Pull KVM fixes from Paolo Bonzini:
 "More bugfixes, including a few remaining "make W=1" issues such as too
  large frame sizes on some configurations.

  On the ARM side, the compiler was messing up shadow stacks between EL1
  and EL2 code, which is easily fixed with __always_inline"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: check descriptor table exits on instruction emulation
  kvm: x86: Limit the number of "kvm: disabled by bios" messages
  KVM: x86: avoid useless copy of cpufreq policy
  KVM: allow disabling -Werror
  KVM: x86: allow compiling as non-module with W=1
  KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
  KVM: Introduce pv check helpers
  KVM: let declaration of kvm_get_running_vcpus match implementation
  KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter
  arm64: Ask the compiler to __always_inline functions used by KVM at HYP
  KVM: arm64: Define our own swab32() to avoid a uapi static inline
  KVM: arm64: Ask the compiler to __always_inline functions used at HYP
  kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()
  KVM: arm/arm64: Fix up includes for trace.h

KVM emulates UMIP on hardware that doesn't support it by setting the
'descriptor table exiting' VM-execution control and performing
instruction emulation. When running nested, this emulation is broken as
KVM refuses to emulate L2 instructions by default.

Correct this regression by allowing the emulation of descriptor table
instructions if L1 hasn't requested 'descriptor table exiting'.

Fixes: 07721fee ("KVM: nVMX: Don't emulate instructions in guest mode")
Reported-by: NJan Kiszka <jan.kiszka@web.de>
Cc: stable@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: NOliver Upton <oupton@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Pull i2c fixes from Wolfram Sang:
 "I2C has three driver bugfixes for you. We agreed on the Mac regression
  to go in via I2C"

* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  macintosh: therm_windtunnel: fix regression when instantiating devices
  i2c: altera: Fix potential integer overflow
  i2c: jz4780: silence log flood on txabrt

Removing attach_adapter from this driver caused a regression for at
least some machines. Those machines had the sensors described in their
DT, too, so they didn't need manual creation of the sensor devices. The
old code worked, though, because manual creation came first. Creation of
DT devices then failed later and caused error logs, but the sensors
worked nonetheless because of the manually created devices.

When removing attach_adaper, manual creation now comes later and loses
the race. The sensor devices were already registered via DT, yet with
another binding, so the driver could not be bound to it.

This fix refactors the code to remove the race and only manually creates
devices if there are no DT nodes present. Also, the DT binding is updated
to match both, the DT and manually created devices. Because we don't
know which device creation will be used at runtime, the code to start
the kthread is moved to do_probe() which will be called by both methods.

Fixes: 3e7bed52 ("macintosh: therm_windtunnel: drop using attach_adapter")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201723Reported-by: NErhard Furtner <erhard_f@mailbox.org>
Tested-by: NErhard Furtner <erhard_f@mailbox.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org # v4.19+

Pull SCSI fixes from James Bottomley:
 "Four small fixes.

  Three are in drivers for fairly obvious bugs. The fourth is a set of
  regressions introduced by the compat_ioctl changes because some of the
  compat updates wrongly replaced .ioctl instead of .compat_ioctl"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: compat_ioctl: cdrom: Replace .ioctl with .compat_ioctl in four appropriate places
  scsi: zfcp: fix wrong data and display format of SFP+ temperature
  scsi: sd_sbc: Fix sd_zbc_report_zones()
  scsi: libfc: free response frame from GPN_ID

Pull PCI fixes from Bjorn Helgaas:

 - Fix build issue on 32-bit ARM with old compilers (Marek Szyprowski)

 - Update MAINTAINERS for recent Cadence driver file move (Lukas
   Bulwahn)

* tag 'pci-v5.6-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  MAINTAINERS: Correct Cadence PCI driver path
  PCI: brcmstb: Fix build on 32bit ARM platforms with older compilers

Pull block fixes from Jens Axboe:

 - Passthrough insertion fix (Ming)

 - Kill off some unused arguments (John)

 - blktrace RCU fix (Jan)

 - Dead fields removal for null_blk (Dongli)

 - NVMe polled IO fix (Bijan)

* tag 'block-5.6-2020-02-28' of git://git.kernel.dk/linux-block:
  nvme-pci: Hold cq_poll_lock while completing CQEs
  blk-mq: Remove some unused function arguments
  null_blk: remove unused fields in 'nullb_cmd'
  blktrace: Protect q->blk_trace with RCU
  blk-mq: insert passthrough request into hctx->dispatch directly

Pull io_uring fixes from Jens Axboe:

 - Fix for a race with IOPOLL used with SQPOLL (Xiaoguang)

 - Only show ->fdinfo if procfs is enabled (Tobias)

 - Fix for a chain with multiple personalities in the SQEs

 - Fix for a missing free of personality idr on exit

 - Removal of the spin-for-work optimization

 - Fix for next work lookup on request completion

 - Fix for non-vec read/write result progation in case of links

 - Fix for a fileset references on switch

 - Fix for a recvmsg/sendmsg 32-bit compatability mode

* tag 'io_uring-5.6-2020-02-28' of git://git.kernel.dk/linux-block:
  io_uring: fix 32-bit compatability with sendmsg/recvmsg
  io_uring: define and set show_fdinfo only if procfs is enabled
  io_uring: drop file set ref put/get on switch
  io_uring: import_single_range() returns 0/-ERROR
  io_uring: pick up link work on submit reference drop
  io-wq: ensure work->task_pid is cleared on init
  io-wq: remove spin-for-work optimization
  io_uring: fix poll_list race for SETUP_IOPOLL|SETUP_SQPOLL
  io_uring: fix personality idr leak
  io_uring: handle multiple personalities in link chains

Pull NVMe fix from Keith.

* 'nvme-5.6-rc4' of git://git.infradead.org/nvme:
  nvme-pci: Hold cq_poll_lock while completing CQEs

Pull ACPI fixes from Rafael Wysocki:
 "Fix a couple of configuration issues in the ACPI watchdog (WDAT)
  driver (Mika Westerberg) and make it possible to disable that driver
  at boot time in case it still does not work as expected (Jean
  Delvare)"

* tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: watchdog: Set default timeout in probe
  ACPI: watchdog: Fix gas->access_width usage
  ACPICA: Introduce ACPI_ACCESS_BYTE_WIDTH() macro
  ACPI: watchdog: Allow disabling WDAT at boot

Pull power management fixes from Rafael Wysocki:
 "Fix a recent cpufreq initialization regression (Rafael Wysocki),
  revert a devfreq commit that made incompatible changes and broke user
  land on some systems (Orson Zhai), drop a stale reference to a
  document that has gone away recently (Jonathan Neuschäfer), and fix a
  typo in a hibernation code comment (Alexandre Belloni)"

* tag 'pm-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: Fix policy initialization for internal governor drivers
  Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"
  PM / hibernate: fix typo "reserverd_size" -> "reserved_size"
  Documentation: power: Drop reference to interface.rst

Pull zonefs fixes from Damien Le Moal:
 "Two fixes in here:

   - Revert the initial decision to silently ignore IOCB_NOWAIT for
     asynchronous direct IOs to sequential zone files. Instead, return
     an error to the user to signal that the feature is not supported
     (from Christoph)

   - A fix to zonefs Kconfig to select FS_IOMAP to avoid build failures
     if no other file system already selected this option (from
     Johannes)"

* tag 'zonefs-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonefs: select FS_IOMAP
  zonefs: fix IOCB_NOWAIT handling

Merge tag 'kvmarm-fixes-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.6, take #1

- Fix compilation on 32bit
- Move  VHE guest entry/exit into the VHE-specific entry code
- Make sure all functions called by the non-VHE HYP code is tagged as __always_inline

In older version of systemd(219), at boot time, udevadm is called with :
	/usr/bin/udevadm trigger --type=devices --action=add"

This program generates an echo "add" in /sys/devices/system/cpu/cpu<x>/uevent,
leading to the "kvm: disabled by bios" message in case of your Bios disabled
the virtualization extensions.

On a modern system running up to 256 CPU threads, this pollutes the Kernel logs.

This patch offers to ratelimit this message to avoid any userspace program triggering
this uevent printing this message too often.

This patch is only a workaround but greatly reduce the pollution without
breaking the current behavior of printing a message if some try to instantiate
KVM on a system that doesn't support it.

Note that recent versions of systemd (>239) do not have trigger this behavior.

This patch will be useful at least for some using older systemd with recent Kernels.
Signed-off-by: NErwan Velu <e.velu@criteo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

* pm-sleep:
  PM / hibernate: fix typo "reserverd_size" -> "reserved_size"
  Documentation: power: Drop reference to interface.rst

* pm-devfreq:
  Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"

struct cpufreq_policy is quite big and it is not a good idea
to allocate one on the stack.  Just use cpufreq_cpu_get and
cpufreq_cpu_put which is even simpler.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Restrict -Werror to well-tested configurations and allow disabling it
via Kconfig.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Compile error with CONFIG_KVM_INTEL=y and W=1:

  CC      arch/x86/kvm/vmx/vmx.o
arch/x86/kvm/vmx/vmx.c:68:32: error: 'vmx_cpu_id' defined but not used [-Werror=unused-const-variable=]
   68 | static const struct x86_cpu_id vmx_cpu_id[] = {
      |                                ^~~~~~~~~~
cc1: all warnings being treated as errors

When building with =y, the MODULE_DEVICE_TABLE macro doesn't generate a
reference to the structure (or any code at all).  This makes W=1 compiles
unhappy.

Wrap both in a #ifdef to avoid the issue.
Signed-off-by: NValdis Kletnieks <valdis.kletnieks@vt.edu>
[Do the same for CONFIG_KVM_AMD. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Nick Desaulniers Reported:

  When building with:
  $ make CC=clang arch/x86/ CFLAGS=-Wframe-larger-than=1000
  The following warning is observed:
  arch/x86/kernel/kvm.c:494:13: warning: stack frame size of 1064 bytes in
  function 'kvm_send_ipi_mask_allbutself' [-Wframe-larger-than=]
  static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int
  vector)
              ^
  Debugging with:
  https://github.com/ClangBuiltLinux/frame-larger-than
  via:
  $ python3 frame_larger_than.py arch/x86/kernel/kvm.o \
    kvm_send_ipi_mask_allbutself
  points to the stack allocated `struct cpumask newmask` in
  `kvm_send_ipi_mask_allbutself`. The size of a `struct cpumask` is
  potentially large, as it's CONFIG_NR_CPUS divided by BITS_PER_LONG for
  the target architecture. CONFIG_NR_CPUS for X86_64 can be as high as
  8192, making a single instance of a `struct cpumask` 1024 B.

This patch fixes it by pre-allocate 1 cpumask variable per cpu and use it for
both pv tlb and pv ipis..
Reported-by: NNick Desaulniers <ndesaulniers@google.com>
Acked-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Introduce some pv check helpers for consistency.
Suggested-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Sparse notices that declaration and implementation do not match:
arch/s390/kvm/../../../virt/kvm/kvm_main.c:4435:17: warning: incorrect type in return expression (different address spaces)
arch/s390/kvm/../../../virt/kvm/kvm_main.c:4435:17:    expected struct kvm_vcpu [noderef] <asn:3> **
arch/s390/kvm/../../../virt/kvm/kvm_main.c:4435:17:    got struct kvm_vcpu *[noderef] <asn:3> *
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Even if APICv is disabled at startup, the backing page and ir_list need
to be initialized in case they are needed later.  The only case in
which this can be skipped is for userspace irqchip, and that must be
done because avic_init_backing_page dereferences vcpu->arch.apic
(which is NULL for userspace irqchip).

Tested-by: rmuncrief@humanavance.com
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=206579Reviewed-by: NMiaohe Lin <linmiaohe@huawei.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Pull drm fixes from Dave Airlie:
 "Just some fixes for this week: amdgpu, radeon and i915.

  The main i915 one is a regression Gen7 (Ivybridge/Haswell), this moves
  them back from trying to use the full-ppgtt support to the aliasing
  version it used to use due to gpu hangs. Otherwise it's pretty quiet.

  amdgpu:
   - Drop DRIVER_USE_AGP
   - Fix memory leak in GPU reset
   - Resume fix for raven

  radeon:
   - Drop DRIVER_USE_AGP

  i915:
   - downgrade gen7 back to aliasing-ppgtt to avoid GPU hangs
   - shrinker fix
   - pmu leak and double free fixes
   - gvt user after free and virtual display reset fixes
   - randconfig build fix"

* tag 'drm-fixes-2020-02-28' of git://anongit.freedesktop.org/drm/drm:
  drm/radeon: Inline drm_get_pci_dev
  drm/amdgpu: Drop DRIVER_USE_AGP
  drm/i915: Avoid recursing onto active vma from the shrinker
  drm/i915/pmu: Avoid using globals for PMU events
  drm/i915/pmu: Avoid using globals for CPU hotplug state
  drm/i915/gtt: Downgrade gen7 (ivb, byt, hsw) back to aliasing-ppgtt
  drm/i915: fix header test with GCOV
  amdgpu/gmc_v9: save/restore sdpif regs during S3
  drm/amdgpu: fix memory leak during TDR test(v2)
  drm/i915/gvt: Fix orphan vgpu dmabuf_objs' lifetime
  drm/i915/gvt: Separate display reset from ALL_ENGINES reset

Merge tag 'drm-intel-fixes-2020-02-27' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

drm/i915 fixes for v5.6-rc4:
- downgrade gen7 back to aliasing-ppgtt to avoid GPU hangs
- shrinker fix
- pmu leak and double free fixes
- gvt user after free and virtual display reset fixes
- randconfig build fix
Signed-off-by: NDave Airlie <airlied@redhat.com>

From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/874kvcsh00.fsf@intel.com

Merge tag 'amd-drm-fixes-5.6-2020-02-26' of git://people.freedesktop.org/~agd5f/linux into drm-fixes

amd-drm-fixes-5.6-2020-02-26:

amdgpu:
- Drop DRIVER_USE_AGP
- Fix memory leak in GPU reset
- Resume fix for raven

radeon:
- Drop DRIVER_USE_AGP
Signed-off-by: NDave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200227034106.3912-1-alexander.deucher@amd.com

Pull networking fixes from David Miller:

 1) Fix leak in nl80211 AP start where we leak the ACL memory, from
    Johannes Berg.

 2) Fix double mutex unlock in mac80211, from Andrei Otcheretianski.

 3) Fix RCU stall in ipset, from Jozsef Kadlecsik.

 4) Fix devlink locking in devlink_dpipe_table_register, from Madhuparna
    Bhowmik.

 5) Fix race causing TX hang in ll_temac, from Esben Haabendal.

 6) Stale eth hdr pointer in br_dev_xmit(), from Nikolay Aleksandrov.

 7) Fix TX hash calculation bounds checking wrt. tc rules, from Amritha
    Nambiar.

 8) Size netlink responses properly in schedule action code to take into
    consideration TCA_ACT_FLAGS. From Jiri Pirko.

 9) Fix firmware paths for mscc PHY driver, from Antoine Tenart.

10) Don't register stmmac notifier multiple times, from Aaro Koskinen.

11) Various rmnet bug fixes, from Taehee Yoo.

12) Fix vsock deadlock in vsock transport release, from Stefano
    Garzarella.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (61 commits)
  net: dsa: mv88e6xxx: Fix masking of egress port
  mlxsw: pci: Wait longer before accessing the device after reset
  sfc: fix timestamp reconstruction at 16-bit rollover points
  vsock: fix potential deadlock in transport->release()
  unix: It's CONFIG_PROC_FS not CONFIG_PROCFS
  net: rmnet: fix packet forwarding in rmnet bridge mode
  net: rmnet: fix bridge mode bugs
  net: rmnet: use upper/lower device infrastructure
  net: rmnet: do not allow to change mux id if mux id is duplicated
  net: rmnet: remove rcu_read_lock in rmnet_force_unassociate_device()
  net: rmnet: fix suspicious RCU usage
  net: rmnet: fix NULL pointer dereference in rmnet_changelink()
  net: rmnet: fix NULL pointer dereference in rmnet_newlink()
  net: phy: marvell: don't interpret PHY status unless resolved
  mlx5: register lag notifier for init network namespace only
  unix: define and set show_fdinfo only if procfs is enabled
  hinic: fix a bug of rss configuration
  hinic: fix a bug of setting hw_ioctxt
  hinic: fix a irq affinity bug
  net/smc: check for valid ib_client_data
  ...

de80f95c ("PCI: cadence: Move all files to per-device cadence
directory") moved files of the PCI cadence drivers, but did not update the
MAINTAINERS entry.

Since then, ./scripts/get_maintainer.pl --self-test complains:

  warning: no file matches F: drivers/pci/controller/pcie-cadence*

Repair the MAINTAINERS entry.

Link: https://lore.kernel.org/r/20200221185402.4703-1-lukas.bulwahn@gmail.comSigned-off-by: NLukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

We must set MSG_CMSG_COMPAT if we're in compatability mode, otherwise
the iovec import for these commands will not do the right thing and fail
the command with -EINVAL.

Found by running the test suite compiled as 32-bit.

Cc: stable@vger.kernel.org
Fixes: aa1fa28f ("io_uring: add support for recvmsg()")
Fixes: 0fa03c62 ("io_uring: add support for sendmsg()")
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add missing ~ to the usage of the mask.
Reported-by: NKevin Benson <Kevin.Benson@zii.aero>
Reported-by: NChris Healy <Chris.Healy@zii.aero>
Fixes: 5c74c54c ("net: dsa: mv88e6xxx: Split monitor port configuration")
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During initialization the driver issues a reset to the device and waits
for 100ms before checking if the firmware is ready. The waiting is
necessary because before that the device is irresponsive and the first
read can result in a completion timeout.

While 100ms is sufficient for Spectrum-1 and Spectrum-2, it is
insufficient for Spectrum-3.

Fix this by increasing the timeout to 200ms.

Fixes: da382875 ("mlxsw: spectrum: Extend to support Spectrum-3 ASIC")
Signed-off-by: NAmit Cohen <amitc@mellanox.com>
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can't just use the top bits of the last sync event as they could be
off-by-one every 65,536 seconds, giving an error in reconstruction of
65,536 seconds.

This patch uses the difference in the bottom 16 bits (mod 2^16) to
calculate an offset that needs to be applied to the last sync event to
get to the current time.
Signed-off-by: NAlexandru-Mihai Maftei <amaftei@solarflare.com>
Acked-by: NMartin Habets <mhabets@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some transports (hyperv, virtio) acquire the sock lock during the
.release() callback.

In the vsock_stream_connect() we call vsock_assign_transport(); if
the socket was previously assigned to another transport, the
vsk->transport->release() is called, but the sock lock is already
held in the vsock_stream_connect(), causing a deadlock reported by
syzbot:

    INFO: task syz-executor280:9768 blocked for more than 143 seconds.
      Not tainted 5.6.0-rc1-syzkaller #0
    "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
    syz-executor280 D27912  9768   9766 0x00000000
    Call Trace:
     context_switch kernel/sched/core.c:3386 [inline]
     __schedule+0x934/0x1f90 kernel/sched/core.c:4082
     schedule+0xdc/0x2b0 kernel/sched/core.c:4156
     __lock_sock+0x165/0x290 net/core/sock.c:2413
     lock_sock_nested+0xfe/0x120 net/core/sock.c:2938
     virtio_transport_release+0xc4/0xd60 net/vmw_vsock/virtio_transport_common.c:832
     vsock_assign_transport+0xf3/0x3b0 net/vmw_vsock/af_vsock.c:454
     vsock_stream_connect+0x2b3/0xc70 net/vmw_vsock/af_vsock.c:1288
     __sys_connect_file+0x161/0x1c0 net/socket.c:1857
     __sys_connect+0x174/0x1b0 net/socket.c:1874
     __do_sys_connect net/socket.c:1885 [inline]
     __se_sys_connect net/socket.c:1882 [inline]
     __x64_sys_connect+0x73/0xb0 net/socket.c:1882
     do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
     entry_SYSCALL_64_after_hwframe+0x49/0xbe

To avoid this issue, this patch remove the lock acquiring in the
.release() callback of hyperv and virtio transports, and it holds
the lock when we call vsk->transport->release() in the vsock core.

Reported-by: syzbot+731710996d79d0d58fbc@syzkaller.appspotmail.com
Fixes: 408624af ("vsock: use local transport when it is loaded")
Signed-off-by: NStefano Garzarella <sgarzare@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes: 3a12500e ("unix: define and set show_fdinfo only if procfs is enabled")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Taehee Yoo says:

====================
net: rmnet: fix several bugs

This patchset is to fix several bugs in RMNET module.

1. The first patch fixes NULL-ptr-deref in rmnet_newlink().
When rmnet interface is being created, it uses IFLA_LINK
without checking NULL.
So, if userspace doesn't set IFLA_LINK, panic will occur.
In this patch, checking NULL pointer code is added.

2. The second patch fixes NULL-ptr-deref in rmnet_changelink().
To get real device in rmnet_changelink(), it uses IFLA_LINK.
But, IFLA_LINK should not be used in rmnet_changelink().

3. The third patch fixes suspicious RCU usage in rmnet_get_port().
rmnet_get_port() uses rcu_dereference_rtnl().
But, rmnet_get_port() is used by datapath.
So, rcu_dereference_bh() should be used instead of rcu_dereference_rtnl().

4. The fourth patch fixes suspicious RCU usage in
rmnet_force_unassociate_device().
RCU critical section should not be scheduled.
But, unregister_netdevice_queue() in the rmnet_force_unassociate_device()
would be scheduled.
So, the RCU warning occurs.
In this patch, the rcu_read_lock() in the rmnet_force_unassociate_device()
is removed because it's unnecessary.

5. The fifth patch fixes duplicate MUX ID case.
RMNET MUX ID is unique.
So, rmnet interface isn't allowed to be created, which have
a duplicate MUX ID.
But, only rmnet_newlink() checks this condition, rmnet_changelink()
doesn't check this.
So, duplicate MUX ID case would happen.

6. The sixth patch fixes upper/lower interface relationship problems.
When IFLA_LINK is used, the upper/lower infrastructure should be used.
Because it checks the maximum depth of upper/lower interfaces and it also
checks circular interface relationship, etc.
In this patch, netdev_upper_dev_link() is used.

7. The seventh patch fixes bridge related problems.
a) ->ndo_del_slave() doesn't work.
b) It couldn't detect circular upper/lower interface relationship.
c) It couldn't prevent stack overflow because of too deep depth
of upper/lower interface
d) It doesn't check the number of lower interfaces.
e) Panics because of several reasons.
These problems are actually the same problem.
So, this patch fixes these problems.

8. The eighth patch fixes packet forwarding issue in bridge mode
Packet forwarding is not working in rmnet bridge mode.
Because when a packet is forwarded, skb_push() for an ethernet header
is needed. But it doesn't call skb_push().
So, the ethernet header will be lost.

Change log:
 - update commit logs.
 - drop two patches in this patchset because of wrong target branch.
   - ("net: rmnet: add missing module alias")
   - ("net: rmnet: print error message when command fails")
 - remove unneessary rcu_read_lock() in the third patch.
 - use rcu_dereference_bh() instead of rcu_dereference in third patch.
 - do not allow to add a bridge device if rmnet interface is already
   bridge mode in the seventh patch.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Packet forwarding is not working in rmnet bridge mode.
Because when a packet is forwarded, skb_push() for an ethernet header
is needed. But it doesn't call skb_push().
So, the ethernet header will be lost.

Test commands:
    modprobe rmnet
    ip netns add nst
    ip netns add nst2
    ip link add veth0 type veth peer name veth1
    ip link add veth2 type veth peer name veth3
    ip link set veth1 netns nst
    ip link set veth3 netns nst2

    ip link add rmnet0 link veth0 type rmnet mux_id 1
    ip link set veth2 master rmnet0
    ip link set veth0 up
    ip link set veth2 up
    ip link set rmnet0 up
    ip a a 192.168.100.1/24 dev rmnet0

    ip netns exec nst ip link set veth1 up
    ip netns exec nst ip a a 192.168.100.2/24 dev veth1
    ip netns exec nst2 ip link set veth3 up
    ip netns exec nst2 ip a a 192.168.100.3/24 dev veth3
    ip netns exec nst2 ping 192.168.100.2

Fixes: 60d58f97 ("net: qualcomm: rmnet: Implement bridge mode")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to attach a bridge interface to the rmnet interface,
"master" operation is used.
(e.g. ip link set dummy1 master rmnet0)
But, in the rmnet_add_bridge(), which is a callback of ->ndo_add_slave()
doesn't register lower interface.
So, ->ndo_del_slave() doesn't work.
There are other problems too.
1. It couldn't detect circular upper/lower interface relationship.
2. It couldn't prevent stack overflow because of too deep depth
of upper/lower interface
3. It doesn't check the number of lower interfaces.
4. Panics because of several reasons.

The root problem of these issues is actually the same.
So, in this patch, these all problems will be fixed.

Test commands:
    modprobe rmnet
    ip link add dummy0 type dummy
    ip link add rmnet0 link dummy0 type rmnet mux_id 1
    ip link add dummy1 master rmnet0 type dummy
    ip link add dummy2 master rmnet0 type dummy
    ip link del rmnet0
    ip link del dummy2
    ip link del dummy1

Splat looks like:
[   41.867595][ T1164] general protection fault, probably for non-canonical address 0xdffffc0000000101I
[   41.869993][ T1164] KASAN: null-ptr-deref in range [0x0000000000000808-0x000000000000080f]
[   41.872950][ T1164] CPU: 0 PID: 1164 Comm: ip Not tainted 5.6.0-rc1+ #447
[   41.873915][ T1164] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   41.875161][ T1164] RIP: 0010:rmnet_unregister_bridge.isra.6+0x71/0xf0 [rmnet]
[   41.876178][ T1164] Code: 48 89 ef 48 89 c6 5b 5d e9 fc fe ff ff e8 f7 f3 ff ff 48 8d b8 08 08 00 00 48 ba 00 7
[   41.878925][ T1164] RSP: 0018:ffff8880c4d0f188 EFLAGS: 00010202
[   41.879774][ T1164] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000101
[   41.887689][ T1164] RDX: dffffc0000000000 RSI: ffffffffb8cf64f0 RDI: 0000000000000808
[   41.888727][ T1164] RBP: ffff8880c40e4000 R08: ffffed101b3c0e3c R09: 0000000000000001
[   41.889749][ T1164] R10: 0000000000000001 R11: ffffed101b3c0e3b R12: 1ffff110189a1e3c
[   41.890783][ T1164] R13: ffff8880c4d0f200 R14: ffffffffb8d56160 R15: ffff8880ccc2c000
[   41.891794][ T1164] FS:  00007f4300edc0c0(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000
[   41.892953][ T1164] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   41.893800][ T1164] CR2: 00007f43003bc8c0 CR3: 00000000ca53e001 CR4: 00000000000606f0
[   41.894824][ T1164] Call Trace:
[   41.895274][ T1164]  ? rcu_is_watching+0x2c/0x80
[   41.895895][ T1164]  rmnet_config_notify_cb+0x1f7/0x590 [rmnet]
[   41.896687][ T1164]  ? rmnet_unregister_bridge.isra.6+0xf0/0xf0 [rmnet]
[   41.897611][ T1164]  ? rmnet_unregister_bridge.isra.6+0xf0/0xf0 [rmnet]
[   41.898508][ T1164]  ? __module_text_address+0x13/0x140
[   41.899162][ T1164]  notifier_call_chain+0x90/0x160
[   41.899814][ T1164]  rollback_registered_many+0x660/0xcf0
[   41.900544][ T1164]  ? netif_set_real_num_tx_queues+0x780/0x780
[   41.901316][ T1164]  ? __lock_acquire+0xdfe/0x3de0
[   41.901958][ T1164]  ? memset+0x1f/0x40
[   41.902468][ T1164]  ? __nla_validate_parse+0x98/0x1ab0
[   41.903166][ T1164]  unregister_netdevice_many.part.133+0x13/0x1b0
[   41.903988][ T1164]  rtnl_delete_link+0xbc/0x100
[ ... ]

Fixes: 60d58f97 ("net: qualcomm: rmnet: Implement bridge mode")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

netdev_upper_dev_link() is useful to manage lower/upper interfaces.
And this function internally validates looping, maximum depth.
All or most virtual interfaces that could have a real interface
(e.g. macsec, macvlan, ipvlan etc.) use lower/upper infrastructure.

Test commands:
    modprobe rmnet
    ip link add dummy0 type dummy
    ip link add rmnet1 link dummy0 type rmnet mux_id 1
    for i in {2..100}
    do
        let A=$i-1
        ip link add rmnet$i link rmnet$A type rmnet mux_id $i
    done
    ip link del dummy0

The purpose of the test commands is to make stack overflow.

Splat looks like:
[   52.411438][ T1395] BUG: KASAN: slab-out-of-bounds in find_busiest_group+0x27e/0x2c00
[   52.413218][ T1395] Write of size 64 at addr ffff8880c774bde0 by task ip/1395
[   52.414841][ T1395]
[   52.430720][ T1395] CPU: 1 PID: 1395 Comm: ip Not tainted 5.6.0-rc1+ #447
[   52.496511][ T1395] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   52.513597][ T1395] Call Trace:
[   52.546516][ T1395]
[   52.558773][ T1395] Allocated by task 3171537984:
[   52.588290][ T1395] BUG: unable to handle page fault for address: ffffffffb999e260
[   52.589311][ T1395] #PF: supervisor read access in kernel mode
[   52.590529][ T1395] #PF: error_code(0x0000) - not-present page
[   52.591374][ T1395] PGD d6818067 P4D d6818067 PUD d6819063 PMD 0
[   52.592288][ T1395] Thread overran stack, or stack corrupted
[   52.604980][ T1395] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[   52.605856][ T1395] CPU: 1 PID: 1395 Comm: ip Not tainted 5.6.0-rc1+ #447
[   52.611764][ T1395] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   52.621520][ T1395] RIP: 0010:stack_depot_fetch+0x10/0x30
[   52.622296][ T1395] Code: ff e9 f9 fe ff ff 48 89 df e8 9c 1d 91 ff e9 ca fe ff ff cc cc cc cc cc cc cc 89 f8 0
[   52.627887][ T1395] RSP: 0018:ffff8880c774bb60 EFLAGS: 00010006
[   52.628735][ T1395] RAX: 00000000001f8880 RBX: ffff8880c774d140 RCX: 0000000000000000
[   52.631773][ T1395] RDX: 000000000000001d RSI: ffff8880c774bb68 RDI: 0000000000003ff0
[   52.649584][ T1395] RBP: ffffea00031dd200 R08: ffffed101b43e403 R09: ffffed101b43e403
[   52.674857][ T1395] R10: 0000000000000001 R11: ffffed101b43e402 R12: ffff8880d900e5c0
[   52.678257][ T1395] R13: ffff8880c774c000 R14: 0000000000000000 R15: dffffc0000000000
[   52.694541][ T1395] FS:  00007fe867f6e0c0(0000) GS:ffff8880da000000(0000) knlGS:0000000000000000
[   52.764039][ T1395] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   52.815008][ T1395] CR2: ffffffffb999e260 CR3: 00000000c26aa005 CR4: 00000000000606e0
[   52.862312][ T1395] Call Trace:
[   52.887133][ T1395] Modules linked in: dummy rmnet veth openvswitch nsh nf_conncount nf_nat nf_conntrack nf_dex
[   52.936749][ T1395] CR2: ffffffffb999e260
[   52.965695][ T1395] ---[ end trace 7e32ca99482dbb31 ]---
[   52.966556][ T1395] RIP: 0010:stack_depot_fetch+0x10/0x30
[   52.971083][ T1395] Code: ff e9 f9 fe ff ff 48 89 df e8 9c 1d 91 ff e9 ca fe ff ff cc cc cc cc cc cc cc 89 f8 0
[   53.003650][ T1395] RSP: 0018:ffff8880c774bb60 EFLAGS: 00010006
[   53.043183][ T1395] RAX: 00000000001f8880 RBX: ffff8880c774d140 RCX: 0000000000000000
[   53.076480][ T1395] RDX: 000000000000001d RSI: ffff8880c774bb68 RDI: 0000000000003ff0
[   53.093858][ T1395] RBP: ffffea00031dd200 R08: ffffed101b43e403 R09: ffffed101b43e403
[   53.112795][ T1395] R10: 0000000000000001 R11: ffffed101b43e402 R12: ffff8880d900e5c0
[   53.139837][ T1395] R13: ffff8880c774c000 R14: 0000000000000000 R15: dffffc0000000000
[   53.141500][ T1395] FS:  00007fe867f6e0c0(0000) GS:ffff8880da000000(0000) knlGS:0000000000000000
[   53.143343][ T1395] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   53.152007][ T1395] CR2: ffffffffb999e260 CR3: 00000000c26aa005 CR4: 00000000000606e0
[   53.156459][ T1395] Kernel panic - not syncing: Fatal exception
[   54.213570][ T1395] Shutting down cpus with NMI
[   54.354112][ T1395] Kernel Offset: 0x33000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0x)
[   54.355687][ T1395] Rebooting in 5 seconds..

Fixes: b37f78f2 ("net: qualcomm: rmnet: Fix crash on real dev unregistration")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Basically, duplicate mux id isn't be allowed.
So, the creation of rmnet will be failed if there is duplicate mux id
is existing.
But, changelink routine doesn't check duplicate mux id.

Test commands:
    modprobe rmnet
    ip link add dummy0 type dummy
    ip link add rmnet0 link dummy0 type rmnet mux_id 1
    ip link add rmnet1 link dummy0 type rmnet mux_id 2
    ip link set rmnet1 type rmnet mux_id 1

Fixes: 23790ef1 ("net: qualcomm: rmnet: Allow to configure flags for existing devices")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The notifier_call() of the slave interface removes rmnet interface with
unregister_netdevice_queue().
But, before calling unregister_netdevice_queue(), it acquires
rcu readlock.
In the RCU critical section, sleeping isn't be allowed.
But, unregister_netdevice_queue() internally calls synchronize_net(),
which would sleep.
So, suspicious RCU usage warning occurs.

Test commands:
    modprobe rmnet
    ip link add dummy0 type dummy
    ip link add dummy1 type dummy
    ip link add rmnet0 link dummy0 type rmnet mux_id 1
    ip link set dummy1 master rmnet0
    ip link del dummy0

Splat looks like:
[   79.639245][ T1195] =============================
[   79.640134][ T1195] WARNING: suspicious RCU usage
[   79.640852][ T1195] 5.6.0-rc1+ #447 Not tainted
[   79.641657][ T1195] -----------------------------
[   79.642472][ T1195] ./include/linux/rcupdate.h:273 Illegal context switch in RCU read-side critical section!
[   79.644043][ T1195]
[   79.644043][ T1195] other info that might help us debug this:
[   79.644043][ T1195]
[   79.645682][ T1195]
[   79.645682][ T1195] rcu_scheduler_active = 2, debug_locks = 1
[   79.646980][ T1195] 2 locks held by ip/1195:
[   79.647629][ T1195]  #0: ffffffffa3cf64f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x457/0x890
[   79.649312][ T1195]  #1: ffffffffa39256c0 (rcu_read_lock){....}, at: rmnet_config_notify_cb+0xf0/0x590 [rmnet]
[   79.651717][ T1195]
[   79.651717][ T1195] stack backtrace:
[   79.652650][ T1195] CPU: 3 PID: 1195 Comm: ip Not tainted 5.6.0-rc1+ #447
[   79.653702][ T1195] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   79.655037][ T1195] Call Trace:
[   79.655560][ T1195]  dump_stack+0x96/0xdb
[   79.656252][ T1195]  ___might_sleep+0x345/0x440
[   79.656994][ T1195]  synchronize_net+0x18/0x30
[   79.661132][ T1195]  netdev_rx_handler_unregister+0x40/0xb0
[   79.666266][ T1195]  rmnet_unregister_real_device+0x42/0xb0 [rmnet]
[   79.667211][ T1195]  rmnet_config_notify_cb+0x1f7/0x590 [rmnet]
[   79.668121][ T1195]  ? rmnet_unregister_bridge.isra.6+0xf0/0xf0 [rmnet]
[   79.669166][ T1195]  ? rmnet_unregister_bridge.isra.6+0xf0/0xf0 [rmnet]
[   79.670286][ T1195]  ? __module_text_address+0x13/0x140
[   79.671139][ T1195]  notifier_call_chain+0x90/0x160
[   79.671973][ T1195]  rollback_registered_many+0x660/0xcf0
[   79.672893][ T1195]  ? netif_set_real_num_tx_queues+0x780/0x780
[   79.675091][ T1195]  ? __lock_acquire+0xdfe/0x3de0
[   79.675825][ T1195]  ? memset+0x1f/0x40
[   79.676367][ T1195]  ? __nla_validate_parse+0x98/0x1ab0
[   79.677290][ T1195]  unregister_netdevice_many.part.133+0x13/0x1b0
[   79.678163][ T1195]  rtnl_delete_link+0xbc/0x100
[ ... ]

Fixes: ceed73a2 ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rmnet_get_port() internally calls rcu_dereference_rtnl(),
which checks RTNL.
But rmnet_get_port() could be called by packet path.
The packet path is not protected by RTNL.
So, the suspicious RCU usage problem occurs.

Test commands:
    modprobe rmnet
    ip netns add nst
    ip link add veth0 type veth peer name veth1
    ip link set veth1 netns nst
    ip link add rmnet0 link veth0 type rmnet mux_id 1
    ip netns exec nst ip link add rmnet1 link veth1 type rmnet mux_id 1
    ip netns exec nst ip link set veth1 up
    ip netns exec nst ip link set rmnet1 up
    ip netns exec nst ip a a 192.168.100.2/24 dev rmnet1
    ip link set veth0 up
    ip link set rmnet0 up
    ip a a 192.168.100.1/24 dev rmnet0
    ping 192.168.100.2

Splat looks like:
[  146.630958][ T1174] WARNING: suspicious RCU usage
[  146.631735][ T1174] 5.6.0-rc1+ #447 Not tainted
[  146.632387][ T1174] -----------------------------
[  146.633151][ T1174] drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c:386 suspicious rcu_dereference_check() !
[  146.634742][ T1174]
[  146.634742][ T1174] other info that might help us debug this:
[  146.634742][ T1174]
[  146.645992][ T1174]
[  146.645992][ T1174] rcu_scheduler_active = 2, debug_locks = 1
[  146.646937][ T1174] 5 locks held by ping/1174:
[  146.647609][ T1174]  #0: ffff8880c31dea70 (sk_lock-AF_INET){+.+.}, at: raw_sendmsg+0xab8/0x2980
[  146.662463][ T1174]  #1: ffffffff93925660 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x243/0x2150
[  146.671696][ T1174]  #2: ffffffff93925660 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x213/0x2940
[  146.673064][ T1174]  #3: ffff8880c19ecd58 (&dev->qdisc_running_key#7){+...}, at: ip_finish_output2+0x714/0x2150
[  146.690358][ T1174]  #4: ffff8880c5796898 (&dev->qdisc_xmit_lock_key#3){+.-.}, at: sch_direct_xmit+0x1e2/0x1020
[  146.699875][ T1174]
[  146.699875][ T1174] stack backtrace:
[  146.701091][ T1174] CPU: 0 PID: 1174 Comm: ping Not tainted 5.6.0-rc1+ #447
[  146.705215][ T1174] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  146.706565][ T1174] Call Trace:
[  146.707102][ T1174]  dump_stack+0x96/0xdb
[  146.708007][ T1174]  rmnet_get_port.part.9+0x76/0x80 [rmnet]
[  146.709233][ T1174]  rmnet_egress_handler+0x107/0x420 [rmnet]
[  146.710492][ T1174]  ? sch_direct_xmit+0x1e2/0x1020
[  146.716193][ T1174]  rmnet_vnd_start_xmit+0x3d/0xa0 [rmnet]
[  146.717012][ T1174]  dev_hard_start_xmit+0x160/0x740
[  146.717854][ T1174]  sch_direct_xmit+0x265/0x1020
[  146.718577][ T1174]  ? register_lock_class+0x14d0/0x14d0
[  146.719429][ T1174]  ? dev_watchdog+0xac0/0xac0
[  146.723738][ T1174]  ? __dev_queue_xmit+0x15fd/0x2940
[  146.724469][ T1174]  ? lock_acquire+0x164/0x3b0
[  146.725172][ T1174]  __dev_queue_xmit+0x20c7/0x2940
[ ... ]

Fixes: ceed73a2 ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>