The context will be needed to implement the kvm dirty ring.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201001012044.5151-5-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

kvm_clear_guest_page is not used anymore after "KVM: X86: Don't track dirty
for KVM_SET_[TSS_ADDR|IDENTITY_MAP_ADDR]", except from kvm_clear_guest.
We can just inline it in its sole user.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Originally, we have three code paths that can dirty a page without
vcpu context for X86:

  - init_rmode_identity_map
  - init_rmode_tss
  - kvmgt_rw_gpa

init_rmode_identity_map and init_rmode_tss will be setup on
destination VM no matter what (and the guest cannot even see them), so
it does not make sense to track them at all.

To do this, allow __x86_set_memory_region() to return the userspace
address that just allocated to the caller.  Then in both of the
functions we directly write to the userspace address instead of
calling kvm_write_*() APIs.

Another trivial change is that we don't need to explicitly clear the
identity page table root in init_rmode_identity_map() because no
matter what we'll write to the whole page with 4M huge page entries.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201001012044.5151-4-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM_GET_SUPPORTED_HV_CPUID is now supported as both vCPU and VM ioctl,
test that.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200929150944.1235688-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM_GET_SUPPORTED_HV_CPUID is a vCPU ioctl but its output is now
independent from vCPU and in some cases VMMs may want to use it as a system
ioctl instead. In particular, QEMU doesn CPU feature expansion before any
vCPU gets created so KVM_GET_SUPPORTED_HV_CPUID can't be used.

Convert KVM_GET_SUPPORTED_HV_CPUID to 'dual' system/vCPU ioctl with the
same meaning.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200929150944.1235688-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Don't allow the events to accumulate in the eventfd counter, drain them
as they are handled.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20201027135523.646811-4-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Don't allow the events to accumulate in the eventfd counter, drain them
as they are handled.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20201027135523.646811-3-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>

Where events are consumed in the kernel, for example by KVM's
irqfd_wakeup() and VFIO's virqfd_wakeup(), they currently lack a
mechanism to drain the eventfd's counter.

Since the wait queue is already locked while the wakeup functions are
invoked, all they really need to do is call eventfd_ctx_do_read().

Add a check for the lock, and export it for them.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20201027135523.646811-2-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

As far as I can tell, when we use posted interrupts we silently cut off
the events from userspace, if it's listening on the same eventfd that
feeds the irqfd.

I like that behaviour. Let's do it all the time, even without posted
interrupts. It makes it much easier to handle IRQ remapping invalidation
without having to constantly add/remove the fd from the userspace poll
set. We can just leave userspace polling on it, and the bypass will...
well... bypass it.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20201026175325.585623-2-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This allows an exclusive wait_queue_entry to be added at the head of the
queue, instead of the tail as normal. Thus, it gets to consume events
first without allowing non-exclusive waiters to be woken at all.

The (first) intended use is for KVM IRQFD, which currently has
inconsistent behaviour depending on whether posted interrupts are
available or not. If they are, KVM will bypass the eventfd completely
and deliver interrupts directly to the appropriate vCPU. If not, events
are delivered through the eventfd and userspace will receive them when
polling on the eventfd.

By using add_wait_queue_priority(), KVM will be able to consistently
consume events within the kernel without accidentally exposing them
to userspace when they're supposed to be bypassed. This, in turn, means
that userspace doesn't have to jump through hoops to avoid listening
on the erroneously noisy eventfd and injecting duplicate interrupts.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20201027143944.648769-2-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Background: We have a lightweight HV, it needs INIT-VMExit and
SIPI-VMExit to wake-up APs for guests since it do not monitor
the Local APIC. But currently virtual wait-for-SIPI(WFS) state
is not supported in nVMX, so when running on top of KVM, the L1
HV cannot receive the INIT-VMExit and SIPI-VMExit which cause
the L2 guest cannot wake up the APs.

According to Intel SDM Chapter 25.2 Other Causes of VM Exits,
SIPIs cause VM exits when a logical processor is in
wait-for-SIPI state.

In this patch:
    1. introduce SIPI exit reason,
    2. introduce wait-for-SIPI state for nVMX,
    3. advertise wait-for-SIPI support to guest.

When L1 hypervisor is not monitoring Local APIC, L0 need to emulate
INIT-VMExit and SIPI-VMExit to L1 to emulate INIT-SIPI-SIPI for
L2. L2 LAPIC write would be traped by L0 Hypervisor(KVM), L0 should
emulate the INIT/SIPI vmexit to L1 hypervisor to set proper state
for L2's vcpu state.

Handle procdure:
Source vCPU:
    L2 write LAPIC.ICR(INIT).
    L0 trap LAPIC.ICR write(INIT): inject a latched INIT event to target
       vCPU.
Target vCPU:
    L0 emulate an INIT VMExit to L1 if is guest mode.
    L1 set guest VMCS, guest_activity_state=WAIT_SIPI, vmresume.
    L0 set vcpu.mp_state to INIT_RECEIVED if (vmcs12.guest_activity_state
       == WAIT_SIPI).

Source vCPU:
    L2 write LAPIC.ICR(SIPI).
    L0 trap LAPIC.ICR write(INIT): inject a latched SIPI event to traget
       vCPU.
Target vCPU:
    L0 emulate an SIPI VMExit to L1 if (vcpu.mp_state == INIT_RECEIVED).
    L1 set CS:IP, guest_activity_state=ACTIVE, vmresume.
    L0 resume to L2.
    L2 start-up.
Signed-off-by: Yadong Qi <yadong.qi@intel.com>
Message-Id: <20200922052343.84388-1-yadong.qi@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201106065122.403183-1-yadong.qi@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

vmx_apic_init_signal_blocked is buggy in that it returns true
even in VMX non-root mode.  In non-root mode, however, INITs
are not latched, they just cause a vmexit.  Previously,
KVM was waiting for them to be processed when kvm_apic_accept_events
and in the meanwhile it ate the SIPIs that the processor received.

However, in order to implement the wait-for-SIPI activity state,
KVM will have to process KVM_APIC_SIPI in vmx_check_nested_events,
and it will not be possible anymore to disregard SIPIs in non-root
mode as the code is currently doing.

By calling kvm_x86_ops.nested_ops->check_events, we can force a vmexit
(with the side-effect of latching INITs) before incorrectly injecting
an INIT or SIPI in a guest, and therefore vmx_apic_init_signal_blocked
can do the right thing.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Extend the KVM_SET_SREGS test to verify that all supported CR4 bits, as
enumerated by KVM, can be set before KVM_SET_CPUID2, i.e. without first
defining the vCPU model.  KVM is supposed to skip guest CPUID checks
when host userspace is stuffing guest state.

Check the inverse as well, i.e. that KVM rejects KVM_SET_REGS if CR4
has one or more unsupported bits set.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-7-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Rework the common CR4 and SREGS checks to return a bool instead of an
int, i.e. true/false instead of 0/-EINVAL, and add "is" to the name to
clarify the polarity of the return value (which is effectively inverted
by this change).

No functional changed intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-6-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Split out VMX's checks on CR4.VMXE to a dedicated hook, .is_valid_cr4(),
and invoke the new hook from kvm_valid_cr4().  This fixes an issue where
KVM_SET_SREGS would return success while failing to actually set CR4.

Fixing the issue by explicitly checking kvm_x86_ops.set_cr4()'s return
in __set_sregs() is not a viable option as KVM has already stuffed a
variety of vCPU state.

Note, kvm_valid_cr4() and is_valid_cr4() have different return types and
inverted semantics.  This will be remedied in a future patch.

Fixes: 5e1746d6 ("KVM: nVMX: Allow setting the VMXE bit in CR4")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-5-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Drop svm_set_cr4()'s explicit check CR4.VMXE now that common x86 handles
the check by incorporating VMXE into the CR4 reserved bits, via
kvm_cpu_caps.  SVM obviously does not set X86_FEATURE_VMX.

No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-4-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Drop vmx_set_cr4()'s explicit check on the 'nested' module param now
that common x86 handles the check by incorporating VMXE into the CR4
reserved bits, via kvm_cpu_caps.  X86_FEATURE_VMX is set in kvm_cpu_caps
(by vmx_set_cpu_caps()), if and only if 'nested' is true.

No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-3-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Drop vmx_set_cr4()'s somewhat hidden guest_cpuid_has() check on VMXE now
that common x86 handles the check by incorporating VMXE into the CR4
reserved bits, i.e. in cr4_guest_rsvd_bits.  This fixes a bug where KVM
incorrectly rejects KVM_SET_SREGS with CR4.VMXE=1 if it's executed
before KVM_SET_CPUID{,2}.

Fixes: 5e1746d6 ("KVM: nVMX: Allow setting the VMXE bit in CR4")
Reported-by: Stas Sergeev <stsp@users.sourceforge.net>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-2-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In some cases where shadow paging is in use, the root page will
be either mmu->pae_root or vcpu->arch.mmu->lm_root.  Then it will
not have an associated struct kvm_mmu_page, because it is allocated
with alloc_page instead of kvm_mmu_alloc_page.

Just return false quickly from is_tdp_mmu_root if the TDP MMU is
not in use, which also includes the case where shadow paging is
enabled.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

For AMD SEV guests, update the cr3_lm_rsvd_bits to mask
the memory encryption bit in reserved bits.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <160521948301.32054.5783800787423231162.stgit@bmoger-ubuntu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

SEV guests fail to boot on a system that supports the PCID feature.

While emulating the RSM instruction, KVM reads the guest CR3
and calls kvm_set_cr3(). If the vCPU is in the long mode,
kvm_set_cr3() does a sanity check for the CR3 value. In this case,
it validates whether the value has any reserved bits set. The
reserved bit range is 63:cpuid_maxphysaddr(). When AMD memory
encryption is enabled, the memory encryption bit is set in the CR3
value. The memory encryption bit may fall within the KVM reserved
bit range, causing the KVM emulation failure.

Introduce a new field cr3_lm_rsvd_bits in kvm_vcpu_arch which will
cache the reserved bits in the CR3 value. This will be initialized
to rsvd_bits(cpuid_maxphyaddr(vcpu), 63).

If the architecture has any special bits(like AMD SEV encryption bit)
that needs to be masked from the reserved bits, should be cleared
in vendor specific kvm_x86_ops.vcpu_after_set_cpuid handler.

Fixes: a780a3ea ("KVM: X86: Fix reserved bits check for MOV to CR3")
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <160521947657.32054.3264016688005356563.stgit@bmoger-ubuntu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The instruction emulator ignores clflush instructions, yet fails to
support clflushopt. Treat both similarly.

Fixes: 13e457e0 ("KVM: x86: Emulator does not decode clflush well")
Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Message-Id: <20201103120400.240882-1-david.edmondson@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvmarm-fixes-5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for v5.10, take #3

- Allow userspace to downgrade ID_AA64PFR0_EL1.CSV2
- Inject UNDEF on SCXTNUM_ELx access

Pull fscrypt fix from Eric Biggers:
 "Fix a regression where new files weren't using inline encryption when
  they should be"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  fscrypt: fix inline encryption not used on new files

Pull gfs2 fixes from Andreas Gruenbacher:
 "Fix jdata data corruption and glock reference leak"

* tag 'gfs2-v5.10-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix case in which ail writes are done to jdata holes
  Revert "gfs2: Ignore journal log writes for jdata holes"
  gfs2: fix possible reference leak in gfs2_check_blk_type

Pull networking fixes from Jakub Kicinski:
 "Current release - regressions:

   - arm64: dts: fsl-ls1028a-kontron-sl28: specify in-band mode for
     ENETC

  Current release - bugs in new features:

   - mptcp: provide rmem[0] limit offset to fix oops

  Previous release - regressions:

   - IPv6: Set SIT tunnel hard_header_len to zero to fix path MTU
     calculations

   - lan743x: correctly handle chips with internal PHY

   - bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE

   - mlx5e: Fix VXLAN port table synchronization after function reload

  Previous release - always broken:

   - bpf: Zero-fill re-used per-cpu map element

   - fix out-of-order UDP packets when forwarding with UDP GSO fraglists
     turned on:
       - fix UDP header access on Fast/frag0 UDP GRO
       - fix IP header access and skb lookup on Fast/frag0 UDP GRO

   - ethtool: netlink: add missing netdev_features_change() call

   - net: Update window_clamp if SOCK_RCVBUF is set

   - igc: Fix returning wrong statistics

   - ch_ktls: fix multiple leaks and corner cases in Chelsio TLS offload

   - tunnels: Fix off-by-one in lower MTU bounds for ICMP/ICMPv6 replies

   - r8169: disable hw csum for short packets on all chip versions

   - vrf: Fix fast path output packet handling with async Netfilter
     rules"

* tag 'net-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (65 commits)
  lan743x: fix use of uninitialized variable
  net: udp: fix IP header access and skb lookup on Fast/frag0 UDP GRO
  net: udp: fix UDP header access on Fast/frag0 UDP GRO
  devlink: Avoid overwriting port attributes of registered port
  vrf: Fix fast path output packet handling with async Netfilter rules
  cosa: Add missing kfree in error path of cosa_write
  net: switch to the kernel.org patchwork instance
  ch_ktls: stop the txq if reaches threshold
  ch_ktls: tcb update fails sometimes
  ch_ktls/cxgb4: handle partial tag alone SKBs
  ch_ktls: don't free skb before sending FIN
  ch_ktls: packet handling prior to start marker
  ch_ktls: Correction in middle record handling
  ch_ktls: missing handling of header alone
  ch_ktls: Correction in trimmed_len calculation
  cxgb4/ch_ktls: creating skbs causes panic
  ch_ktls: Update cheksum information
  ch_ktls: Correction in finding correct length
  cxgb4/ch_ktls: decrypted bit is not enough
  net/x25: Fix null-ptr-deref in x25_connect
  ...

Pull NFS client bugfixes from Anna Schumaker:
 "Stable fixes:
  - Fix failure to unregister shrinker

  Other fixes:
  - Fix unnecessary locking to clear up some contention
  - Fix listxattr receive buffer size
  - Fix default mount options for nfsroot"

* tag 'nfs-for-5.10-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Remove unnecessary inode lock in nfs_fsync_dir()
  NFS: Remove unnecessary inode locking in nfs_llseek_dir()
  NFS: Fix listxattr receive buffer size
  NFSv4.2: fix failure to unregister shrinker
  nfsroot: Default mount option should ask for built-in NFS version

As the kernel never sets HCR_EL2.EnSCXT, accesses to SCXTNUM_ELx
will trap to EL2. Let's handle that as gracefully as possible
by injecting an UNDEF exception into the guest. This is consistent
with the guest's view of ID_AA64PFR0_EL1.CSV2 being at most 1.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201110141308.451654-4-maz@kernel.org

A large number of system register trap handlers only inject an
UNDEF exeption, and yet each class of sysreg seems to provide its
own, identical function.

Let's unify them all, saving us introducing yet another one later.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201110141308.451654-3-maz@kernel.org

We now expose ID_AA64PFR0_EL1.CSV2=1 to guests running on hosts
that are immune to Spectre-v2, but that don't have this field set,
most likely because they predate the specification.

However, this prevents the migration of guests that have started on
a host the doesn't fake this CSV2 setting to one that does, as KVM
rejects the write to ID_AA64PFR0_EL2 on the grounds that it isn't
what is already there.

In order to fix this, allow userspace to set this field as long as
this doesn't result in a promising more than what is already there
(setting CSV2 to 0 is acceptable, but setting it to 1 when it is
already set to 0 isn't).

Fixes: e1026237 ("KVM: arm64: Set CSV2 for guests on hardware unaffected by Spectre-v2")
Reported-by: Peng Liang <liangpeng10@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201110141308.451654-2-maz@kernel.org

Linux 5.10-rc1
Signed-off-by: Marc Zyngier <maz@kernel.org>

Pull ACPI fixes from Rafael Wysocki:
 "These are mostly docmentation fixes and janitorial changes plus some
  new device IDs and a new quirk.

  Specifics:

   - Fix documentation regarding GPIO properties (Andy Shevchenko)

   - Fix spelling mistakes in ACPI documentation (Flavio Suligoi)

   - Fix white space inconsistencies in ACPI code (Maximilian Luz)

   - Fix string formatting in the ACPI Generic Event Device (GED) driver
     (Nick Desaulniers)

   - Add Intel Alder Lake device IDs to the ACPI drivers used by the
     Dynamic Platform and Thermal Framework (Srinivas Pandruvada)

   - Add lid-related DMI quirk for Medion Akoya E2228T to the ACPI
     button driver (Hans de Goede)"

* tag 'acpi-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: DPTF: Support Alder Lake
  Documentation: ACPI: fix spelling mistakes
  ACPI: button: Add DMI quirk for Medion Akoya E2228T
  ACPI: GED: fix -Wformat
  ACPI: Fix whitespace inconsistencies
  ACPI: scan: Fix acpi_dma_configure_id() kerneldoc name
  Documentation: firmware-guide: gpio-properties: Clarify initial output state
  Documentation: firmware-guide: gpio-properties: active_low only for GpioIo()
  Documentation: firmware-guide: gpio-properties: Fix factual mistakes

Pull power management fixes from Rafael Wysocki:
 "Make the intel_pstate driver behave as expected when it operates in
  the passive mode with HWP enabled and the 'powersave' governor on top
  of it"

* tag 'pm-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: intel_pstate: Take CPUFREQ_GOV_STRICT_TARGET into account
  cpufreq: Add strict_target to struct cpufreq_policy
  cpufreq: Introduce CPUFREQ_GOV_STRICT_TARGET
  cpufreq: Introduce governor flags

When no devicetree is present, the driver will use an
uninitialized variable.

Fix by initializing this variable.

Fixes: 902a66e0 ("lan743x: correctly handle chips with internal PHY")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Link: https://lore.kernel.org/r/20201112152513.1941-1-TheSven73@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Alexander Lobakin says:

====================
net: udp: fix Fast/frag0 UDP GRO

While testing UDP GSO fraglists forwarding through driver that uses
Fast GRO (via napi_gro_frags()), I was observing lots of out-of-order
iperf packets:

[ ID] Interval           Transfer     Bitrate         Jitter
[SUM]  0.0-40.0 sec  12106 datagrams received out-of-order

Simple switch to napi_gro_receive() or any other method without frag0
shortcut completely resolved them.

I've found two incorrect header accesses in GRO receive callback(s):
 - udp_hdr() (instead of udp_gro_udphdr()) that always points to junk
   in "fast" mode and could probably do this in "regular".
   This was the actual bug that caused all out-of-order delivers;
 - udp{4,6}_lib_lookup_skb() -> ip{,v6}_hdr() (instead of
   skb_gro_network_header()) that potentionally might return odd
   pointers in both modes.

Each patch addresses one of these two issues.

This doesn't cover a support for nested tunnels as it's out of the
subject and requires more invasive changes. It will be handled
separately in net-next series.

Credits:
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>

Since v4 [0]:
 - split the fix into two logical ones (Willem);
 - replace ternaries with plain ifs to beautify the code (Jakub);
 - drop p->data part to reintroduce it later in abovementioned set.

Since v3 [1]:
 - restore the original {,__}udp{4,6}_lib_lookup_skb() and use
   private versions of them inside GRO code (Willem).

Since v2 [2]:
 - dropped redundant check introduced in v2 as it's performed right
   before (thanks to Eric);
 - udp_hdr() switched to data + off for skbs from list (also Eric);
 - fixed possible malfunction of {,__}udp{4,6}_lib_lookup_skb() with
   Fast/frag0 due to ip{,v6}_hdr() usage (Willem).

Since v1 [3]:
 - added a NULL pointer check for "uh" as suggested by Willem.

[0] https://lore.kernel.org/netdev/Ha2hou5eJPcblo4abjAqxZRzIl1RaLs2Hy0oOAgFs@cp4-web-036.plabs.ch
[1] https://lore.kernel.org/netdev/MgZce9htmEtCtHg7pmWxXXfdhmQ6AHrnltXC41zOoo@cp7-web-042.plabs.ch
[2] https://lore.kernel.org/netdev/0eaG8xtbtKY1dEKCTKUBubGiC9QawGgB3tVZtNqVdY@cp4-web-030.plabs.ch
[3] https://lore.kernel.org/netdev/YazU6GEzBdpyZMDMwJirxDX7B4sualpDG68ADZYvJI@cp4-web-034.plabs.ch
====================

Link: https://lore.kernel.org/r/hjGOh0iCOYyo1FPiZh6TMXcx3YCgNs1T1eGKLrDz8@cp4-web-037.plabs.chSigned-off-by: Jakub Kicinski <kuba@kernel.org>

udp{4,6}_lib_lookup_skb() use ip{,v6}_hdr() to get IP header of the
packet. While it's probably OK for non-frag0 paths, this helpers
will also point to junk on Fast/frag0 GRO when all headers are
located in frags. As a result, sk/skb lookup may fail or give wrong
results. To support both GRO modes, skb_gro_network_header() might
be used. To not modify original functions, add private versions of
udp{4,6}_lib_lookup_skb() only to perform correct sk lookups on GRO.

Present since the introduction of "application-level" UDP GRO
in 4.7-rc1.

Misc: replace totally unneeded ternaries with plain ifs.

Fixes: a6024562 ("udp: Add GRO functions to UDP socket")
Suggested-by: Willem de Bruijn <willemb@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

UDP GRO uses udp_hdr(skb) in its .gro_receive() callback. While it's
probably OK for non-frag0 paths (when all headers or even the entire
frame are already in skb head), this inline points to junk when
using Fast GRO (napi_gro_frags() or napi_gro_receive() with only
Ethernet header in skb head and all the rest in the frags) and breaks
GRO packet compilation and the packet flow itself.
To support both modes, skb_gro_header_fast() + skb_gro_header_slow()
are typically used. UDP even has an inline helper that makes use of
them, udp_gro_udphdr(). Use that instead of troublemaking udp_hdr()
to get rid of the out-of-order delivers.

Present since the introduction of plain UDP GRO in 5.0-rc1.

Fixes: e20cf8d3 ("udp: implement GRO for plain UDP sockets.")
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Patch b2a846db ("gfs2: Ignore journal log writes for jdata holes")
tried (unsuccessfully) to fix a case in which writes were done to jdata
blocks, the blocks are sent to the ail list, then a punch_hole or truncate
operation caused the blocks to be freed. In other words, the ail items
are for jdata holes. Before b2a846db, the jdata hole caused function
gfs2_block_map to return -EIO, which was eventually interpreted as an
IO error to the journal, and then withdraw.

This patch changes function gfs2_get_block_noalloc, which is only used
for jdata writes, so it returns -ENODATA rather than -EIO, and when
-ENODATA is returned to gfs2_ail1_start_one, the error is ignored.
We can safely ignore it because gfs2_ail1_start_one is only called
when the jdata pages have already been written and truncated, so the
ail1 content no longer applies.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

This reverts commit b2a846db.

That commit changed the behavior of function gfs2_block_map to return
-ENODATA in cases where a hole (IOMAP_HOLE) is encountered and create is
false.  While that fixed the intended problem for jdata, it also broke
other callers of gfs2_block_map such as some jdata block reads.  Before
the patch, an encountered hole would be skipped and the buffer seen as
unmapped by the caller.  The patch changed the behavior to return
-ENODATA, which is interpreted as an error by the caller.

The -ENODATA return code should be restricted to the specific case where
jdata holes are encountered during ail1 writes.  That will be done in a
later patch.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Tony Nguyen says:

====================
Intel Wired LAN Driver Updates 2020-11-10

This series contains updates to i40e and igc drivers and the MAINTAINERS
file.

Slawomir fixes updating VF MAC addresses to fix various issues related
to reporting and setting of these addresses for i40e.

Dan Carpenter fixes a possible used before being initialized issue for
i40e.

Vinicius fixes reporting of netdev stats for igc.

Tony updates repositories for Intel Ethernet Drivers.

* '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue:
  MAINTAINERS: Update repositories for Intel Ethernet Drivers
  igc: Fix returning wrong statistics
  i40e, xsk: uninitialized variable in i40e_clean_rx_irq_zc()
  i40e: Fix MAC address setting for a VF via Host/VM
====================

Link: https://lore.kernel.org/r/20201111001955.533210-1-anthony.l.nguyen@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>