It's not used in the function so just remove it. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

This function already gets the page from which the two extent trees
are referenced. Simplify its signature by moving the code getting the
trees inside the function. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Change the behavior of rmdir(2) and allow it to delete an empty
subvolume by using btrfs_delete_subvolume() which is used by
btrfs_ioctl_snap_destroy().

This is a change in behaviour and has been requested by users. Deleting
the subvolume by ioctl requires root permissions while the rmdir way
does works with standard tools and syscalls for all users that can
access the subvolume.

The main usecase is to allow 'rm -rf /path/with/subvols' to simply work.
We were not able to find any nasty usability surprises, the intention is
to do the destructive rm. Without allowing rmdir, this would have to be
followed by the ioctl subvolume deletion, which is more of an annoyance.

Implementation details:

The required lock for @dir and inode of @dentry is already acquired in
vfs layer.

We need some check before deleting a subvolume. Permission check is done
in vfs layer, emptiness check is in btrfs_rmdir() and additional check
(i.e. neither the subvolume is a default subvolume nor send is in progress)
is in btrfs_delete_subvolume().

Note that in btrfs_ioctl_snap_destroy(), d_delete() is called after
btrfs_delete_subvolume(). For rmdir(2), d_delete() is called in vfs
layer later.
Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>

Factor out the second half of btrfs_ioctl_snap_destroy() as
btrfs_delete_subvolume(), which performs some subvolume specific checks
before deletion:

1. send is not in progress
2. the subvolume is not the default subvolume
3. the subvolume does not contain other subvolumes

and actual deletion process. btrfs_delete_subvolume() requires
inode_lock for both @dir and inode of @dentry. The remaining part of
btrfs_ioctl_snap_destroy() is mainly permission checks.

Note that call of d_delete() is not included in btrfs_delete_subvolume()
as this function will also be used by btrfs_rmdir() to delete an empty
subvolume and in that case d_delete() is called in VFS layer.

As a result, btrfs_unlink_subvol() and may_destroy_subvol()
become static functions. No functional changes.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>

This is a preparation work to refactor btrfs_ioctl_snap_destroy()
and to allow rmdir(2) to delete an empty subvolume.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor update of the function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>

With commit b18253ec57c0 ("btrfs: optimize free space tree bitmap
conversion"), there are no more callers to le_test_bit(). This patch
removes le_test_bit().
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Presently, convert_free_space_to_extents() does a linear scan of the
bitmap. We can speed this up with find_next_{bit,zero_bit}_le().

This patch replaces the linear scan with find_next_{bit,zero_bit}_le().
Testing shows a 20-33% decrease in execution time for
convert_free_space_to_extents().

Since we change bitmap to be unsigned long, we have to do some casting
for the bitmap cursor. In le_bitmap_set() it makes sense to use u8, as
we are doing bit operations. Everywhere else, we're just using it for
pointer arithmetic and not directly accessing it, so char seems more
appropriate.
Suggested-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

le_bitmap_set() is only used by free-space-tree, so move it there and
make it static. le_bitmap_clear() is not used, so remove it.
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

We really want to know to which filesystem the extent map events belong,
but as it cannot be reached from the extent_map pointers, we need to
pass it down the callchain.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Preparatory work to pass fs_info to btrfs_add_extent_mapping so we can
get a better tracepoint message. Extent maps do not need fs_info for
anything so we only add a dummy one without any other initialization.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Most of the strings are prefixed by the UUID of the filesystem that
generates the message, however there are a few events that still
opencode the macro magic and can be converted to the common macros.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

The preferred style is to avoid spaces between key and value and no
commas between key=values.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

The (unsigned long long) casts are not necessary since long ago.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

For consistency, use the %llu form.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

The size of ino_t depends on 32/64bit architecture type. Btrfs stores
the full 64bit inode anyway so we should use it.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

The second if is really a subcase of ret being less than 0. So
introduce a generic if (ret < 0) check, and inside have another if
which explicitly handles the -ENOSPC and any other errors. No
functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Locks should generally be released in the oppposite order they are
acquired. Generally lock acquisiton ordering is used to ensure
deadlocks don't happen. However, as becomes more complicated it's
best to also maintain proper unlock order so as to avoid possible dead
locks. This was found by code inspection and doesn't necessarily lead
to a deadlock scenario.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Currently __endio_write_update_ordered uses labels to implement
what is essentially a simple while loop. This makes the code more
cumbersome to follow than it actually has to be. No functional
changes. No xfstest regressions were found during testing.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Adds comments about BTRFS_FS_EXCL_OP to existing comments
about the device locks.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor updates ]
Signed-off-by: David Sterba <dsterba@suse.com>

It's used to print its pointer in a debug statement but doesn't really
bring any useful information to the error message.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

The function btrfs_get_block_group_info() was introduced by the
commit 5af3e8cc ("Btrfs: make filesystem read-only when submitting
 barrier fails") which used it in disk-io.c.

However, the function is only called in ioctl.c now.
Its parameter type btrfs_ioctl_space_info* is only for ioctl.

So, make it static and rename it to be original name
get_block_group_info.

No functional change.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

add_pinned_bytes really cares whether the bytes being pinned are either
data or metadata. To that effect it checks whether the 'owner' argument
is less than BTRFS_FIRST_FREE_OBJECTID (256). This works because
owner can really have 2 types of values:

 a) For metadata extents it holds the level at which the parent is in
    the btree. This amounts to owner having the values 0-7

 b) In case of modifying data extents, owner is the inode number
    to which those extents belongs.

Let's make this more explicit byt converting the owner parameter to a
boolean value and either pass it directly when we know the type of
extents we are working with (i.e. in btrfs_free_tree_block). In cases
when the parent function can be called on both metadata/data extents
perform the check in the caller. This hopefully makes the interface
of add_pinned_bytes more intuitive.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Merge tag 'kbuild-fixes-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild fixes from Masahiro Yamada:

 - enable '-fno-tree-loop-im' only when supported

 - add '-fno-PIE' option before the asm-goto test

* tag 'kbuild-fixes-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  Makefile: disable PIE before testing asm goto
  kbuild: gcov: enable -fno-tree-loop-im if supported

Pull ARM SoC fixes from Olof Johansson:
 "A few more fixes for v4.17:

   - a fix for a crash in scm_call_atomic on qcom platforms

   - display fix for Allwinner A10

   - a fix that re-enables ethernet on Allwinner H3 (C.H.I.P et al)

   - a fix for eMMC corruption on hikey

   - i2c-gpio descriptor tables for ixp4xx

  ... plus a small typo fix"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: Fix i2c-gpio GPIO descriptor tables
  arm64: dts: hikey: Fix eMMC corruption regression
  firmware: qcom: scm: Fix crash in qcom_scm_call_atomic1()
  ARM: sun8i: v3s: fix spelling mistake: "disbaled" -> "disabled"
  ARM: dts: sun4i: Fix incorrect clocks for displays
  ARM: dts: sun8i: h3: Re-enable EMAC on Orange Pi One

Pull x86 store buffer fixes from Thomas Gleixner:
 "Two fixes for the SSBD mitigation code:

   - expose SSBD properly to guests. This got broken when the CPU
     feature flags got reshuffled.

   - simplify the CPU detection logic to avoid duplicate entries in the
     tables"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/speculation: Simplify the CPU bug detection logic
  KVM/VMX: Expose SSBD properly to guests

Pull scheduler fixes from Thomas Gleixner:
 "Three fixes for scheduler and kthread code:

   - allow calling kthread_park() on an already parked thread

   - restore the sched_pi_setprio() tracepoint behaviour

   - clarify the unclear string for the scheduling domain debug output"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched, tracing: Fix trace_sched_pi_setprio() for deboosting
  kthread: Allow kthread_park() on a parked kthread
  sched/topology: Clarify root domain(s) debug string

ARM64: hisi fixes for 4.17

- Remove eMMC max-frequency property to fix eMMC corruption on hikey board

* tag 'hisi-fixes-for-4.17v2' of git://github.com/hisilicon/linux-hisi:
  arm64: dts: hikey: Fix eMMC corruption regression
Signed-off-by: Olof Johansson <olof@lixom.net>

I used bad names in my clumsiness when rewriting many board
files to use GPIO descriptors instead of platform data. A few
had the platform_device ID set to -1 which would indeed give
the device name "i2c-gpio".

But several had it set to >=0 which gives the names
"i2c-gpio.0", "i2c-gpio.1" ...

Fix the offending instances in the ARM tree. Sorry for the
mess.

Fixes: b2e63555 ("i2c: gpio: Convert to use descriptors")
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Simon Guinot <simon.guinot@sequanux.org>
Reported-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

Pull KVM fixes from Radim Krčmář:
 "PPC:

   - Close a hole which could possibly lead to the host timebase getting
     out of sync.

   - Three fixes relating to PTEs and TLB entries for radix guests.

   - Fix a bug which could lead to an interrupt never getting delivered
     to the guest, if it is pending for a guest vCPU when the vCPU gets
     offlined.

  s390:

   - Fix false negatives in VSIE validity check (Cc stable)

  x86:

   - Fix time drift of VMX preemption timer when a guest uses LAPIC
     timer in periodic mode (Cc stable)

   - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow
     migration from hosts that don't need retpoline mitigation (Cc
     stable)

   - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and
     CPUID.OSXSAVE (Cc stable)

   - Report correct RIP after Hyper-V hypercall #UD (introduced in
     -rc6)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: fix #UD address of failed Hyper-V hypercalls
  kvm: x86: IA32_ARCH_CAPABILITIES is always supported
  KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
  x86/kvm: fix LAPIC timer drift when guest uses periodic mode
  KVM: s390: vsie: fix < 8k check for the itdba
  KVM: PPC: Book 3S HV: Do ptesync in radix guest exit path
  KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority change
  KVM: PPC: Book3S HV: Make radix clear pte when unmapping
  KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in kvmppc_radix_tlbie_page
  KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry

This patch is a partial revert of
commit abd7d097 ("arm64: dts: hikey: Enable HS200 mode on eMMC")

which has been causing eMMC corruption on my HiKey board.

Symptoms usually looked like:

mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
...
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
mmc0: new HS200 MMC card at address 0001
...
dwmmc_k3 f723d000.dwmmc0: Unexpected command timeout, state 3
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
print_req_error: I/O error, dev mmcblk0, sector 8810504
Aborting journal on device mmcblk0p10-8.
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31)
mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0)
EXT4-fs error (device mmcblk0p10): ext4_journal_check_start:61: Detected aborted journal
EXT4-fs (mmcblk0p10): Remounting filesystem read-only

And quite often this would result in a disk that wouldn't properly
boot even with older kernels.

It seems the max-frequency property added by the above patch is
causing the problem, so remove it.

Cc: Ryan Grachek <ryan@edited.us>
Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: YongQin Liu <yongqin.liu@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Wei Xu <xuwei04@gmail.com>

Merge misc fixes from Andrew Morton:
 "16 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  kasan: fix memory hotplug during boot
  kasan: free allocated shadow memory on MEM_CANCEL_ONLINE
  checkpatch: fix macro argument precedence test
  init/main.c: include <linux/mem_encrypt.h>
  kernel/sys.c: fix potential Spectre v1 issue
  mm/memory_hotplug: fix leftover use of struct page during hotplug
  proc: fix smaps and meminfo alignment
  mm: do not warn on offline nodes unless the specific node is explicitly requested
  mm, memory_hotplug: make has_unmovable_pages more robust
  mm/kasan: don't vfree() nonexistent vm_area
  MAINTAINERS: change hugetlbfs maintainer and update files
  ipc/shm: fix shmat() nil address after round-down when remapping
  Revert "ipc/shm: Fix shmat mmap nil-page protection"
  idr: fix invalid ptr dereference on item delete
  ocfs2: revert "ocfs2/o2hb: check len for bio_add_page() to avoid getting incorrect bio"
  mm: fix nr_rotate_swap leak in swapon() error case

Pull networking fixes from David Miller:
 "Let's begin the holiday weekend with some networking fixes:

   1) Whoops need to restrict cfg80211 wiphy names even more to 64
      bytes. From Eric Biggers.

   2) Fix flags being ignored when using kernel_connect() with SCTP,
      from Xin Long.

   3) Use after free in DCCP, from Alexey Kodanev.

   4) Need to check rhltable_init() return value in ipmr code, from Eric
      Dumazet.

   5) XDP handling fixes in virtio_net from Jason Wang.

   6) Missing RTA_TABLE in rtm_ipv4_policy[], from Roopa Prabhu.

   7) Need to use IRQ disabling spinlocks in mlx4_qp_lookup(), from Jack
      Morgenstein.

   8) Prevent out-of-bounds speculation using indexes in BPF, from
      Daniel Borkmann.

   9) Fix regression added by AF_PACKET link layer cure, from Willem de
      Bruijn.

  10) Correct ENIC dma mask, from Govindarajulu Varadarajan.

  11) Missing config options for PMTU tests, from Stefano Brivio"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (48 commits)
  ibmvnic: Fix partial success login retries
  selftests/net: Add missing config options for PMTU tests
  mlx4_core: allocate ICM memory in page size chunks
  enic: set DMA mask to 47 bit
  ppp: remove the PPPIOCDETACH ioctl
  ipv4: remove warning in ip_recv_error
  net : sched: cls_api: deal with egdev path only if needed
  vhost: synchronize IOTLB message with dev cleanup
  packet: fix reserve calculation
  net/mlx5: IPSec, Fix a race between concurrent sandbox QP commands
  net/mlx5e: When RXFCS is set, add FCS data into checksum calculation
  bpf: properly enforce index mask to prevent out-of-bounds speculation
  net/mlx4: Fix irq-unsafe spinlock usage
  net: phy: broadcom: Fix bcm_write_exp()
  net: phy: broadcom: Fix auxiliary control register reads
  net: ipv4: add missing RTA_TABLE to rtm_ipv4_policy
  net/mlx4: fix spelling mistake: "Inrerface" -> "Interface" and rephrase message
  ibmvnic: Only do H_EOI for mobility events
  tuntap: correctly set SOCKWQ_ASYNC_NOSPACE
  virtio-net: fix leaking page for gso packet during mergeable XDP
  ...

Using module_init() is wrong.  E.g.  ACPI adds and onlines memory before
our memory notifier gets registered.

This makes sure that ACPI memory detected during boot up will not result
in a kernel crash.

Easily reproducible with QEMU, just specify a DIMM when starting up.

Link: http://lkml.kernel.org/r/20180522100756.18478-3-david@redhat.com
Fixes: 786a8959 ("kasan: disable memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We have to free memory again when we cancel onlining, otherwise a later
onlining attempt will fail.

Link: http://lkml.kernel.org/r/20180522100756.18478-2-david@redhat.com
Fixes: fa69b598 ("mm/kasan: add support for memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch's macro argument precedence test is broken so fix it.

Link: http://lkml.kernel.org/r/5dd900e9197febc1995604bb33c23c136d8b33ce.camel@perches.comSigned-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In commit c7753208 ("x86, swiotlb: Add memory encryption support") a
call to function `mem_encrypt_init' was added.  Include prototype
defined in header <linux/mem_encrypt.h> to prevent a warning reported
during compilation with W=1:

  init/main.c:494:20: warning: no previous prototype for `mem_encrypt_init' [-Wmissing-prototypes]

Link: http://lkml.kernel.org/r/20180522195533.31415-1-malat@debian.orgSigned-off-by: Mathieu Malaterre <malat@debian.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Gargi Sharma <gs051095@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

`resource' can be controlled by user-space, hence leading to a potential
exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

  kernel/sys.c:1474 __do_compat_sys_old_getrlimit() warn: potential spectre issue 'get_current()->signal->rlim' (local cap)
  kernel/sys.c:1455 __do_sys_old_getrlimit() warn: potential spectre issue 'get_current()->signal->rlim' (local cap)

Fix this by sanitizing *resource* before using it to index
current->signal->rlim

Notice that given that speculation windows are large, the policy is to
kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Link: http://lkml.kernel.org/r/20180515030038.GA11822@embeddedor.comSigned-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The case of a new numa node got missed in avoiding using the node info
from page_struct during hotplug.  In this path we have a call to
register_mem_sect_under_node (which allows us to specify it is hotplug
so don't change the node), via link_mem_sections which unfortunately
does not.

Fix is to pass check_nid through link_mem_sections as well and disable
it in the new numa node path.

Note the bug only 'sometimes' manifests depending on what happens to be
in the struct page structures - there are lots of them and it only needs
to match one of them.

The result of the bug is that (with a new memory only node) we never
successfully call register_mem_sect_under_node so don't get the memory
associated with the node in sysfs and meminfo for the node doesn't
report it.

It came up whilst testing some arm64 hotplug patches, but appears to be
universal.  Whilst I'm triggering it by removing then reinserting memory
to a node with no other elements (thus making the node disappear then
appear again), it appears it would happen on hotplugging memory where
there was none before and it doesn't seem to be related the arm64
patches.

These patches call __add_pages (where most of the issue was fixed by
Pavel's patch).  If there is a node at the time of the __add_pages call
then all is well as it calls register_mem_sect_under_node from there
with check_nid set to false.  Without a node that function returns
having not done the sysfs related stuff as there is no node to use.
This is expected but it is the resulting path that fails...

Exact path to the problem is as follows:

 mm/memory_hotplug.c: add_memory_resource()

   The node is not online so we enter the 'if (new_node)' twice, on the
   second such block there is a call to link_mem_sections which calls
   into

  drivers/node.c: link_mem_sections() which calls

  drivers/node.c: register_mem_sect_under_node() which calls
     get_nid_for_pfn and keeps trying until the output of that matches
     the expected node (passed all the way down from
     add_memory_resource)

It is effectively the same fix as the one referred to in the fixes tag
just in the code path for a new node where the comments point out we
have to rerun the link creation because it will have failed in
register_new_memory (as there was no node at the time).  (actually that
comment is wrong now as we don't have register_new_memory any more it
got renamed to hotplug_memory_register in Pavel's patch).

Link: http://lkml.kernel.org/r/20180504085311.1240-1-Jonathan.Cameron@huawei.com
Fixes: fc44f7f9 ("mm/memory_hotplug: don't read nid from struct page during hotplug")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.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>

The 4.17-rc /proc/meminfo and /proc/<pid>/smaps look ugly: single-digit
numbers (commonly 0) are misaligned.

Remove seq_put_decimal_ull_width()'s leftover optimization for single
digits: it's wrong now that num_to_str() takes care of the width.

Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1805241554210.1326@eggly.anvils
Fixes: d1be35cb ("proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps")
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>