Variable 'cache' is being assigned but is never used hence it is
redundant and can be removed.

Cleans up clang warning:
warning: variable 'cache' set but not used [-Wunused-but-set-variable]
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

get_seconds() returns an unsigned long can overflow on some architectures
and is deprecated because of that. In cachefs, we cast that number to
a a 32-bit integer, which will overflow in year 2106 on all architectures.

As confirmed by David Howells, the overflow probably isn't harmful
in the end, since the timestamps are only used to make the file names
unique, but they don't strictly have to be in monotonically increasing
order since the files only exist in order to be deleted as quickly
as possible.

Moving to ktime_get_real_seconds() avoids the deprecated interface.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Clang warns when one enumerated type is implicitly converted to another.

fs/cachefiles/namei.c:247:50: warning: implicit conversion from
enumeration type 'enum cachefiles_obj_ref_trace' to different
enumeration type 'enum fscache_obj_ref_trace' [-Wenum-conversion]
        cache->cache.ops->put_object(&xobject->fscache,
cachefiles_obj_put_wait_retry);

Silence this warning by explicitly casting to fscache_obj_ref_trace,
which is also done in put_object.
Reported-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NNathan Chancellor <natechancellor@gmail.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

It was observed that a process blocked indefintely in
__fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP
to be cleared via fscache_wait_for_deferred_lookup().

At this time, ->backing_objects was empty, which would normaly prevent
__fscache_read_or_alloc_page() from getting to the point of waiting.
This implies that ->backing_objects was cleared *after*
__fscache_read_or_alloc_page was was entered.

When an object is "killed" and then "dropped",
FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then
KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is
->backing_objects cleared.  This leaves a window where
something else can set FSCACHE_COOKIE_LOOKING_UP and
__fscache_read_or_alloc_page() can start waiting, before
->backing_objects is cleared

There is some uncertainty in this analysis, but it seems to be fit the
observations.  Adding the wake in this patch will be handled correctly
by __fscache_read_or_alloc_page(), as it checks if ->backing_objects
is empty again, after waiting.

Customer which reported the hang, also report that the hang cannot be
reproduced with this fix.

The backtrace for the blocked process looked like:

PID: 29360  TASK: ffff881ff2ac0f80  CPU: 3   COMMAND: "zsh"
 #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1
 #1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed
 #2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8
 #3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e
 #4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache]
 #5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache]
 #6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs]
 #7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs]
 #8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73
 #9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs]
#10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756
#11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa
#12 [ffff881ff43eff18] sys_read at ffffffff811fda62
#13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e
Signed-off-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

[Description]

In a heavily loaded system where the system pagecache is nearing memory
limits and fscache is enabled, pages can be leaked by fscache while trying
read pages from cachefiles backend.  This can happen because two
applications can be reading same page from a single mount, two threads can
be trying to read the backing page at same time.  This results in one of
the threads finding that a page for the backing file or netfs file is
already in the radix tree.  During the error handling cachefiles does not
clean up the reference on backing page, leading to page leak.

[Fix]
The fix is straightforward, to decrement the reference when error is
encountered.

  [dhowells: Note that I've removed the clearance and put of newpage as
   they aren't attested in the commit message and don't appear to actually
   achieve anything since a new page is only allocated is newpage!=NULL and
   any residual new page is cleared before returning.]

[Testing]
I have tested the fix using following method for 12+ hrs.

1) mkdir -p /mnt/nfs ; mount -o vers=3,fsc <server_ip>:/export /mnt/nfs
2) create 10000 files of 2.8MB in a NFS mount.
3) start a thread to simulate heavy VM presssure
   (while true ; do echo 3 > /proc/sys/vm/drop_caches ; sleep 1 ; done)&
4) start multiple parallel reader for data set at same time
   find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
   find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
   find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
   ..
   ..
   find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
   find /mnt/nfs -type f | xargs -P 80 cat > /dev/null &
5) finally check using cat /proc/fs/fscache/stats | grep -i pages ;
   free -h , cat /proc/meminfo and page-types -r -b lru
   to ensure all pages are freed.
Reviewed-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NShantanu Goel <sgoel01@yahoo.com>
Signed-off-by: NKiran Kumar Modukuri <kiran.modukuri@gmail.com>
[dja: forward ported to current upstream]
Signed-off-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

The code in fscache_retrieval_complete is using atomic_sub followed by an
atomic_read:

        atomic_sub(n_pages, &op->n_pages);
        if (atomic_read(&op->n_pages) <= 0)
                fscache_op_complete(&op->op, true);

This causes two threads doing a decrement of n_pages to race with each
other seeing the op->refcount 0 at same time - and they end up calling
fscache_op_complete() in both the threads leading to an assertion failure.

Fix this by using atomic_sub_return_relaxed() instead of two calls.  Note
that I'm using 'relaxed' rather than, say, 'release' as there aren't
multiple variables that appear to need ordering across the release.

The oops looks something like:

FS-Cache: Assertion failed
FS-Cache: 0 > 0 is false
...
kernel BUG at /usr/src/linux-4.4.0/fs/fscache/operation.c:449!
...
Workqueue: fscache_operation fscache_op_work_func [fscache]
...
RIP: 0010:[<ffffffffc037eacd>] fscache_op_complete+0x10d/0x180 [fscache]
...
Call Trace:
 [<ffffffffc1464cf9>] cachefiles_read_copier+0x3a9/0x410 [cachefiles]
 [<ffffffffc037e272>] fscache_op_work_func+0x22/0x50 [fscache]
 [<ffffffff81096da0>] process_one_work+0x150/0x3f0
 [<ffffffff8109751a>] worker_thread+0x11a/0x470
 [<ffffffff81808e59>] ? __schedule+0x359/0x980
 [<ffffffff81097400>] ? rescuer_thread+0x310/0x310
 [<ffffffff8109cdd6>] kthread+0xd6/0xf0
 [<ffffffff8109cd00>] ? kthread_park+0x60/0x60
 [<ffffffff8180d0cf>] ret_from_fork+0x3f/0x70
 [<ffffffff8109cd00>] ? kthread_park+0x60/0x60

This seen this in 4.4.x kernels and the same bug affects fscache in latest
upstreams kernels.

Fixes: 1bb4b7f9 ("FS-Cache: The retrieval remaining-pages counter needs to be atomic_t")
Signed-off-by: NKiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

If cachefiles gets an error other then ENOENT when trying to look up an
object in the cache (in this case, EACCES), the object state machine will
eventually transition to the DROP_OBJECT state.

This state invokes fscache_drop_object() which tries to sync the auxiliary
data with the cache (this is done lazily since commit 402cb8dd) on an
incomplete cache object struct.

The problem comes when cachefiles_update_object_xattr() is called to
rewrite the xattr holding the data.  There's an assertion there that the
cache object points to a dentry as we're going to update its xattr.  The
assertion trips, however, as dentry didn't get set.

Fix the problem by skipping the update in cachefiles if the object doesn't
refer to a dentry.  A better way to do it could be to skip the update from
the DROP_OBJECT state handler in fscache, but that might deny the cache the
opportunity to update intermediate state.

If this error occurs, the kernel log includes lines that look like the
following:

 CacheFiles: Lookup failed error -13
 CacheFiles:
 CacheFiles: Assertion failed
 ------------[ cut here ]------------
 kernel BUG at fs/cachefiles/xattr.c:138!
 ...
 Workqueue: fscache_object fscache_object_work_func [fscache]
 RIP: 0010:cachefiles_update_object_xattr.cold.4+0x18/0x1a [cachefiles]
 ...
 Call Trace:
  cachefiles_update_object+0xdd/0x1c0 [cachefiles]
  fscache_update_aux_data+0x23/0x30 [fscache]
  fscache_drop_object+0x18e/0x1c0 [fscache]
  fscache_object_work_func+0x74/0x2b0 [fscache]
  process_one_work+0x18d/0x340
  worker_thread+0x2e/0x390
  ? pwq_unbound_release_workfn+0xd0/0xd0
  kthread+0x112/0x130
  ? kthread_bind+0x30/0x30
  ret_from_fork+0x35/0x40

Note that there are actually two issues here: (1) EACCES happened on a
cache object and (2) an oops occurred.  I think that the second is a
consequence of the first (it certainly looks like it ought to be).  This
patch only deals with the second.

Fixes: 402cb8dd ("fscache: Attach the index key and aux data to the cookie")
Reported-by: NZhibin Li <zhibli@redhat.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Pull dma-mapping fixes from Christoph Hellwig:
 "Two dma-direct / swiotlb regressions fixes:

   - zero is a valid physical address on some arm boards, we can't use
     it as the error value

   - don't try to cache flush the error return value (no matter what it
     is)"

* tag 'dma-mapping-4.20-3' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: Skip cache maintenance on map error
  dma-direct: Make DIRECT_MAPPING_ERROR viable for SWIOTLB

Pull NFS client bugfixes from Trond Myklebust:

 - Fix a NFSv4 state manager deadlock when returning a delegation

 - NFSv4.2 copy do not allocate memory under the lock

 - flexfiles: Use the correct stateid for IO in the tightly coupled case

* tag 'nfs-for-4.20-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  flexfiles: use per-mirror specified stateid for IO
  NFSv4.2 copy do not allocate memory under the lock
  NFSv4: Fix a NFSv4 state manager deadlock

I'm taking over the maintainance of Sparse so add myself as
maintainer and move Christopher's info to CREDITS.
Signed-off-by: NLuc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull XArray updates from Matthew Wilcox:
 "We found some bugs in the DAX conversion to XArray (and one bug which
  predated the XArray conversion). There were a couple of bugs in some
  of the higher-level functions, which aren't actually being called in
  today's kernel, but surfaced as a result of converting existing radix
  tree & IDR users over to the XArray.

  Some of the other changes to how the higher-level APIs work were also
  motivated by converting various users; again, they're not in use in
  today's kernel, so changing them has a low probability of introducing
  a bug.

  Dan can still trigger a bug in the DAX code with hot-offline/online,
  and we're working on tracking that down"

* tag 'xarray-4.20-rc4' of git://git.infradead.org/users/willy/linux-dax:
  XArray tests: Add missing locking
  dax: Avoid losing wakeup in dax_lock_mapping_entry
  dax: Fix huge page faults
  dax: Fix dax_unlock_mapping_entry for PMD pages
  dax: Reinstate RCU protection of inode
  dax: Make sure the unlocking entry isn't locked
  dax: Remove optimisation from dax_lock_mapping_entry
  XArray tests: Correct some 64-bit assumptions
  XArray: Correct xa_store_range
  XArray: Fix Documentation
  XArray: Handle NULL pointers differently for allocation
  XArray: Unify xa_store and __xa_store
  XArray: Add xa_store_bh() and xa_store_irq()
  XArray: Turn xa_erase into an exported function
  XArray: Unify xa_cmpxchg and __xa_cmpxchg
  XArray: Regularise xa_reserve
  nilfs2: Use xa_erase_irq
  XArray: Export __xa_foo to non-GPL modules
  XArray: Fix xa_for_each with a single element at 0

Pull HID fixes from Jiri Kosina:

 - revert of the high-resolution scrolling feature, as it breaks certain
   hardware due to incompatibilities between Logitech and Microsoft
   worlds. Peter Hutterer is working on a fixed implementation. Until
   that is finished, revert by Benjamin Tissoires.

 - revert of incorrect strncpy->strlcpy conversion in uhid, from David
   Herrmann

 - fix for buggy sendfile() implementation on uhid device node, from
   Eric Biggers

 - a few assorted device-ID specific quirks

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
  Revert "Input: Add the `REL_WHEEL_HI_RES` event code"
  Revert "HID: input: Create a utility class for counting scroll events"
  Revert "HID: logitech: Add function to enable HID++ 1.0 "scrolling acceleration""
  Revert "HID: logitech: Enable high-resolution scrolling on Logitech mice"
  Revert "HID: logitech: Use LDJ_DEVICE macro for existing Logitech mice"
  Revert "HID: logitech: fix a used uninitialized GCC warning"
  Revert "HID: input: simplify/fix high-res scroll event handling"
  HID: Add quirk for Primax PIXART OEM mice
  HID: i2c-hid: Disable runtime PM for LG touchscreen
  HID: multitouch: Add pointstick support for Cirque Touchpad
  HID: steam: remove input device when a hid client is running.
  Revert "HID: uhid: use strlcpy() instead of strncpy()"
  HID: uhid: forbid UHID_CREATE under KERNEL_DS or elevated privileges
  HID: input: Ignore battery reported by Symbol DS4308
  HID: Add quirk for Microsoft PIXART OEM mouse

Pull arm64 fixes from Catalin Marinas::

 - Fix wrong conflict resolution around CONFIG_ARM64_SSBD

 - Fix sparse warning on unsigned long constant

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: cpufeature: Fix mismerge of CONFIG_ARM64_SSBD block
  arm64: sysreg: fix sparse warnings

Pull networking fixes from David Miller:

 1) Need to take mutex in ath9k_add_interface(), from Dan Carpenter.

 2) Fix mt76 build without CONFIG_LEDS_CLASS, from Arnd Bergmann.

 3) Fix socket wmem accounting in SCTP, from Xin Long.

 4) Fix failed resume crash in ena driver, from Arthur Kiyanovski.

 5) qed driver passes bytes instead of bits into second arg of
    bitmap_weight(). From Denis Bolotin.

 6) Fix reset deadlock in ibmvnic, from Juliet Kim.

 7) skb_scrube_packet() needs to scrub the fwd marks too, from Petr
    Machata.

 8) Make sure older TCP stacks see enough dup ACKs, and avoid doing SACK
    compression during this period, from Eric Dumazet.

 9) Add atomicity to SMC protocol cursor handling, from Ursula Braun.

10) Don't leave dangling error pointer if bpf_prog_add() fails in
    thunderx driver, from Lorenzo Bianconi. Also, when we unmap TSO
    headers, set sq->tso_hdrs to NULL.

11) Fix race condition over state variables in act_police, from Davide
    Caratti.

12) Disable guest csum in the presence of XDP in virtio_net, from Jason
    Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (64 commits)
  net: gemini: Fix copy/paste error
  net: phy: mscc: fix deadlock in vsc85xx_default_config
  dt-bindings: dsa: Fix typo in "probed"
  net: thunderx: set tso_hdrs pointer to NULL in nicvf_free_snd_queue
  net: amd: add missing of_node_put()
  team: no need to do team_notify_peers or team_mcast_rejoin when disabling port
  virtio-net: fail XDP set if guest csum is negotiated
  virtio-net: disable guest csum during XDP set
  net/sched: act_police: add missing spinlock initialization
  net: don't keep lonely packets forever in the gro hash
  net/ipv6: re-do dad when interface has IFF_NOARP flag change
  packet: copy user buffers before orphan or clone
  ibmvnic: Update driver queues after change in ring size support
  ibmvnic: Fix RX queue buffer cleanup
  net: thunderx: set xdp_prog to NULL if bpf_prog_add fails
  net/dim: Update DIM start sample after each DIM iteration
  net: faraday: ftmac100: remove netif_running(netdev) check before disabling interrupts
  net/smc: use after free fix in smc_wr_tx_put_slot()
  net/smc: atomic SMCD cursor handling
  net/smc: add SMC-D shutdown signal
  ...

Pull xfs fixes from Darrick Wong:
 "Dave and I have continued our work fixing corruption problems that can
  be found when running long-term burn-in exercisers on xfs. Here are
  some patches fixing most of the problems, but there will likely be
  more. :/

   - Numerous corruption fixes for copy on write

   - Numerous corruption fixes for blocksize < pagesize writes

   - Don't miscalculate AG reservations for small final AGs

   - Fix page cache truncation to work properly for reflink and extent
     shifting

   - Fix use-after-free when retrying failed inode/dquot buffer logging

   - Fix corruptions seen when using copy_file_range in directio mode"

* tag 'xfs-4.20-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: readpages doesn't zero page tail beyond EOF
  vfs: vfs_dedupe_file_range() doesn't return EOPNOTSUPP
  iomap: dio data corruption and spurious errors when pipes fill
  iomap: sub-block dio needs to zeroout beyond EOF
  iomap: FUA is wrong for DIO O_DSYNC writes into unwritten extents
  xfs: delalloc -> unwritten COW fork allocation can go wrong
  xfs: flush removing page cache in xfs_reflink_remap_prep
  xfs: extent shifting doesn't fully invalidate page cache
  xfs: finobt AG reserves don't consider last AG can be a runt
  xfs: fix transient reference count error in xfs_buf_resubmit_failed_buffers
  xfs: uncached buffer tracing needs to print bno
  xfs: make xfs_file_remap_range() static
  xfs: fix shared extent data corruption due to missing cow reservation

The TX stats should be started with the tx_stats_syncp,
there seems to be a copy/paste error in the driver.
Signed-off-by: NAndreas Fiedler <andreas.fiedler@gmx.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The vsc85xx_default_config function called in the vsc85xx_config_init
function which is used by VSC8530, VSC8531, VSC8540 and VSC8541 PHYs
mistakenly calls phy_read and phy_write in-between phy_select_page and
phy_restore_page.

phy_select_page and phy_restore_page actually take and release the MDIO
bus lock and phy_write and phy_read take and release the lock to write
or read to a PHY register.

Let's fix this deadlock by using phy_modify_paged which handles
correctly a read followed by a write in a non-standard page.

Fixes: 6a0bfbbe ("net: phy: mscc: migrate to phy_select/restore_page functions")
Signed-off-by: NQuentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The correct form is "can be probed", so fix the typo.
Signed-off-by: NFabio Estevam <festevam@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reset snd_queue tso_hdrs pointer to NULL in nicvf_free_snd_queue routine
since it is used to check if tso dma descriptor queue has been previously
allocated. The issue can be triggered with the following reproducer:

$ip link set dev enP2p1s0v0 xdpdrv obj xdp_dummy.o
$ip link set dev enP2p1s0v0 xdpdrv off

[  341.467649] WARNING: CPU: 74 PID: 2158 at mm/vmalloc.c:1511 __vunmap+0x98/0xe0
[  341.515010] Hardware name: GIGABYTE H270-T70/MT70-HD0, BIOS T49 02/02/2018
[  341.521874] pstate: 60400005 (nZCv daif +PAN -UAO)
[  341.526654] pc : __vunmap+0x98/0xe0
[  341.530132] lr : __vunmap+0x98/0xe0
[  341.533609] sp : ffff00001c5db860
[  341.536913] x29: ffff00001c5db860 x28: 0000000000020000
[  341.542214] x27: ffff810feb5090b0 x26: ffff000017e57000
[  341.547515] x25: 0000000000000000 x24: 00000000fbd00000
[  341.552816] x23: 0000000000000000 x22: ffff810feb5090b0
[  341.558117] x21: 0000000000000000 x20: 0000000000000000
[  341.563418] x19: ffff000017e57000 x18: 0000000000000000
[  341.568719] x17: 0000000000000000 x16: 0000000000000000
[  341.574020] x15: 0000000000000010 x14: ffffffffffffffff
[  341.579321] x13: ffff00008985eb27 x12: ffff00000985eb2f
[  341.584622] x11: ffff0000096b3000 x10: ffff00001c5db510
[  341.589923] x9 : 00000000ffffffd0 x8 : ffff0000086868e8
[  341.595224] x7 : 3430303030303030 x6 : 00000000000006ef
[  341.600525] x5 : 00000000003fffff x4 : 0000000000000000
[  341.605825] x3 : 0000000000000000 x2 : ffffffffffffffff
[  341.611126] x1 : ffff0000096b3728 x0 : 0000000000000038
[  341.616428] Call trace:
[  341.618866]  __vunmap+0x98/0xe0
[  341.621997]  vunmap+0x3c/0x50
[  341.624961]  arch_dma_free+0x68/0xa0
[  341.628534]  dma_direct_free+0x50/0x80
[  341.632285]  nicvf_free_resources+0x160/0x2d8 [nicvf]
[  341.637327]  nicvf_config_data_transfer+0x174/0x5e8 [nicvf]
[  341.642890]  nicvf_stop+0x298/0x340 [nicvf]
[  341.647066]  __dev_close_many+0x9c/0x108
[  341.650977]  dev_close_many+0xa4/0x158
[  341.654720]  rollback_registered_many+0x140/0x530
[  341.659414]  rollback_registered+0x54/0x80
[  341.663499]  unregister_netdevice_queue+0x9c/0xe8
[  341.668192]  unregister_netdev+0x28/0x38
[  341.672106]  nicvf_remove+0xa4/0xa8 [nicvf]
[  341.676280]  nicvf_shutdown+0x20/0x30 [nicvf]
[  341.680630]  pci_device_shutdown+0x44/0x88
[  341.684720]  device_shutdown+0x144/0x250
[  341.688640]  kernel_restart_prepare+0x44/0x50
[  341.692986]  kernel_restart+0x20/0x68
[  341.696638]  __se_sys_reboot+0x210/0x238
[  341.700550]  __arm64_sys_reboot+0x24/0x30
[  341.704555]  el0_svc_handler+0x94/0x110
[  341.708382]  el0_svc+0x8/0xc
[  341.711252] ---[ end trace 3f4019c8439959c9 ]---
[  341.715874] page:ffff7e0003ef4000 count:0 mapcount:0 mapping:0000000000000000 index:0x4
[  341.723872] flags: 0x1fffe000000000()
[  341.727527] raw: 001fffe000000000 ffff7e0003f1a008 ffff7e0003ef4048 0000000000000000
[  341.735263] raw: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
[  341.742994] page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)

where xdp_dummy.c is a simple bpf program that forwards the incoming
frames to the network stack (available here:
https://github.com/altoor/xdp_walkthrough_examples/blob/master/sample_1/xdp_dummy.c)

Fixes: 05c773f5 ("net: thunderx: Add basic XDP support")
Fixes: 4863dea3 ("net: Adding support for Cavium ThunderX network controller")
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

of_find_node_by_path() acquires a reference to the node
returned by it and that reference needs to be dropped by its caller.
This place doesn't do that, so fix it.
Signed-off-by: NYangtao Li <tiny.windzz@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

team_notify_peers() will send ARP and NA to notify peers. team_mcast_rejoin()
will send multicast join group message to notify peers. We should do this when
enabling/changed to a new port. But it doesn't make sense to do it when a port
is disabled.

On the other hand, when we set mcast_rejoin_count to 2, and do a failover,
team_port_disable() will increase mcast_rejoin.count_pending to 2 and then
team_port_enable() will increase mcast_rejoin.count_pending to 4. We will send
4 mcast rejoin messages at latest, which will make user confused. The same
with notify_peers.count.

Fix it by deleting team_notify_peers() and team_mcast_rejoin() in
team_port_disable().
Reported-by: NLiang Li <liali@redhat.com>
Fixes: fc423ff0 ("team: add peer notification")
Fixes: 492b200e ("team: add support for sending multicast rejoins")
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We don't support partial csumed packet since its metadata will be lost
or incorrect during XDP processing. So fail the XDP set if guest_csum
feature is negotiated.

Fixes: f600b690 ("virtio_net: Add XDP support")
Reported-by: NJesper Dangaard Brouer <brouer@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Pavel Popa <pashinho1990@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We don't disable VIRTIO_NET_F_GUEST_CSUM if XDP was set. This means we
can receive partial csumed packets with metadata kept in the
vnet_hdr. This may have several side effects:

- It could be overridden by header adjustment, thus is might be not
  correct after XDP processing.
- There's no way to pass such metadata information through
  XDP_REDIRECT to another driver.
- XDP does not support checksum offload right now.

So simply disable guest csum if possible in this the case of XDP.

Fixes: 3f93522f ("virtio-net: switch off offloads on demand if possible on XDP set")
Reported-by: NJesper Dangaard Brouer <brouer@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Pavel Popa <pashinho1990@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pullk ceph fix from Ilya Dryomov:
 "A messenger fix, marked for stable"

* tag 'ceph-for-4.20-rc4' of https://github.com/ceph/ceph-client:
  libceph: fall back to sendmsg for slab pages

Pull block fix from Jens Axboe:
 "Just a single fix for this week, fixing an issue with nvme-fc"

* tag 'for-linus-20181123' of git://git.kernel.dk/linux-block:
  nvme-fc: resolve io failures during connect

commit f2cbd485 ("net/sched: act_police: fix race condition on state
variables") introduces a new spinlock, but forgets its initialization.
Ensure that tcf_police_init() initializes 'tcfp_lock' every time a 'police'
action is newly created, to avoid the following lockdep splat:

 INFO: trying to register non-static key.
 the code is fine but needs lockdep annotation.
 turning off the locking correctness validator.
 <...>
 Call Trace:
  dump_stack+0x85/0xcb
  register_lock_class+0x581/0x590
  __lock_acquire+0xd4/0x1330
  ? tcf_police_init+0x2fa/0x650 [act_police]
  ? lock_acquire+0x9e/0x1a0
  lock_acquire+0x9e/0x1a0
  ? tcf_police_init+0x2fa/0x650 [act_police]
  ? tcf_police_init+0x55a/0x650 [act_police]
  _raw_spin_lock_bh+0x34/0x40
  ? tcf_police_init+0x2fa/0x650 [act_police]
  tcf_police_init+0x2fa/0x650 [act_police]
  tcf_action_init_1+0x384/0x4c0
  tcf_action_init+0xf6/0x160
  tcf_action_add+0x73/0x170
  tc_ctl_action+0x122/0x160
  rtnetlink_rcv_msg+0x2a4/0x490
  ? netlink_deliver_tap+0x99/0x400
  ? validate_linkmsg+0x370/0x370
  netlink_rcv_skb+0x4d/0x130
  netlink_unicast+0x196/0x230
  netlink_sendmsg+0x2e5/0x3e0
  sock_sendmsg+0x36/0x40
  ___sys_sendmsg+0x280/0x2f0
  ? _raw_spin_unlock+0x24/0x30
  ? handle_pte_fault+0xafe/0xf30
  ? find_held_lock+0x2d/0x90
  ? syscall_trace_enter+0x1df/0x360
  ? __sys_sendmsg+0x5e/0xa0
  __sys_sendmsg+0x5e/0xa0
  do_syscall_64+0x60/0x210
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 RIP: 0033:0x7f1841c7cf10
 Code: c3 48 8b 05 82 6f 2c 00 f7 db 64 89 18 48 83 cb ff eb dd 0f 1f 80 00 00 00 00 83 3d 8d d0 2c 00 00 75 10 b8 2e 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae cc 00 00 48 89 04 24
 RSP: 002b:00007ffcf9df4d68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f1841c7cf10
 RDX: 0000000000000000 RSI: 00007ffcf9df4dc0 RDI: 0000000000000003
 RBP: 000000005bf56105 R08: 0000000000000002 R09: 00007ffcf9df8edc
 R10: 00007ffcf9df47e0 R11: 0000000000000246 R12: 0000000000671be0
 R13: 00007ffcf9df4e84 R14: 0000000000000008 R15: 0000000000000000

Fixes: f2cbd485 ("net/sched: act_police: fix race condition on state variables")
Reported-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric noted that with UDP GRO and NAPI timeout, we could keep a single
UDP packet inside the GRO hash forever, if the related NAPI instance
calls napi_gro_complete() at an higher frequency than the NAPI timeout.
Willem noted that even TCP packets could be trapped there, till the
next retransmission.
This patch tries to address the issue, flushing the old packets -
those with a NAPI_GRO_CB age before the current jiffy - before scheduling
the NAPI timeout. The rationale is that such a timeout should be
well below a jiffy and we are not flushing packets eligible for sane GRO.

v1  -> v2:
 - clarified the commit message and comment

RFC -> v1:
 - added 'Fixes tags', cleaned-up the wording.
Reported-by: NEric Dumazet <eric.dumazet@gmail.com>
Fixes: 3b47d303 ("net: gro: add a per device gro flush timer")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we add a new IPv6 address, we should also join corresponding solicited-node
multicast address, unless the interface has IFF_NOARP flag, as function
addrconf_join_solict() did. But if we remove IFF_NOARP flag later, we do
not do dad and add the mcast address. So we will drop corresponding neighbour
discovery message that came from other nodes.

A typical example is after creating a ipvlan with mode l3, setting up an ipv6
address and changing the mode to l2. Then we will not be able to ping this
address as the interface doesn't join related solicited-node mcast address.

Fix it by re-doing dad when interface changed IFF_NOARP flag. Then we will add
corresponding mcast group and check if there is a duplicate address on the
network.
Reported-by: NJianlin Shi <jishi@redhat.com>
Reviewed-by: NStefano Brivio <sbrivio@redhat.com>
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull IOMMU fixes from Joerg Roedel:

 - Two fixes for the Intel VT-d driver to fix a NULL-ptr dereference and
   an unbalance in an allocate/free path (allocated with memremap, freed
   with iounmap)

 - Fix for a crash in the Renesas IOMMU driver

 - Fix for the Advanced Virtual Interrupt Controler (AVIC) code in the
   AMD IOMMU driver

* tag 'iommu-fixes-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Use memunmap to free memremap
  amd/iommu: Fix Guest Virtual APIC Log Tail Address Register
  iommu/ipmmu-vmsa: Fix crash on early domain free
  iommu/vt-d: Fix NULL pointer dereference in prq_event_thread()

tpacket_snd sends packets with user pages linked into skb frags. It
notifies that pages can be reused when the skb is released by setting
skb->destructor to tpacket_destruct_skb.

This can cause data corruption if the skb is orphaned (e.g., on
transmit through veth) or cloned (e.g., on mirror to another psock).

Create a kernel-private copy of data in these cases, same as tun/tap
zerocopy transmission. Reuse that infrastructure: mark the skb as
SKBTX_ZEROCOPY_FRAG, which will trigger copy in skb_orphan_frags(_rx).

Unlike other zerocopy packets, do not set shinfo destructor_arg to
struct ubuf_info. tpacket_destruct_skb already uses that ptr to notify
when the original skb is released and a timestamp is recorded. Do not
change this timestamp behavior. The ubuf_info->callback is not needed
anyway, as no zerocopy notification is expected.

Mark destructor_arg as not-a-uarg by setting the lower bit to 1. The
resulting value is not a valid ubuf_info pointer, nor a valid
tpacket_snd frame address. Add skb_zcopy_.._nouarg helpers for this.

The fix relies on features introduced in commit 52267790 ("sock:
add MSG_ZEROCOPY"), so can be backported as is only to 4.14.

Tested with from `./in_netns.sh ./txring_overwrite` from
http://github.com/wdebruij/kerneltools/tests

Fixes: 69e3c75f ("net: TX_RING and packet mmap")
Reported-by: NAnand H. Krishnan <anandhkrishnan@gmail.com>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull ACPI fix from Rafael Wysocki:
 "Prevent the ACPI core from registering a platform device for the
  SMB0001 HID to avoid IRQ allocation issues (Hans de Goede)"

* tag 'acpi-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / platform: Add SMB0001 HID to forbidden_id_list

Pull power management fixes from Rafael Wysocki:
 "These fix two issues in the Operating Performance Points (OPP)
  framework, one cpufreq driver issue, one problem related to the tasks
  freezer and a few build-related issues in the cpupower utility.

  Specifics:

   - Fix tasks freezer deadlock in de_thread() that occurs if one of its
     sub-threads has been frozen already (Chanho Min).

   - Avoid registering a platform device by the ti-cpufreq driver on
     platforms that cannot use it (Dave Gerlach).

   - Fix a mistake in the ti-opp-supply operating performance points
     (OPP) driver that caused an incorrect reference voltage to be used
     and make it adjust the minimum voltage dynamically to avoid hangs
     or crashes in some cases (Keerthy).

   - Fix issues related to compiler flags in the cpupower utility and
     correct a linking problem in it by renaming a file with a duplicate
     name (Jiri Olsa, Konstantin Khlebnikov)"

* tag 'pm-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  exec: make de_thread() freezable
  cpufreq: ti-cpufreq: Only register platform_device when supported
  opp: ti-opp-supply: Correct the supply in _get_optimal_vdd_voltage call
  opp: ti-opp-supply: Dynamically update u_volt_min
  tools cpupower: Override CFLAGS assignments
  tools cpupower debug: Allow to use outside build flags
  tools/power/cpupower: fix compilation with STATIC=true

When merging support for SSBD and the CRC32 instructions, the conflict
resolution for the new capability entries in arm64_features[]
inadvertedly predicated the availability of the CRC32 instructions on
CONFIG_ARM64_SSBD, despite the functionality being entirely unrelated.

Move the #ifdef CONFIG_ARM64_SSBD down so that it only covers the SSBD
capability.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Pull GPIO fixes from Linus Walleij:
 "Minor stuff except the IDA leak which was kind of important to fix.
  Also new maintainers, yay.

   - Do not lose an IDA on the gpiochip register errorpath.

   - Fix the PXA non-pincontrol GPIO-using platforms.

   - Fix the direction on the mockup GPIO driver.

   - Add some MAINTAINERS stuff: Bartosz stepped up as GPIO
     co-maintainer, and Andy established an Intel git tree"

* tag 'gpio-v4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  MAINTAINERS: Do maintain Intel GPIO drivers via separate tree
  gpio: mockup: fix indicated direction
  gpio: pxa: fix legacy non pinctrl aware builds again
  gpio: don't free unallocated ida on gpiochip_add_data_with_key() error path
  MAINTAINERS: add myself as co-maintainer of gpiolib

Pull MMC fixes from Ulf Hansson:
 "MMC host:

   - sdhci-pci: Fixup card detect lookup

   - sdhci-pci: Workaround GLK firmware bug for tuning"

* tag 'mmc-v4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-pci: Workaround GLK firmware failing to restore the tuning value
  mmc: sdhci-pci: Try "cd" for card-detect lookup before using NULL

Pull drm fixes from Dave Airlie:
 "Regular drm fixes:

  amdgpu:
   - Vega20 fixes
   - firmware loading fix
   - panel display fix
   - override fix

  i915:
   - Sandybridge lockup fix
   - fastboot DSI panel fix
   - GPU hang on Broxton
   - GPU reloc fixes on pineview/bearlake

  ast:
   - screen blurring fix
   - cursor appearance fix

  udmabuf:
   - mmap fix

  vc4:
   - NULL deref fix
   - async cursor update fix

  All seems pretty normal at this stage"

* tag 'drm-fixes-2018-11-23' of git://anongit.freedesktop.org/drm/drm:
  drm/ast: fixed cursor may disappear sometimes
  drm/ast: change resolution may cause screen blurred
  drm/i915: Add rotation readout for plane initial config
  drm/i915: Force a LUT update in intel_initial_commit()
  drm/fb-helper: Blacklist writeback when adding connectors to fbdev
  drm/i915: Write GPU relocs harder with gen3
  drm/amdgpu: Enable HDP memory light sleep
  drm/i915: Prevent machine hang from Broxton's vtd w/a and error capture
  drm/amd/pp: handle negative values when reading OD
  drm/amdgpu: Add missing firmware entry for HAINAN
  drm/amd/powerplay: disable Vega20 DS related features
  drm/amdgpu: Fix oops when pp_funcs->switch_power_profile is unset
  drm/i915: Disable LP3 watermarks on all SNB machines
  drm/ast: Remove existing framebuffers before loading driver
  udmabuf: set read/write flag when exporting
  drm/amd/display: Support amdgpu "max bpc" connector property (v2)
  drm/amdgpu: Add amdgpu "max bpc" connector property (v2)
  drm/vc4: Set ->legacy_cursor_update to false when doing non-async updates
  drm/vc4: Fix NULL pointer dereference in the async update path

Specify correct type for the constants to avoid
the following sparse complaints:

./arch/arm64/include/asm/sysreg.h:471:42: warning: constant 0xffffffffffffffff is so big it is unsigned long
./arch/arm64/include/asm/sysreg.h:512:42: warning: constant 0xffffffffffffffff is so big it is unsigned long
Acked-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NOlof Johansson <olof@lixom.net>
Acked-by: NLuc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: NSergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

* pm-cpufreq:
  cpufreq: ti-cpufreq: Only register platform_device when supported

* pm-sleep:
  exec: make de_thread() freezable

* pm-opp:
  opp: ti-opp-supply: Correct the supply in _get_optimal_vdd_voltage call
  opp: ti-opp-supply: Dynamically update u_volt_min

* pm-tools:
  tools cpupower: Override CFLAGS assignments
  tools cpupower debug: Allow to use outside build flags
  tools/power/cpupower: fix compilation with STATIC=true