To change the active state of an MMIO, halt is requested for all vcpus of
the affected guest before modifying the IRQ state. This is done by calling
cond_resched_lock() in vgic_mmio_change_active(). However interrupts are
disabled at this point and we cannot reschedule a vcpu.

We actually don't need any of this, as kvm_arm_halt_guest ensures that
all the other vcpus are out of the guest. Let's just drop that useless
code.
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Suggested-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

KVM only supports PMD hugepages at stage 2. Now that the various page
handling routines are updated, extend the stage 2 fault handling to
map in PUD hugepages.

Addition of PUD hugepage support enables additional page sizes (e.g.,
1G with 4K granule) which can be useful on cores that support mapping
larger block sizes in the TLB entries.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[ Replace BUG() => WARN_ON(1) for arm32 PUD helpers ]
Signed-off-by: Suzuki Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

In preparation for creating larger hugepages at Stage 2, add support
to the age handling notifiers for PUD hugepages when encountered.

Provide trivial helpers for arm32 to allow sharing code.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[ Replaced BUG() => WARN_ON(1) for arm32 PUD helpers ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

In preparation for creating larger hugepages at Stage 2, extend the
access fault handling at Stage 2 to support PUD hugepages when
encountered.

Provide trivial helpers for arm32 to allow sharing of code.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[ Replaced BUG() => WARN_ON(1) in PUD helpers ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

In preparation for creating PUD hugepages at stage 2, add support for
detecting execute permissions on PUD page table entries. Faults due to
lack of execute permissions on page table entries is used to perform
i-cache invalidation on first execute.

Provide trivial implementations of arm32 helpers to allow sharing of
code.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[ Replaced BUG() => WARN_ON(1) in arm32 PUD helpers ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

In preparation for creating PUD hugepages at stage 2, add support for
write protecting PUD hugepages when they are encountered. Write
protecting guest tables is used to track dirty pages when migrating
VMs.

Also, provide trivial implementations of required kvm_s2pud_* helpers
to allow sharing of code with arm32.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[ Replaced BUG() => WARN_ON() in arm32 pud helpers ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Introduce helpers to abstract architectural handling of the conversion
of pfn to page table entries and marking a PMD page table entry as a
block entry.

The helpers are introduced in preparation for supporting PUD hugepages
at stage 2 - which are supported on arm64 but do not exist on arm.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Stage 2 fault handler marks a page as executable if it is handling an
execution fault or if it was a permission fault in which case the
executable bit needs to be preserved.

The logic to decide if the page should be marked executable is
duplicated for PMD and PTE entries. To avoid creating another copy
when support for PUD hugepages is introduced refactor the code to
share the checks needed to mark a page table entry as executable.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

The code for operations such as marking the pfn as dirty, and
dcache/icache maintenance during stage 2 fault handling is duplicated
between normal pages and PMD hugepages.

Instead of creating another copy of the operations when we introduce
PUD hugepages, let's share them across the different pagesizes.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When restoring the active state from userspace, we don't know which CPU
was the source for the active state, and this is not architecturally
exposed in any of the register state.

Set the active_source to 0 in this case.  In the future, we can expand
on this and exposse the information as additional information to
userspace for GICv2 if anyone cares.

Cc: stable@vger.kernel.org
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When KVM traps an unhandled sysreg/coproc access from a guest, it logs
the guest PC. To aid debugging, it would be helpful to know which
exception level the trap came from, along with other PSTATE/CPSR bits,
so let's log the PSTATE/CPSR too.
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

We recently addressed a VMID generation race by introducing a read/write
lock around accesses and updates to the vmid generation values.

However, kvm_arch_vcpu_ioctl_run() also calls need_new_vmid_gen() but
does so without taking the read lock.

As far as I can tell, this can lead to the same kind of race:

  VM 0, VCPU 0			VM 0, VCPU 1
  ------------			------------
  update_vttbr (vmid 254)
  				update_vttbr (vmid 1) // roll over
				read_lock(kvm_vmid_lock);
				force_vm_exit()
  local_irq_disable
  need_new_vmid_gen == false //because vmid gen matches

  enter_guest (vmid 254)
  				kvm_arch.vttbr = <PGD>:<VMID 1>
				read_unlock(kvm_vmid_lock);

  				enter_guest (vmid 1)

Which results in running two VCPUs in the same VM with different VMIDs
and (even worse) other VCPUs from other VMs could now allocate clashing
VMID 254 from the new generation as long as VCPU 0 is not exiting.

Attempt to solve this by making sure vttbr is updated before another CPU
can observe the updated VMID generation.

Cc: stable@vger.kernel.org
Fixes: f0cf47d9 "KVM: arm/arm64: Close VMID generation race"
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When we emulate a guest instruction, we don't advance the hardware
singlestep state machine, and thus the guest will receive a software
step exception after a next instruction which is not emulated by the
host.

We bodge around this in an ad-hoc fashion. Sometimes we explicitly check
whether userspace requested a single step, and fake a debug exception
from within the kernel. Other times, we advance the HW singlestep state
rely on the HW to generate the exception for us. Thus, the observed step
behaviour differs for host and guest.

Let's make this simpler and consistent by always advancing the HW
singlestep state machine when we skip an instruction. Thus we can rely
on the hardware to generate the singlestep exception for us, and never
need to explicitly check for an active-pending step, nor do we need to
fake a debug exception from the guest.

Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When we emulate an MMIO instruction, we advance the CPU state within
decode_hsr(), before emulating the instruction effects.

Having this logic in decode_hsr() is opaque, and advancing the state
before emulation is problematic. It gets in the way of applying
consistent single-step logic, and it prevents us from being able to fail
an MMIO instruction with a synchronous exception.

Clean this up by only advancing the CPU state *after* the effects of the
instruction are emulated.

Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.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: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Linus 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: Andreas Fiedler <andreas.fiedler@gmx.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David 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: Quentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

The correct form is "can be probed", so fix the typo.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David 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: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David 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: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: David 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: Liang Li <liali@redhat.com>
Fixes: fc423ff0 ("team: add peer notification")
Fixes: 492b200e ("team: add support for sending multicast rejoins")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David 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: Jesper 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: Jason Wang <jasowang@redhat.com>
Signed-off-by: David 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: Jesper 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: Jason Wang <jasowang@redhat.com>
Signed-off-by: David 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: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David 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: Eric Dumazet <eric.dumazet@gmail.com>
Fixes: 3b47d303 ("net: gro: add a per device gro flush timer")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David 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: Jianlin Shi <jishi@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David 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: Anand H. Krishnan <anandhkrishnan@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David 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