchset.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

There are two generations of tlb operation instruction for C-SKY.
First generation is use mcr register and it need software do more
things, second generation is use specific instructions, eg:
 tlbi.va, tlbi.vas, tlbi.alls

We implemented the following functions:

 - flush_tlb_range (a range of entries)
 - flush_tlb_page (one entry)

 Above functions use asid from vma->mm to invalid tlb entries and
 we could use tlbi.vas instruction for newest generation csky cpu.

 - flush_tlb_kernel_range
 - flush_tlb_one

 Above functions don't care asid and it invalid the tlb entries only
 with vpn and we could use tlbi.vaas instruction for newest generat-
 ion csky cpu.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

Use linux generic asid/vmid algorithm to implement csky
switch_mm function. The algorithm is from arm and it could
work with SMP system. It'll help reduce tlb flush for
switch_mm in task/vm switch.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

This patch only contains asid help code from arm for next patch to
use.

The asid allocator use five level check to reduce the cost of
switch_mm.

 1. Check if the asid version is the same (it's general)
 2. Check reserved_asid which is set in rollover flush_context()
    and key point is to keep the same bit position with the current
    asid version instead of input version.
 3. Check if the position of bitmap is free then it could be set &
    used directly.
 4. find_next_zero_bit() (a little performance cost)
 5. flush_context  (this is the worst cost with increase current asid
    version)

Check is level by level and cost is also higher with the next level.
The reserved_asid and bitmap mechanism prevent unnecessary
find_next_zero_bit().

The atomic 64 bit asid is also suitable for 32-bit system and it
won't cost a lot in 1th 2th 3th level check.

The operation of set/clear mm_cpumask was removed in arm64 compared to
arm32. It seems no side effect on current arm64 system, but from
software meaning it's wrong. Although csky also needn't it, we add it
back for csky.

The asid_per_ctxt is no use for csky and it reserves the lowest bits for
other use, maybe: trust zone ? Ok, just keep it in csky copy.

Seems it also could be used by other archs and it's worth to move asid
code to generic in future.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Julien Grall <julien.grall@arm.com>

Current C-SKY ASID mechanism is from mips and it doesn't work well
with multi-cores. ASID per core mechanism is not suitable for C-SKY
SMP tlb maintain operations, eg: tlbi.vas need share the same asid
in all processors and it'll invalid the tlb entry in all cores with
the same asid.

This patch is prepare for new ASID mechanism.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

This patch adds the documentation to describe that how to add pmu node in
dts.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>

Add trigger type setting for csky,mpintc. The driver also could
support #interrupt-cells <1> and it wouldn't invalidate existing
DTs. Here we only show the complete format.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Rob Herring <robh+dt@kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>

CK810 pmu only support event with index 0-8 and 0xd; CK860 only
support event 1~4, 0xa~0x1b. So do not register unsupport event
to hardware cache event, which may leader to unknown behavior.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>

csky_pmu_event_init is called several times during the perf record
initialzation. After configure the event counter in either kernel
space or user space, csky_pmu_event_init is called twice with no
attr specified. Configuration will be overwritten with sampling in
both kernel space and user space. --all-kernel/--all-user is
useless without this patch applied.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

This patch add interrupt request and handler for csky pmu.
perf can record on hardware event with this patch applied.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

The csky pmu counter may have different io width. When the counter is
smaller then 64 bits and counter value is smaller than the old value, it
will result to a extremely large delta value. So the sampled value should
be extend to 64 bits to avoid this, the extension bits base on the
count-width property from dts.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

This patch change the csky pmu initialization from arch init to
device init. The pmu can be configued with information from
device tree(pmu device name, irq number and etc.).

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>

These traps couldn't be hanppen in kernel and we must panic there not
send a signal to userspace.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

Let arch help to select interrupt controller's and timer's drivers
instead of people using menuconfig to select. This help the mini system
boot up.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

Pull powerpc fix from Michael Ellerman:
 "One fix for a regression in my commit adding KUAP (Kernel User Access
  Prevention) on Radix, which incorrectly touched the AMR in the early
  machine check handler.

  Thanks to Nicholas Piggin"

* tag 'powerpc-5.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s/exception: Fix machine check early corrupting AMR

Pull SMP fixes from Thomas Gleixner:
 "Two small changes for the cpu hotplug code:

   - Prevent out of bounds access which actually might crash the machine
     caused by a missing bounds check in the fail injection code

   - Warn about unsupported migitation mode command line arguments to
     make people aware that they typoed the paramater. Not necessarily a
     fix but quite some people tripped over that"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Fix out-of-bounds read when setting fail state
  cpu/speculation: Warn on unsupported mitigations= parameter

Pull x86 fixes from Ingo Molnar:
 "Misc fixes all over the place:

   - might_sleep() atomicity fix in the microcode loader

   - resctrl boundary condition fix

   - APIC arithmethics bug fix for frequencies >= 4.2 GHz

   - three 5-level paging crash fixes

   - two speculation fixes

   - a perf/stacktrace fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/unwind/orc: Fall back to using frame pointers for generated code
  perf/x86: Always store regs->ip in perf_callchain_kernel()
  x86/speculation: Allow guests to use SSBD even if host does not
  x86/mm: Handle physical-virtual alignment mismatch in phys_p4d_init()
  x86/boot/64: Add missing fixup_pointer() for next_early_pgt access
  x86/boot/64: Fix crash if kernel image crosses page table boundary
  x86/apic: Fix integer overflow on 10 bit left shift of cpu_khz
  x86/resctrl: Prevent possible overrun during bitmap operations
  x86/microcode: Fix the microcode load on CPU hotplug for real

Pull perf fixes from Ingo Molnar:
 "Various fixes, most of them related to bugs perf fuzzing found in the
  x86 code"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/regs: Use PERF_REG_EXTENDED_MASK
  perf/x86: Remove pmu->pebs_no_xmm_regs
  perf/x86: Clean up PEBS_XMM_REGS
  perf/x86/regs: Check reserved bits
  perf/x86: Disable extended registers for non-supported PMUs
  perf/ioctl: Add check for the sample_period value
  perf/core: Fix perf_sample_regs_user() mm check

Pull irq fixes from Ingo Molnar:
 "Diverse irqchip driver fixes"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Fix command queue pointer comparison bug
  irqchip/mips-gic: Use the correct local interrupt map registers
  irqchip/ti-sci-inta: Fix kernel crash if irq_create_fwspec_mapping fail
  irqchip/irq-csky-mpintc: Support auto irq deliver to all cpus

Pull EFI fixes from Ingo Molnar:
 "Four fixes:
   - fix a kexec crash on arm64
   - fix a reboot crash on some Android platforms
   - future-proof the code for upcoming ACPI 6.2 changes
   - fix a build warning on x86"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efibc: Replace variable set function in notifier call
  x86/efi: fix a -Wtype-limits compilation warning
  efi/bgrt: Drop BGRT status field reserved bits check
  efi/memreserve: deal with memreserve entries in unmapped memory

Pull power management fix from Rafael Wysocki:
 "Avoid skipping bus-level PCI power management during system resume for
  PCIe ports left in D0 during the preceding suspend transition on
  platforms where the power states of those ports can change out of the
  PCI layer's control"

* tag 'pm-5.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PCI: PM: Avoid skipping bus-level PM on platforms without ACPI

Pull XArray fixes from Matthew Wilcox:

 - Account XArray nodes for the page cache to the appropriate cgroup
   (Johannes Weiner)

 - Fix idr_get_next() when called under the RCU lock (Matthew Wilcox)

 - Add a test for xa_insert() (Matthew Wilcox)

* tag 'xarray-5.2-rc6' of git://git.infradead.org/users/willy/linux-dax:
  XArray tests: Add check_insert
  idr: Fix idr_get_next race with idr_remove
  mm: fix page cache convergence regression

Merge misc fixes from Andrew Morton:
 "15 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  linux/kernel.h: fix overflow for DIV_ROUND_UP_ULL
  mm, swap: fix THP swap out
  fork,memcg: alloc_thread_stack_node needs to set tsk->stack
  MAINTAINERS: add CLANG/LLVM BUILD SUPPORT info
  mm/vmalloc.c: avoid bogus -Wmaybe-uninitialized warning
  mm/page_idle.c: fix oops because end_pfn is larger than max_pfn
  initramfs: fix populate_initrd_image() section mismatch
  mm/oom_kill.c: fix uninitialized oc->constraint
  mm: hugetlb: soft-offline: dissolve_free_huge_page() return zero on !PageHuge
  mm: soft-offline: return -EBUSY if set_hwpoison_free_buddy_page() fails
  signal: remove the wrong signal_pending() check in restore_user_sigmask()
  fs/binfmt_flat.c: make load_flat_shared_library() work
  mm/mempolicy.c: fix an incorrect rebind node in mpol_rebind_nodemask
  fs/proc/array.c: allow reporting eip/esp for all coredumping threads
  mm/dev_pfn: exclude MEMORY_DEVICE_PRIVATE while computing virtual address

Pull ARC fixes from Vineet Gupta:

 - hsdk platform unifying apertures

 - build system CROSS_COMPILE prefix

* tag 'arc-5.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: [plat-hsdk]: unify memory apertures configuration
  ARC: build: Try to guess CROSS_COMPILE with cc-cross-prefix

Pull RISC-V fixes from Paul Walmsley:
 "Minor RISC-V fixes and one defconfig update.

  The fixes have no functional impact:

   - Fix some comment text in the memory management vmalloc_fault path.

   - Fix some warnings from the DT compiler in our newly-added DT files.

   - Change the newly-added DT bindings such that SoC IP blocks with
     external I/O are marked as "disabled" by default, then enable them
     explicitly in board DT files when the devices are used on the
     board. This aligns the bindings with existing upstream practice.

   - Add the MIT license as an option for a minor header file, at the
     request of one of the U-Boot maintainers.

  The RISC-V defconfig update builds the SiFive SPI driver and the
  MMC-SPI driver by default. The intention here is to make v5.2 more
  usable for testers and users with RISC-V hardware"

* tag 'riscv-for-v5.2/fixes-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: mm: Fix code comment
  dt-bindings: clock: sifive: add MIT license as an option for the header file
  dt-bindings: riscv: resolve 'make dt_binding_check' warnings
  riscv: dts: Re-organize the DT nodes
  RISC-V: defconfig: enable MMC & SPI for RISC-V

Pull two more NFS client fixes from Anna Schumaker:
 "These are both stable fixes.

  One to calculate the correct client message length in the case of
  partial transmissions. And the other to set the proper TCP timeout for
  flexfiles"

* tag 'nfs-for-5.2-4' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS/flexfiles: Use the correct TCP timeout for flexfiles I/O
  SUNRPC: Fix up calculation of client message length

Pull ceph fix from Ilya Dryomov:
 "A small fix for a potential -rc1 regression from Jeff"

* tag 'ceph-for-5.2-rc7' of git://github.com/ceph/ceph-client:
  ceph: fix ceph_mdsc_build_path to not stop on first component

Pull SCSI fix from James Bottomley:
 "One simple fix for a driver use after free"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: vmw_pscsi: Fix use-after-free in pvscsi_queue_lck()

Pull block fixes from Jens Axboe:
 "Just two small fixes.

  One from Paolo, fixing a silly mistake in BFQ. The other one is from
  me, ensuring that we have ->file cleared in the io_uring request a bit
  earlier. That avoids a use-before-free, if we encounter an error
  before ->file is assigned"

* tag 'for-linus-20190628' of git://git.kernel.dk/linux-block:
  block, bfq: fix operator in BFQQ_TOTALLY_SEEKY
  io_uring: ensure req->file is cleared on allocation

Pull pin control fixes from Linus Walleij:
 "Sorry to bomb in fixes this late. Maybe I can comfort you by saying it
  is only driver fixes, and mostly IRQ handling which is something GPIO
  and pin control drivers never get right. You think it works and then
  it doesn't.

  Summary:

   - Fix IRQ setup in the MCP23s08.

   - Fix pin setup on pins > 31 in the Ocelot driver.

   - Fix IRQs in the Mediatek driver"

* tag 'pinctrl-v5.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: mediatek: Update cur_mask in mask/mask ops
  pinctrl: mediatek: Ignore interrupts that are wake only during resume
  pinctrl: ocelot: fix pinmuxing for pins after 31
  pinctrl: ocelot: fix gpio direction for pins after 31
  pinctrl: mcp23s08: Fix add_data and irqchip_add_nested call order

DIV_ROUND_UP_ULL adds the two arguments and then invokes
DIV_ROUND_DOWN_ULL.  But on a 32bit system the addition of two 32 bit
values can overflow.  DIV_ROUND_DOWN_ULL does it correctly and stashes
the addition into a unsigned long long so cast the result to unsigned
long long here to avoid the overflow condition.

[akpm@linux-foundation.org: DIV_ROUND_UP_ULL must be an rval]
Link: http://lkml.kernel.org/r/20190625100518.30753-1-vkoul@kernel.org


Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

0-Day test system reported some OOM regressions for several THP
(Transparent Huge Page) swap test cases.  These regressions are bisected
to 68614289 ("block: always define BIO_MAX_PAGES as 256").  In the
commit, BIO_MAX_PAGES is set to 256 even when THP swap is enabled.  So the
bio_alloc(gfp_flags, 512) in get_swap_bio() may fail when swapping out
THP.  That causes the OOM.

As in the patch description of 68614289 ("block: always define
BIO_MAX_PAGES as 256"), THP swap should use multi-page bvec to write THP
to swap space.  So the issue is fixed via doing that in get_swap_bio().

BTW: I remember I have checked the THP swap code when 68614289
("block: always define BIO_MAX_PAGES as 256") was merged, and thought the
THP swap code needn't to be changed.  But apparently, I was wrong.  I
should have done this at that time.

Link: http://lkml.kernel.org/r/20190624075515.31040-1-ying.huang@intel.com
Fixes: 68614289

 ("block: always define BIO_MAX_PAGES as 256")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 5eed6f1d ("fork,memcg: fix crash in free_thread_stack on
memcg charge fail") corrected two instances, but there was a third
instance of this bug.

Without setting tsk->stack, if memcg_charge_kernel_stack fails, it'll
execute free_thread_stack() on a dangling pointer.

Enterprise kernels are compiled with VMAP_STACK=y so this isn't
critical, but custom VMAP_STACK=n builds should have some performance
advantage, with the drawback of risking to fail fork because compaction
didn't succeed.  So as long as VMAP_STACK=n is a supported option it's
worth fixing it upstream.

Link: http://lkml.kernel.org/r/20190619011450.28048-1-aarcange@redhat.com
Fixes: 9b6f7e16

 ("mm: rework memcg kernel stack accounting")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add keyword support so that our mailing list gets cc'ed for clang/llvm
patches.  We're pretty active on our mailing list so far as code review.
There are numerous Googlers like myself that are paid to support
building the Linux kernel with Clang and LLVM.

Link: http://lkml.kernel.org/r/20190620001907.255803-1-ndesaulniers@google.com


Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gcc gets confused in pcpu_get_vm_areas() because there are too many
branches that affect whether 'lva' was initialized before it gets used:

  mm/vmalloc.c: In function 'pcpu_get_vm_areas':
  mm/vmalloc.c:991:4: error: 'lva' may be used uninitialized in this function [-Werror=maybe-uninitialized]
      insert_vmap_area_augment(lva, &va->rb_node,
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
       &free_vmap_area_root, &free_vmap_area_list);
       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  mm/vmalloc.c:916:20: note: 'lva' was declared here
    struct vmap_area *lva;
                      ^~~

Add an intialization to NULL, and check whether this has changed before
the first use.

[akpm@linux-foundation.org: tweak comments]
Link: http://lkml.kernel.org/r/20190618092650.2943749-1-arnd@arndb.de
Fixes: 68ad4a33

 ("mm/vmalloc.c: keep track of free blocks for vmap allocation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Joel Fernandes <joelaf@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently the calcuation of end_pfn can round up the pfn number to more
than the actual maximum number of pfns, causing an Oops.  Fix this by
ensuring end_pfn is never more than max_pfn.

This can be easily triggered when on systems where the end_pfn gets
rounded up to more than max_pfn using the idle-page stress-ng stress test:

sudo stress-ng --idle-page 0

  BUG: unable to handle kernel paging request at 00000000000020d8
  #PF error: [normal kernel read fault]
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  CPU: 1 PID: 11039 Comm: stress-ng-idle- Not tainted 5.0.0-5-generic #6-Ubuntu
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
  RIP: 0010:page_idle_get_page+0xc8/0x1a0
  Code: 0f b1 0a 75 7d 48 8b 03 48 89 c2 48 c1 e8 33 83 e0 07 48 c1 ea 36 48 8d 0c 40 4c 8d 24 88 49 c1 e4 07 4c 03 24 d5 00 89 c3 be <49> 8b 44 24 58 48 8d b8 80 a1 02 00 e8 07 d5 77 00 48 8b 53 08 48
  RSP: 0018:ffffafd7c672fde8 EFLAGS: 00010202
  RAX: 0000000000000005 RBX: ffffe36341fff700 RCX: 000000000000000f
  RDX: 0000000000000284 RSI: 0000000000000275 RDI: 0000000001fff700
  RBP: ffffafd7c672fe00 R08: ffffa0bc34056410 R09: 0000000000000276
  R10: ffffa0bc754e9b40 R11: ffffa0bc330f6400 R12: 0000000000002080
  R13: ffffe36341fff700 R14: 0000000000080000 R15: ffffa0bc330f6400
  FS: 00007f0ec1ea5740(0000) GS:ffffa0bc7db00000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000000020d8 CR3: 0000000077d68000 CR4: 00000000000006e0
  Call Trace:
    page_idle_bitmap_write+0x8c/0x140
    sysfs_kf_bin_write+0x5c/0x70
    kernfs_fop_write+0x12e/0x1b0
    __vfs_write+0x1b/0x40
    vfs_write+0xab/0x1b0
    ksys_write+0x55/0xc0
    __x64_sys_write+0x1a/0x20
    do_syscall_64+0x5a/0x110
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

Link: http://lkml.kernel.org/r/20190618124352.28307-1-colin.king@canonical.com
Fixes: 33c3fc71

 ("mm: introduce idle page tracking")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With gcc-4.6.3:

    WARNING: vmlinux.o(.text.unlikely+0x140): Section mismatch in reference from the function populate_initrd_image() to the variable .init.ramfs.info:__initramfs_size
    The function populate_initrd_image() references
    the variable __init __initramfs_size.
    This is often because populate_initrd_image lacks a __init
    annotation or the annotation of __initramfs_size is wrong.

    WARNING: vmlinux.o(.text.unlikely+0x14c): Section mismatch in reference from the function populate_initrd_image() to the function .init.text:unpack_to_rootfs()
    The function populate_initrd_image() references
    the function __init unpack_to_rootfs().
    This is often because populate_initrd_image lacks a __init
    annotation or the annotation of unpack_to_rootfs is wrong.

    WARNING: vmlinux.o(.text.unlikely+0x198): Section mismatch in reference from the function populate_initrd_image() to the function .init.text:xwrite()
    The function populate_initrd_image() references
    the function __init xwrite().
    This is often because populate_initrd_image lacks a __init
    annotation or the annotation of xwrite is wrong.

Indeed, if the compiler decides not to inline populate_initrd_image(), a
warning is generated.

Fix this by adding the missing __init annotations.

Link: http://lkml.kernel.org/r/20190617074340.12779-1-geert@linux-m68k.org
Fixes: 7c184ecd

 ("initramfs: factor out a helper to populate the initrd image")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In dump_oom_summary() oc->constraint is used to show oom_constraint_text,
but it hasn't been set before.  So the value of it is always the default
value 0.  We should inititialize it before.

Bellow is the output when memcg oom occurs,

before this patch:
  oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null), cpuset=/,mems_allowed=0,oom_memcg=/foo,task_memcg=/foo,task=bash,pid=7997,uid=0

after this patch:
  oom-kill:constraint=CONSTRAINT_MEMCG,nodemask=(null), cpuset=/,mems_allowed=0,oom_memcg=/foo,task_memcg=/foo,task=bash,pid=13681,uid=0

Link: http://lkml.kernel.org/r/1560522038-15879-1-git-send-email-laoar.shao@gmail.com
Fixes: ef8444ea

 ("mm, oom: reorganize the oom report in dump_header")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Wind Yu <yuzhoujian@didichuxing.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

madvise(MADV_SOFT_OFFLINE) often returns -EBUSY when calling soft offline
for hugepages with overcommitting enabled.  That was caused by the
suboptimal code in current soft-offline code.  See the following part:

    ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
                            MIGRATE_SYNC, MR_MEMORY_FAILURE);
    if (ret) {
            ...
    } else {
            /*
             * We set PG_hwpoison only when the migration source hugepage
             * was successfully dissolved, because otherwise hwpoisoned
             * hugepage remains on free hugepage list, then userspace will
             * find it as SIGBUS by allocation failure. That's not expected
             * in soft-offlining.
             */
            ret = dissolve_free_huge_page(page);
            if (!ret) {
                    if (set_hwpoison_free_buddy_page(page))
                            num_poisoned_pages_inc();
            }
    }
    return ret;

Here dissolve_free_huge_page() returns -EBUSY if the migration source page
was freed into buddy in migrate_pages(), but even in that case we actually
has a chance that set_hwpoison_free_buddy_page() succeeds.  So that means
current code gives up offlining too early now.

dissolve_free_huge_page() checks that a given hugepage is suitable for
dissolving, where we should return success for !PageHuge() case because
the given hugepage is considered as already dissolved.

This change also affects other callers of dissolve_free_huge_page(), which
are cleaned up together.

[n-horiguchi@ah.jp.nec.com: v3]
  Link: http://lkml.kernel.org/r/1560761476-4651-3-git-send-email-n-horiguchi@ah.jp.nec.comLink: http://lkml.kernel.org/r/1560154686-18497-3-git-send-email-n-horiguchi@ah.jp.nec.com
Fixes: 6bc9b564

 ("mm: fix race on soft-offlining")
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Chen, Jerry T <jerry.t.chen@intel.com>
Tested-by: Chen, Jerry T <jerry.t.chen@intel.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Xishi Qiu <xishi.qiuxishi@alibaba-inc.com>
Cc: "Chen, Jerry T" <jerry.t.chen@intel.com>
Cc: "Zhuo, Qiuxu" <qiuxu.zhuo@intel.com>
Cc: <stable@vger.kernel.org>	[4.19+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>