nfs_init_sequence() will clear this for us.
Signed-off-by: Fred Isaman <fred.isaman@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the wait for a LOCK operation is interrupted, and then the file is
closed, the locks cleanup code will assume that no new locks will be added
to the inode after it has completed.  We already have a mechanism to detect
if there was signal, so let's use that to avoid recreating the local lock
once the RPC completes.  Also skip re-sending the LOCK operation for the
various error cases if we were signaled.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
[Trond: Fix inverted test of locks_lock_inode_wait()]
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If we get an ESTALE error in response to an RPC call operating on the
file on the MDS, we should immediately cancel the layout for that file.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

In nfs_idmap_read_and_verify_message there is an incorrect sprintf '%d'
that converts the __u32 'im_id' from struct idmap_msg to 'id_str', which
is a stack char array variable of length NFS_UINT_MAXLEN == 11.
If a uid or gid value is > 2147483647 = 0x7fffffff, the conversion
overflows into a negative value, for example:
crash> p (unsigned) (0x80000000)
$1 = 2147483648
crash> p (signed) (0x80000000)
$2 = -2147483648
The '-' sign is written to the buffer and this causes a 1 byte overflow
when the NULL byte is written, which corrupts kernel stack memory.  If
CONFIG_CC_STACKPROTECTOR_STRONG is set we see a stack-protector panic:

[11558053.616565] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffffa05b8a8c
[11558053.639063] CPU: 6 PID: 9423 Comm: rpc.idmapd Tainted: G        W      ------------ T 3.10.0-514.el7.x86_64 #1
[11558053.641990] Hardware name: Red Hat OpenStack Compute, BIOS 1.10.2-3.el7_4.1 04/01/2014
[11558053.644462]  ffffffff818c7bc0 00000000b1f3aec1 ffff880de0f9bd48 ffffffff81685eac
[11558053.646430]  ffff880de0f9bdc8 ffffffff8167f2b3 ffffffff00000010 ffff880de0f9bdd8
[11558053.648313]  ffff880de0f9bd78 00000000b1f3aec1 ffffffff811dcb03 ffffffffa05b8a8c
[11558053.650107] Call Trace:
[11558053.651347]  [<ffffffff81685eac>] dump_stack+0x19/0x1b
[11558053.653013]  [<ffffffff8167f2b3>] panic+0xe3/0x1f2
[11558053.666240]  [<ffffffff811dcb03>] ? kfree+0x103/0x140
[11558053.682589]  [<ffffffffa05b8a8c>] ? idmap_pipe_downcall+0x1cc/0x1e0 [nfsv4]
[11558053.689710]  [<ffffffff810855db>] __stack_chk_fail+0x1b/0x30
[11558053.691619]  [<ffffffffa05b8a8c>] idmap_pipe_downcall+0x1cc/0x1e0 [nfsv4]
[11558053.693867]  [<ffffffffa00209d6>] rpc_pipe_write+0x56/0x70 [sunrpc]
[11558053.695763]  [<ffffffff811fe12d>] vfs_write+0xbd/0x1e0
[11558053.702236]  [<ffffffff810acccc>] ? task_work_run+0xac/0xe0
[11558053.704215]  [<ffffffff811fec4f>] SyS_write+0x7f/0xe0
[11558053.709674]  [<ffffffff816964c9>] system_call_fastpath+0x16/0x1b

Fix this by calling the internally defined nfs_map_numeric_to_string()
function which properly uses '%u' to convert this __u32.  For consistency,
also replace the one other place where snprintf is called.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Reported-by: Stephen Johnston <sjohnsto@redhat.com>
Fixes: cf4ab538 ("NFSv4: Fix the string length returned by the idmapper")
Cc: stable@vger.kernel.org # v3.4+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We do not want to ignore ctime updates that originate from functions
such as link().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We may need to revalidate the change attribute, ctime and the nlinks count.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Ensure that a delegation doesn't cause us to skip initialising the inode
if it was incomplete when we exited nfs_fhget()
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Ensure that we register the fact that the inode ctime has changed.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Ensure that we pass down the inode of the file being deleted so
that we can return any delegation being held.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Even then it isn't really necessary. The reason why we may not want to
pass in a stateid in other cases is that we cannot use the delegation
credential.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Having these exist as two functions doesn't seem to add anything useful,
and I think merging them together makes this easier to follow.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We currently have a separate function just to set this, but I think it
makes more sense to set it at the same time as the other values in
nfs4_init_sequence()
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Rather than doing this in the generic NFS client code.  Let's put this
with the other v4 stuff so it's all in one place.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

This doesn't really need to be in the generic NFS client code, and I
think it makes more sense to keep the v4 code in one place.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

There are three places that walk all delegation for an nfs_client and
restart whenever they find something interesting - potentially
resulting in a quadratic search:  If there are 10,000 uninteresting
delegations followed by 10,000 interesting one, then the code
skips over 100,000,000 delegations, which can take a noticeable amount
of time.

Of these nfs_delegation_reap_unclaimed() and
nfs_reap_expired_delegations() are only called during unusual events:
a server reboots or reports expired delegations, probably due to a
network partition.  Optimizing these is not particularly important.

The third, nfs_client_return_marked_delegations(), is called
periodically via nfs_expire_unreferenced_delegations().  It could
cause periodic problems on a busy server.

New delegations are added to the end of the list, so if there are
10,000 open files with delegations, and 10,000 more recently opened files
that received delegations but are now closed, then
nfs_client_return_marked_delegations() can take seconds to skip over
the 10,000 open files 10,000 times.  That is a waste of time.

The avoid this waste a place-holder (an inode) is kept when locks are
dropped, so that the place can usually be found again after taking
rcu_readlock().  This place holder ensure that we find the right
starting point in the list of nfs_servers, and makes is probable that
we find the right starting point in the list of delegations.
We might need to occasionally restart at the head of that list.

It might be possible that the place_holder inode could lose its
delegation separately, and then get a new one using the same (freed
and then reallocated) 'struct nfs_delegation'.  Were this to happen,
the new delegation would be at the end of the list and we would miss
returning some other delegations.  This would have the effect of
unnecessarily delaying the return of some unused delegations until the
next time this function is called - typically 90 seconds later.  As
this is not a correctness issue and is vanishingly unlikely to happen,
it does not seem worth addressing.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

list_for_each_entry_from_rcu() is an RCU version of
list_for_each_entry_from().  It walks a linked list under rcu
protection, from a given start point.

It is similar to list_for_each_entry_continue_rcu() but starts *at*
the given position rather than *after* it.

Naturally, the start point must be known to be in the list.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

In three places we walk the list of delegations for an nfs_client
until an interesting one is found, then we act of that delegation
and restart the walk.

New delegations are added to the end of a list and the interesting
delegations are usually old, so in many case we won't repeat
a long walk over and over again, but it is possible - particularly if
the first server in the list has a large number of uninteresting
delegations.

In each cache the work done on interesting delegations will often
complete without sleeping, so this could loop many times without
giving up the CPU.

So add a cond_resched() at an appropriate point to avoid hogging the
CPU for too long.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

There are 3 places where we walk the list of delegations
for an nfs_client.
In each case there are two nested loops, one for nfs_servers
and one for nfs_delegations.

When we find an interesting delegation we try to get an active
reference to the server.  If that fails, it is pointless to
continue to look at the other delegation for the server as
we will never be able to get an active reference.
So instead of continuing in the inner loop, break out
and continue in the outer loop.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We can optimise away any lookup for a rename target, unless we're
being asked to revalidate a dentry that might be in use.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If nfs_lookup_revalidate() is called with LOOKUP_REVAL because a
previous path lookup failed, then we ought to force a full lookup
of the component name.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFSv4 should not need to perform an extra close-to-open GETATTR as part
of the process of looking up a regular file, since the OPEN call will
do that for us.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Merge tag 'nds32-for-linus-4.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux

Pull nds32 fixes from Greentime Hu:
 "Bug fixes and build error fixes for nds32"

* tag 'nds32-for-linus-4.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux:
  nds32: Fix compiler warning, Wstringop-overflow, in vdso.c
  nds32: Disable local irq before calling cpu_dcache_wb_page in copy_user_highpage
  nds32: Flush the cache of the page at vmaddr instead of kaddr in flush_anon_page
  nds32: Correct flush_dcache_page function
  nds32: Fix the unaligned access handler
  nds32: Renaming the file for unaligned access
  nds32: To fix a cache inconsistency issue by setting correct cacheability of NTC
  nds32: To refine readability of INT_MASK_INITAIAL_VAL
  nds32: Fix the virtual address may map too much range by tlbop issue.
  nds32: Fix the allmodconfig build. To make sure CONFIG_CPU_LITTLE_ENDIAN is default y
  nds32: Fix build failed because arch_trace_hardirqs_off is changed to trace_hardirqs_off.
  nds32: Fix the unknown type u8 issue.
  nds32: Fix the symbols undefined issue by exporting them.
  nds32: Fix xfs_buf built failed by export invalidate_kernel_vmap_range and flush_kernel_vmap_range
  nds32: Fix drivers/gpu/drm/udl/udl_fb.c building error by defining PAGE_SHARED
  nds32: Fix building error of crypto/xor.c by adding xor.h
  nds32: Fix building error when CONFIG_FREEZE is enabled.
  nds32: lib: To use generic lib instead of libgcc to prevent the symbol undefined issue.

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>