Non-cryptographic PRNGs may have great statistical properties, but
are usually trivially predictable to someone who knows the algorithm,
given a small sample of their output.  An LFSR like prandom_u32() is
particularly simple, even if the sample is widely scattered bits.

It turns out the network stack uses prandom_u32() for some things like
random port numbers which it would prefer are *not* trivially predictable.
Predictability led to a practical DNS spoofing attack.  Oops.

This patch replaces the LFSR with a homebrew cryptographic PRNG based
on the SipHash round function, which is in turn seeded with 128 bits
of strong random key.  (The authors of SipHash have *not* been consulted
about this abuse of their algorithm.)  Speed is prioritized over security;
attacks are rare, while performance is always wanted.

Replacing all callers of prandom_u32() is the quick fix.
Whether to reinstate a weaker PRNG for uses which can tolerate it
is an open question.

Commit f227e3ec ("random32: update the net random state on interrupt
and activity") was an earlier attempt at a solution.  This patch replaces
it.
Reported-by: Amit Klein <aksecurity@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tytso@mit.edu
Cc: Florian Westphal <fw@strlen.de>
Cc: Marc Plumb <lkml.mplumb@gmail.com>
Fixes: f227e3ec ("random32: update the net random state on interrupt and activity")
Signed-off-by: George Spelvin <lkml@sdf.org>
Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/
[ willy: partial reversal of f227e3ec; moved SIPROUND definitions
  to prandom.h for later use; merged George's prandom_seed() proposal;
  inlined siprand_u32(); replaced the net_rand_state[] array with 4
  members to fix a build issue; cosmetic cleanups to make checkpatch
  happy; fixed RANDOM32_SELFTEST build ]
Signed-off-by: Willy Tarreau <w@1wt.eu>

Pull xfs fixes from Darrick Wong:
 "Two bug fixes that trickled in during the merge window:

   - Make fallocate check the alignment of its arguments against the
     fundamental allocation unit of the volume the file lives on, so
     that we don't trigger the fs' alignment checks.

   - Cancel unprocessed log intents immediately when log recovery fails,
     to avoid a log deadlock"

* tag 'xfs-5.10-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: cancel intents immediately if process_intents fails
  xfs: fix fallocate functions when rtextsize is larger than 1

Pull documentation fixes from Jonathan Corbet:
 "A handful of late-arriving documentation fixes"

* tag 'docs-5.10-2' of git://git.lwn.net/linux:
  docs: Add two missing entries in vm sysctl index
  docs/vm: trivial fixes to several spelling mistakes
  docs: submitting-patches: describe preserving review/test tags
  Documentation: Chinese translation of Documentation/arm64/hugetlbpage.rst
  Documentation: x86: fix a missing word in x86_64/mm.rst.
  docs: driver-api: remove a duplicated index entry
  docs: lkdtm: Modernize and improve details
  docs: deprecated.rst: Expand str*cpy() replacement notes
  docs/cpu-load: format the example code.

Pull tracing ring-buffer fix from Steven Rostedt:
 "The success return value of ring_buffer_resize() is stated to be
  zero and checked that way.

  But it was incorrectly returning the size allocated.

  Also, a fix to a comment"

* tag 'trace-v5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Update the description for ring_buffer_wait
  ring-buffer: Return 0 on success from ring_buffer_resize()

Pull more ACPI updates from Rafael Wysocki:
 "These include an ACPICA code build fix related to recent GPE register
  access changes, a Kconfig cleanup related to the Dynamic Platform and
  Thremal Framework (DPTF) support, a reboot issue workaround, a debug
  module fix and a couple of janitorial changes.

  Specifics:

   - Fix ACPICA code build after recent changes related to accessing GPE
     registers (Rafael Wysocki).

   - Clean up DPTF part of the ACPI Kconfig (Rafael Wysocki).

   - Work around a reboot issue related to RESET_REG (Zhang Rui).

   - Prevent ACPI debug module from attemtping to run (and crashing)
     when ACPI is disabled (Jamie Iles).

   - Drop confusing comment from the ACPI processor driver (Alex Hung).

   - Drop a few unreachable break statements (Tom Rix)"

* tag 'acpi-5.10-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: utils: remove unreachable breaks
  ACPICA: Add missing type casts in GPE register access code
  ACPI: DPTF: Add ACPI_DPTF Kconfig menu
  ACPI: DPTF: Fix participant driver names
  ACPI: processor: remove comment regarding string _UID support
  ACPI: reboot: Avoid racing after writing to ACPI RESET_REG
  ACPI: debug: don't allow debugging when ACPI is disabled

Pull more power management updates from Rafael Wysocki:
 "First of all, the adaptive voltage scaling (AVS) drivers go to new
  platform-specific locations as planned (this part was reported to have
  merge conflicts against the new arm-soc updates in linux-next).

  In addition to that, there are some fixes (intel_idle, intel_pstate,
  RAPL, acpi_cpufreq), the addition of on/off notifiers and idle state
  accounting support to the generic power domains (genpd) code and some
  janitorial changes all over.

  Specifics:

   - Move the AVS drivers to new platform-specific locations and get rid
     of the drivers/power/avs directory (Ulf Hansson).

   - Add on/off notifiers and idle state accounting support to the
     generic power domains (genpd) framework (Ulf Hansson, Lina Iyer).

   - Ulf will maintain the PM domain part of cpuidle-psci (Ulf Hansson).

   - Make intel_idle disregard ACPI _CST if it cannot use the data
     returned by that method (Mel Gorman).

   - Modify intel_pstate to avoid leaving useless sysfs directory
     structure behind if it cannot be registered (Chen Yu).

   - Fix domain detection in the RAPL power capping driver and prevent
     it from failing to enumerate the Psys RAPL domain (Zhang Rui).

   - Allow acpi-cpufreq to use ACPI _PSD information with Family 19 and
     later AMD chips (Wei Huang).

   - Update the driver assumptions comment in intel_idle and fix a
     kerneldoc comment in the runtime PM framework (Alexander Monakov,
     Bean Huo).

   - Avoid unnecessary resets of the cached frequency in the schedutil
     cpufreq governor to reduce overhead (Wei Wang).

   - Clean up the cpufreq core a bit (Viresh Kumar).

   - Make assorted minor janitorial changes (Daniel Lezcano, Geert
     Uytterhoeven, Hubert Jasudowicz, Tom Rix).

   - Clean up and optimize the cpupower utility somewhat (Colin Ian
     King, Martin Kaistra)"

* tag 'pm-5.10-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (23 commits)
  PM: sleep: remove unreachable break
  PM: AVS: Drop the avs directory and the corresponding Kconfig
  PM: AVS: qcom-cpr: Move the driver to the qcom specific drivers
  PM: runtime: Fix typo in pm_runtime_set_active() helper comment
  PM: domains: Fix build error for genpd notifiers
  powercap: Fix typo in Kconfig "Plance" -> "Plane"
  cpufreq: schedutil: restore cached freq when next_f is not changed
  acpi-cpufreq: Honor _PSD table setting on new AMD CPUs
  PM: AVS: smartreflex Move driver to soc specific drivers
  PM: AVS: rockchip-io: Move the driver to the rockchip specific drivers
  PM: domains: enable domain idle state accounting
  PM: domains: Add curly braces to delimit comment + statement block
  PM: domains: Add support for PM domain on/off notifiers for genpd
  powercap/intel_rapl: enumerate Psys RAPL domain together with package RAPL domain
  powercap/intel_rapl: Fix domain detection
  intel_idle: Ignore _CST if control cannot be taken from the platform
  cpuidle: Remove pointless stub
  intel_idle: mention assumption that WBINVD is not needed
  MAINTAINERS: Add section for cpuidle-psci PM domain
  cpufreq: intel_pstate: Delete intel_pstate sysfs if failed to register the driver
  ...

Pull more SCSI updates from James Bottomley:
 "The set of core changes here is Christoph's submission path cleanups.

  These introduced a couple of regressions when first proposed so they
  got held over from the initial merge window pull request to give more
  testing time, which they've now had and Syzbot has confirmed the
  regression it detected is fixed.

  The other main changes are two driver updates (arcmsr, pm80xx) and
  assorted minor clean ups"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (38 commits)
  scsi: qla2xxx: Fix return of uninitialized value in rval
  scsi: core: Set sc_data_direction to DMA_NONE for no-transfer commands
  scsi: sr: Initialize ->cmd_len
  scsi: arcmsr: Update driver version to v1.50.00.02-20200819
  scsi: arcmsr: Add support for ARC-1886 series RAID controllers
  scsi: arcmsr: Fix device hot-plug monitoring timer stop
  scsi: arcmsr: Remove unnecessary syntax
  scsi: pm80xx: Driver version update
  scsi: pm80xx: Increase the number of outstanding I/O supported to 1024
  scsi: pm80xx: Remove DMA memory allocation for ccb and device structures
  scsi: pm80xx: Increase number of supported queues
  scsi: sym53c8xx_2: Fix sizeof() mismatch
  scsi: isci: Fix a typo in a comment
  scsi: qla4xxx: Fix inconsistent format argument type
  scsi: myrb: Fix inconsistent format argument types
  scsi: myrb: Remove redundant assignment to variable timeout
  scsi: bfa: Fix error return in bfad_pci_init()
  scsi: fcoe: Simplify the return expression of fcoe_sysfs_setup()
  scsi: snic: Simplify the return expression of svnic_cq_alloc()
  scsi: fnic: Simplify the return expression of vnic_wq_copy_alloc()
  ...

Pull input updates from Dmitry Torokhov:

 - a new driver for ADC driven joysticks

 - a new Zintix touchscreen driver

 - enhancements to Intel SoC button array driver

 - support for F3A "function" in Synaptics RMI4 driver

 - assorted driver fixups

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (29 commits)
  Input: Add MAINTAINERS entry for SiS i2c touch input driver
  Input: evdev - per-client waitgroups
  Input: synaptics - enable InterTouch for ThinkPad T14 Gen 1
  Input: synaptics - enable InterTouch for ThinkPad P1/X1E gen 2
  Input: synaptics-rmi4 - support bootloader v8 in f34v7
  Input: synaptics-rmi4 - add support for F3A
  Input: synaptics-rmi4 - rename f30_data to gpio_data
  Input: add zinitix touchscreen driver
  dt-bindings: input/touchscreen: add bindings for zinitix
  Input: joystick - add ADC attached joystick driver.
  dt-bindings: input: Add docs for ADC driven joystick
  Input: sun4i-ps2 - fix handling of platform_get_irq() error
  Input: twl4030_keypad - fix handling of platform_get_irq() error
  Input: omap4-keypad - fix handling of platform_get_irq() error
  Input: ep93xx_keypad - fix handling of platform_get_irq() error
  Input: stmfts - fix a & vs && typo
  Input: imx6ul_tsc - unify open/close and PM paths
  Input: imx6ul_tsc - clean up some errors in imx6ul_tsc_resume()
  Input: elants_i2c - fix typo for an attribute to show calibration count
  Input: elants_i2c - report resolution of ABS_MT_TOUCH_MAJOR by FW information.
  ...

Pull sound fixes from Takashi Iwai:
 "Just a few additional small and trivial fixes"

* tag 'sound-fix-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Fix the return value if cb func is already registered
  ALSA: usb-audio: Line6 Pod Go interface requires static clock rate quirk
  ALSA: hda/ca0132: make some const arrays static, makes object smaller
  ALSA: sparc: dbri: fix repeated word 'the'

Pull more drm fixes from Dave Airlie:
 "This should be the last round of things for rc1, a bunch of i915
  fixes, some amdgpu, more font OOB fixes and one ttm fix just found
  reading code:

  fbcon/fonts:
   - Two patches to prevent OOB access

  ttm:
   - fix for evicition value range check

  amdgpu:
   - Sienna Cichlid fixes
   - MST manager resource leak fix
   - GPU reset fix

  amdkfd:
   - Luxmark fix for Navi1x

  i915:
   - Tweak initial DPCD backlight.enabled value (Sean)
   - Initialize reserved MOCS indices (Ayaz)
   - Mark initial fb obj as WT on eLLC machines to avoid rcu lockup (Ville)
   - Support parsing of oversize batches (Chris)
   - Delay execlists processing for TGL (Chris)
   - Use the active reference on the vma during error capture (Chris)
   - Widen CSB pointer (Chris)
   - Wait for CSB entries on TGL (Chris)
   - Fix unwind for scratch page allocation (Chris)
   - Exclude low patches of stolen memory (Chris)
   - Force VT'd workarounds when running as a guest OS (Chris)
   - Drop runtime-pm assert from vpgu io accessors (Chris)"

* tag 'drm-next-2020-10-23' of git://anongit.freedesktop.org/drm/drm: (31 commits)
  drm/amdgpu: correct the cu and rb info for sienna cichlid
  drm/amd/pm: remove the average clock value in sysfs
  drm/amd/pm: fix pp_dpm_fclk
  Revert drm/amdgpu: disable sienna chichlid UMC RAS
  drm/amd/pm: fix pcie information for sienna cichlid
  drm/amdkfd: Use same SQ prefetch setting as amdgpu
  drm/amd/swsmu: correct wrong feature bit mapping
  drm/amd/psp: Fix sysfs: cannot create duplicate filename
  drm/amd/display: Avoid MST manager resource leak.
  drm/amd/display: Revert "drm/amd/display: Fix a list corruption"
  drm/amdgpu: update golden setting for sienna_cichlid
  drm/amd/swsmu: add missing feature map for sienna_cichlid
  drm/amdgpu: correct the gpu reset handling for job != NULL case
  drm/amdgpu: add rlc iram and dram firmware support
  drm/amdgpu: add function to program pbb mode for sienna cichlid
  drm/i915: Drop runtime-pm assert from vgpu io accessors
  drm/i915: Force VT'd workarounds when running as a guest OS
  drm/i915: Exclude low pages (128KiB) of stolen from use
  drm/i915/gt: Onion unwind for scratch page allocation failure
  drm/ttm: fix eviction valuable range check.
  ...

Quoting https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html:

  You can define a local register variable and associate it with a
  specified register...

  The only supported use for this feature is to specify registers for
  input and output operands when calling Extended asm (see Extended
  Asm). This may be necessary if the constraints for a particular
  machine don't provide sufficient control to select the desired
  register.

On 32-bit x86, this is used to ensure that gcc will put an 8-byte value
into the %edx:%eax pair, while all other cases will just use the single
register %eax (%rax on x86-64).  While the _ASM_AX actually just expands
to "%eax", note this comment next to get_user() which does something
very similar:

 * The use of _ASM_DX as the register specifier is a bit of a
 * simplification, as gcc only cares about it as the starting point
 * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits
 * (%ecx being the next register in gcc's x86 register sequence), and
 * %rdx on 64 bits.

However, getting this to work requires that there is no code between the
assignment to the local register variable and its use as an input to the
asm() which can possibly clobber any of the registers involved -
including evaluation of the expressions making up other inputs.

In the current code, the ptr expression used directly as an input may
cause such code to be emitted.  For example, Sean Christopherson
observed that with KASAN enabled and ptr being current->set_child_tid
(from chedule_tail()), the load of current->set_child_tid causes a call
to __asan_load8() to be emitted immediately prior to the __put_user_4
call, and Naresh Kamboju reports that various mmstress tests fail on
KASAN-enabled builds.

It's also possible to synthesize a broken case without KASAN if one uses
"foo()" as the ptr argument, with foo being some "extern u64 __user
*foo(void);" (though I don't know if that appears in real code).

Fix it by making sure ptr gets evaluated before the assignment to
__val_pu, and add a comment that __val_pu must be the last thing
computed before the asm() is entered.

Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: d55564cf ("x86: Make __put_user() generate an out-of-line call")
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull networking fixes from Jakub Kicinski:
 "Cross-tree/merge window issues:

   - rtl8150: don't incorrectly assign random MAC addresses; fix late in
     the 5.9 cycle started depending on a return code from a function
     which changed with the 5.10 PR from the usb subsystem

  Current release regressions:

   - Revert "virtio-net: ethtool configurable RXCSUM", it was causing
     crashes at probe when control vq was not negotiated/available

  Previous release regressions:

   - ixgbe: fix probing of multi-port 10 Gigabit Intel NICs with an MDIO
     bus, only first device would be probed correctly

   - nexthop: Fix performance regression in nexthop deletion by
     effectively switching from recently added synchronize_rcu() to
     synchronize_rcu_expedited()

   - netsec: ignore 'phy-mode' device property on ACPI systems; the
     property is not populated correctly by the firmware, but firmware
     configures the PHY so just keep boot settings

  Previous releases - always broken:

   - tcp: fix to update snd_wl1 in bulk receiver fast path, addressing
     bulk transfers getting "stuck"

   - icmp: randomize the global rate limiter to prevent attackers from
     getting useful signal

   - r8169: fix operation under forced interrupt threading, make the
     driver always use hard irqs, even on RT, given the handler is light
     and only wants to schedule napi (and do so through a _irqoff()
     variant, preferably)

   - bpf: Enforce pointer id generation for all may-be-null register
     type to avoid pointers erroneously getting marked as null-checked

   - tipc: re-configure queue limit for broadcast link

   - net/sched: act_tunnel_key: fix OOB write in case of IPv6 ERSPAN
     tunnels

   - fix various issues in chelsio inline tls driver

  Misc:

   - bpf: improve just-added bpf_redirect_neigh() helper api to support
     supplying nexthop by the caller - in case BPF program has already
     done a lookup we can avoid doing another one

   - remove unnecessary break statements

   - make MCTCP not select IPV6, but rather depend on it"

* tag 'net-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (62 commits)
  tcp: fix to update snd_wl1 in bulk receiver fast path
  net: Properly typecast int values to set sk_max_pacing_rate
  netfilter: nf_fwd_netdev: clear timestamp in forwarding path
  ibmvnic: save changed mac address to adapter->mac_addr
  selftests: mptcp: depends on built-in IPv6
  Revert "virtio-net: ethtool configurable RXCSUM"
  rtnetlink: fix data overflow in rtnl_calcit()
  net: ethernet: mtk-star-emac: select REGMAP_MMIO
  net: hdlc_raw_eth: Clear the IFF_TX_SKB_SHARING flag after calling ether_setup
  net: hdlc: In hdlc_rcv, check to make sure dev is an HDLC device
  bpf, libbpf: Guard bpf inline asm from bpf_tail_call_static
  bpf, selftests: Extend test_tc_redirect to use modified bpf_redirect_neigh()
  bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop
  mptcp: depends on IPV6 but not as a module
  sfc: move initialisation of efx->filter_sem to efx_init_struct()
  mpls: load mpls_gso after mpls_iptunnel
  net/sched: act_tunnel_key: fix OOB write in case of IPv6 ERSPAN tunnels
  net/sched: act_gate: Unlock ->tcfa_lock in tc_setup_flow_action()
  net: dsa: bcm_sf2: make const array static, makes object smaller
  mptcp: MPTCP_IPV6 should depend on IPV6 instead of selecting it
  ...

Pull gfs2 updates from Andreas Gruenbacher:

 - Use iomap for non-journaled buffered I/O. This largely eliminates
   buffer heads on filesystems where the block size matches the page
   size. Many thanks to Christoph Hellwig for this patch!

 - Fixes for some more journaled data filesystem bugs, found by running
   xfstests with data journaling on for all files (chattr +j $MNT) (Bob
   Peterson)

 - gfs2_evict_inode refactoring (Bob Peterson)

 - Use the statfs data in the journal during recovery instead of reading
   it in from the local statfs inodes (Abhi Das)

 - Several other minor fixes by various people

* tag 'gfs2-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (30 commits)
  gfs2: Recover statfs info in journal head
  gfs2: lookup local statfs inodes prior to journal recovery
  gfs2: Add fields for statfs info in struct gfs2_log_header_host
  gfs2: Ignore subsequent errors after withdraw in rgrp_go_sync
  gfs2: Eliminate gl_vm
  gfs2: Only access gl_delete for iopen glocks
  gfs2: Fix comments to glock_hash_walk
  gfs2: eliminate GLF_QUEUED flag in favor of list_empty(gl_holders)
  gfs2: Ignore journal log writes for jdata holes
  gfs2: simplify gfs2_block_map
  gfs2: Only set PageChecked if we have a transaction
  gfs2: don't lock sd_ail_lock in gfs2_releasepage
  gfs2: make gfs2_ail1_empty_one return the count of active items
  gfs2: Wipe jdata and ail1 in gfs2_journal_wipe, formerly gfs2_meta_wipe
  gfs2: enhance log_blocks trace point to show log blocks free
  gfs2: add missing log_blocks trace points in gfs2_write_revokes
  gfs2: rename gfs2_write_full_page to gfs2_write_jdata_page, remove parm
  gfs2: add validation checks for size of superblock
  gfs2: use-after-free in sysfs deregistration
  gfs2: Fix NULL pointer dereference in gfs2_rgrp_dump
  ...

Pull cifs updates from Steve French:

 - add support for recognizing special file types (char/block/fifo/
   symlink) for files created by Linux on WSL (a format we plan to move
   to as the default for creating special files on Linux, as it has
   advantages over the other current option, the SFU format) in readdir.

 - fix double queries to root directory when directory leases not
   supported (e.g. Samba)

 - fix querying mode bits (modefromsid mount option) for special file
   types

 - stronger encryption (gcm256), disabled by default until tested more
   broadly

 - allow querying owner when server reports 'well known SID' on query
   dir with SMB3.1.1 POSIX extensions

* tag '5.10-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6: (30 commits)
  SMB3: add support for recognizing WSL reparse tags
  cifs: remove bogus debug code
  smb3.1.1: fix typo in compression flag
  cifs: move smb version mount options into fs_context.c
  cifs: move cache mount options to fs_context.ch
  cifs: move security mount options into fs_context.ch
  cifs: add files to host new mount api
  smb3: do not try to cache root directory if dir leases not supported
  smb3: fix stat when special device file and mounted with modefromsid
  cifs: Print the address and port we are connecting to in generic_ip_connect()
  SMB3: Resolve data corruption of TCP server info fields
  cifs: make const array static, makes object smaller
  SMB3.1.1: Fix ids returned in POSIX query dir
  smb3: add dynamic trace point to trace when credits obtained
  smb3.1.1: do not fail if no encryption required but server doesn't support it
  cifs: Return the error from crypt_message when enc/dec key not found.
  smb3.1.1: set gcm256 when requested
  smb3.1.1: rename nonces used for GCM and CCM encryption
  smb3.1.1: print warning if server does not support requested encryption type
  smb3.1.1: add new module load parm enable_gcm_256
  ...

Pull clone/dedupe/remap code refactoring from Darrick Wong:
 "Move the generic file range remap (aka reflink and dedupe) functions
  out of mm/filemap.c and fs/read_write.c and into fs/remap_range.c to
  reduce clutter in the first two files"

* tag 'vfs-5.10-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  vfs: move the generic write and copy checks out of mm
  vfs: move the remap range helpers to remap_range.c
  vfs: move generic_remap_checks out of mm

Pull KVM updates from Paolo Bonzini:
 "For x86, there is a new alternative and (in the future) more scalable
  implementation of extended page tables that does not need a reverse
  map from guest physical addresses to host physical addresses.

  For now it is disabled by default because it is still lacking a few of
  the existing MMU's bells and whistles. However it is a very solid
  piece of work and it is already available for people to hammer on it.

  Other updates:

  ARM:
   - New page table code for both hypervisor and guest stage-2
   - Introduction of a new EL2-private host context
   - Allow EL2 to have its own private per-CPU variables
   - Support of PMU event filtering
   - Complete rework of the Spectre mitigation

  PPC:
   - Fix for running nested guests with in-kernel IRQ chip
   - Fix race condition causing occasional host hard lockup
   - Minor cleanups and bugfixes

  x86:
   - allow trapping unknown MSRs to userspace
   - allow userspace to force #GP on specific MSRs
   - INVPCID support on AMD
   - nested AMD cleanup, on demand allocation of nested SVM state
   - hide PV MSRs and hypercalls for features not enabled in CPUID
   - new test for MSR_IA32_TSC writes from host and guest
   - cleanups: MMU, CPUID, shared MSRs
   - LAPIC latency optimizations ad bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (232 commits)
  kvm: x86/mmu: NX largepage recovery for TDP MMU
  kvm: x86/mmu: Don't clear write flooding count for direct roots
  kvm: x86/mmu: Support MMIO in the TDP MMU
  kvm: x86/mmu: Support write protection for nesting in tdp MMU
  kvm: x86/mmu: Support disabling dirty logging for the tdp MMU
  kvm: x86/mmu: Support dirty logging for the TDP MMU
  kvm: x86/mmu: Support changed pte notifier in tdp MMU
  kvm: x86/mmu: Add access tracking for tdp_mmu
  kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMU
  kvm: x86/mmu: Allocate struct kvm_mmu_pages for all pages in TDP MMU
  kvm: x86/mmu: Add TDP MMU PF handler
  kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator arg
  kvm: x86/mmu: Support zapping SPTEs in the TDP MMU
  KVM: Cache as_id in kvm_memory_slot
  kvm: x86/mmu: Add functions to handle changed TDP SPTEs
  kvm: x86/mmu: Allocate and free TDP MMU roots
  kvm: x86/mmu: Init / Uninit the TDP MMU
  kvm: x86/mmu: Introduce tdp_iter
  KVM: mmu: extract spte.h and spte.c
  KVM: mmu: Separate updating a PTE from kvm_set_pte_rmapp
  ...

Pull virtio updates from Michael Tsirkin:
 "vhost, vdpa, and virtio cleanups and fixes

  A very quiet cycle, no new features"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  MAINTAINERS: add URL for virtio-mem
  vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call
  vringh: fix __vringh_iov() when riov and wiov are different
  vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK
  s390: virtio: PV needs VIRTIO I/O device protection
  virtio: let arch advertise guest's memory access restrictions
  vhost_vdpa: Fix duplicate included kernel.h
  vhost: reduce stack usage in log_used
  virtio-mem: Constify mem_id_table
  virtio_input: Constify id_table
  virtio-balloon: Constify id_table
  vdpa/mlx5: Fix failure to bring link up
  vdpa/mlx5: Make use of a specific 16 bit endianness API

Merge tag 'tag-chrome-platform-for-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux

Pull chrome platform updates from Benson Leung:
 "cros-ec:
   - Error code cleanup across cros-ec by Guenter
   - Remove cros_ec_cmd_xfer in favor of cros_ec_cmd_xfer_status

  cros_ec_typec:
   - Landed initial USB4 support in typec connector class driver for
     cros_ec
   - Role switch bugfix on disconnect, and reordering configuration
     steps

  cros_ec_lightbar:
   - Fix buffer outsize and result for get_lightbar_version

  misc:
   - Remove config MFD_CROS_EC, now that transition from MFD is complete
   - Enable KEY_LEFTMETA in new location on arm based cros-ec-keyboard
     keymap"

* tag 'tag-chrome-platform-for-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux:
  ARM: dts: cros-ec-keyboard: Add alternate keymap for KEY_LEFTMETA
  platform/chrome: Use kobj_to_dev() instead of container_of()
  platform/chrome: cros_ec_proto: Drop cros_ec_cmd_xfer()
  platform/chrome: cros_ec_proto: Update cros_ec_cmd_xfer() call-sites
  platform/chrome: Kconfig: Remove the transitional MFD_CROS_EC config
  platform/chrome: cros_ec_lightbar: Reduce ligthbar get version command
  platform/chrome: cros_ec_trace: Add fields to command traces
  platform/chrome: cros_ec_typec: Re-order connector configuration steps
  platform/chrome: cros_ec_typec: Avoid setting usb role twice during disconnect
  platform/chrome: cros_ec_typec: Send enum values to usb_role_switch_set_role()
  platform/chrome: cros_ec_typec: USB4 support
  pwm: cros-ec: Simplify EC error handling
  platform/chrome: cros_ec_proto: Convert EC error codes to Linux error codes
  platform/input: cros_ec: Replace -ENOTSUPP with -ENOPROTOOPT
  pwm: cros-ec: Accept more error codes from cros_ec_cmd_xfer_status
  platform/chrome: cros_ec_sysfs: Report range of error codes from EC
  cros_ec_lightbar: Accept more error codes from cros_ec_cmd_xfer_status
  iio: cros_ec: Accept -EOPNOTSUPP as 'not supported' error code

Pull arch task_work cleanups from Jens Axboe:
 "Two cleanups that don't fit other categories:

   - Finally get the task_work_add() cleanup done properly, so we don't
     have random 0/1/false/true/TWA_SIGNAL confusing use cases. Updates
     all callers, and also fixes up the documentation for
     task_work_add().

   - While working on some TIF related changes for 5.11, this
     TIF_NOTIFY_RESUME cleanup fell out of that. Remove some arch
     duplication for how that is handled"

* tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block:
  task_work: cleanup notification modes
  tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()

Pull ARC fix from Vineet Gupta:
 "I found a snafu in perf driver which made it into 5.9-rc4 and the fix
  should go in now than wait"

* tag 'arc-5.10-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: perf: redo the pct irq missing in device-tree handling

Pull more arm64 updates from Will Deacon:
 "A small selection of further arm64 fixes and updates. Most of these
  are fixes that came in during the merge window, with the exception of
  the HAVE_MOVE_PMD mremap() speed-up which we discussed back in 2018
  and somehow forgot to enable upstream.

   - Improve performance of Spectre-v2 mitigation on Falkor CPUs (if
     you're lucky enough to have one)

   - Select HAVE_MOVE_PMD. This has been shown to improve mremap()
     performance, which is used heavily by the Android runtime GC, and
     it seems we forgot to enable this upstream back in 2018.

   - Ensure linker flags are consistent between LLVM and BFD

   - Fix stale comment in Spectre mitigation rework

   - Fix broken copyright header

   - Fix KASLR randomisation of the linear map

   - Prevent arm64-specific prctl()s from compat tasks (return -EINVAL)"

Link: https://lore.kernel.org/kvmarm/20181108181201.88826-3-joelaf@google.com/

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: proton-pack: Update comment to reflect new function name
  arm64: spectre-v2: Favour CPU-specific mitigation at EL2
  arm64: link with -z norelro regardless of CONFIG_RELOCATABLE
  arm64: Fix a broken copyright header in gen_vdso_offsets.sh
  arm64: mremap speedup - Enable HAVE_MOVE_PMD
  arm64: mm: use single quantity to represent the PA to VA translation
  arm64: reject prctl(PR_PAC_RESET_KEYS) on compat tasks

* acpi-debug:
  ACPI: debug: don't allow debugging when ACPI is disabled

* acpi-reboot:
  ACPI: reboot: Avoid racing after writing to ACPI RESET_REG

* acpi-processor:
  ACPI: processor: remove comment regarding string _UID support

* acpi-dptf:
  ACPI: DPTF: Add ACPI_DPTF Kconfig menu
  ACPI: DPTF: Fix participant driver names

* acpi-utils:
  ACPI: utils: remove unreachable breaks

* pm-avs:
  PM: AVS: Drop the avs directory and the corresponding Kconfig
  PM: AVS: qcom-cpr: Move the driver to the qcom specific drivers
  PM: AVS: smartreflex Move driver to soc specific drivers
  PM: AVS: rockchip-io: Move the driver to the rockchip specific drivers

* pm-core:
  PM: runtime: Fix typo in pm_runtime_set_active() helper comment

* pm-sleep:
  PM: sleep: remove unreachable break

* pm-tools:
  cpupower: speed up generating git version string
  cpupowerutils: fix spelling mistake "dependant" -> "dependent"

* powercap:
  powercap: Fix typo in Kconfig "Plance" -> "Plane"
  powercap/intel_rapl: enumerate Psys RAPL domain together with package RAPL domain
  powercap/intel_rapl: Fix domain detection

* pm-cpufreq:
  cpufreq: schedutil: restore cached freq when next_f is not changed
  acpi-cpufreq: Honor _PSD table setting on new AMD CPUs
  cpufreq: intel_pstate: Delete intel_pstate sysfs if failed to register the driver
  cpufreq: Improve code around unlisted freq check

* pm-cpuidle:
  intel_idle: Ignore _CST if control cannot be taken from the platform
  cpuidle: Remove pointless stub
  intel_idle: mention assumption that WBINVD is not needed
  MAINTAINERS: Add section for cpuidle-psci PM domain

Apply the outstanding statfs changes in the journal head to the
master statfs file. Zero out the local statfs file for good measure.

Previously, statfs updates would be read in from the local statfs inode and
synced to the master statfs inode during recovery.

We now use the statfs updates in the journal head to update the master statfs
inode instead of reading in from the local statfs inode. To preserve backward
compatibility with kernels that can't do this, we still need to keep the
local statfs inode up to date by writing changes to it. At some point in the
future, we can do away with the local statfs inodes altogether and keep the
statfs changes solely in the journal.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

We need to lookup the master statfs inode and the local statfs
inodes earlier in the mount process (in init_journal) so journal
recovery can use them when it attempts to recover the statfs info.
We lookup all the local statfs inodes and store them in a linked
list to allow a node to recover statfs info for other nodes in the
cluster.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

When KVM maps a largepage backed region at a lower level in order to
make it executable (i.e. NX large page shattering), it reduces the TLB
performance of that region. In order to avoid making this degradation
permanent, KVM must periodically reclaim shattered NX largepages by
zapping them and allowing them to be rebuilt in the page fault handler.

With this patch, the TDP MMU does not respect KVM's rate limiting on
reclaim. It traverses the entire TDP structure every time. This will be
addressed in a future patch.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-21-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Direct roots don't have a write flooding count because the guest can't
affect that paging structure. Thus there's no need to clear the write
flooding count on a fast CR3 switch for direct roots.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-20-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In order to support MMIO, KVM must be able to walk the TDP paging
structures to find mappings for a given GFN. Support this walk for
the TDP MMU.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538

v2: Thanks to Dan Carpenter and kernel test robot for finding that root
was used uninitialized in get_mmio_spte.
Signed-off-by: Ben Gardon <bgardon@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Message-Id: <20201014182700.2888246-19-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

To support nested virtualization, KVM will sometimes need to write
protect pages which are part of a shadowed paging structure or are not
writable in the shadowed paging structure. Add a function to write
protect GFN mappings for this purpose.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-18-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Dirty logging ultimately breaks down MMU mappings to 4k granularity.
When dirty logging is no longer needed, these granaular mappings
represent a useless performance penalty. When dirty logging is disabled,
search the paging structure for mappings that could be re-constituted
into a large page mapping. Zap those mappings so that they can be
faulted in again at a higher mapping level.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-17-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Dirty logging is a key feature of the KVM MMU and must be supported by
the TDP MMU. Add support for both the write protection and PML dirty
logging modes.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-16-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In order to interoperate correctly with the rest of KVM and other Linux
subsystems, the TDP MMU must correctly handle various MMU notifiers. Add
a hook and handle the change_pte MMU notifier.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-15-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In order to interoperate correctly with the rest of KVM and other Linux
subsystems, the TDP MMU must correctly handle various MMU notifiers. The
main Linux MM uses the access tracking MMU notifiers for swap and other
features. Add hooks to handle the test/flush HVA (range) family of
MMU notifiers.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-14-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In order to interoperate correctly with the rest of KVM and other Linux
subsystems, the TDP MMU must correctly handle various MMU notifiers. Add
hooks to handle the invalidate range family of MMU notifiers.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-13-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Attach struct kvm_mmu_pages to every page in the TDP MMU to track
metadata, facilitate NX reclaim, and enable inproved parallelism of MMU
operations in future patches.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-12-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Add functions to handle page faults in the TDP MMU. These page faults
are currently handled in much the same way as the x86 shadow paging
based MMU, however the ordering of some operations is slightly
different. Future patches will add eager NX splitting, a fast page fault
handler, and parallel page faults.

Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell
machine. This series introduced no new failures.

This series can be viewed in Gerrit at:
	https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20201014182700.2888246-11-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'drm-intel-next-fixes-2020-10-22' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

- Tweak initia DPCD backlight.enabled value (Sean)
- Initialize reserved MOCS indices (Ayaz)
- Mark initial fb obj as WT on eLLC machines to avoid rcu lockup (Ville)
- Support parsing of oversize batches (Chris)
- Delay execlists processing for TGL (Chris)
- Use the active reference on the vma during error capture (Chris)
- Widen CSB pointer (Chris)
- Wait for CSB entries on TGL (Chris)
- Fix unwind for scratch page allocation (Chris)
- Exclude low patches of stolen memory (Chris)
- Force VT'd workarounds when running as a guest OS (Chris)
- Drop runtime-pm assert from vpgu io accessors (Chris)
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201022205613.GA3469192@intel.com

Merge tag 'amd-drm-fixes-5.10-2020-10-21' of git://people.freedesktop.org/~agd5f/linux into drm-next

amd-drm-fixes-5.10-2020-10-21:

amdgpu:
- Sienna Cichlid fixes
- MST manager resource leak fix
- GPU reset fix

amdkfd:
- Luxmark fix for Navi1x
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201022040322.4183-1-alexander.deucher@amd.com