Commit Graph

479 Commits

Author SHA1 Message Date
Vitaly Kuznetsov
2bc39970e9 x86/kvm/hyper-v: Introduce KVM_GET_SUPPORTED_HV_CPUID
With every new Hyper-V Enlightenment we implement we're forced to add a
KVM_CAP_HYPERV_* capability. While this approach works it is fairly
inconvenient: the majority of the enlightenments we do have corresponding
CPUID feature bit(s) and userspace has to know this anyways to be able to
expose the feature to the guest.

Add KVM_GET_SUPPORTED_HV_CPUID ioctl (backed by KVM_CAP_HYPERV_CPUID, "one
cap to rule them all!") returning all Hyper-V CPUID feature leaves.

Using the existing KVM_GET_SUPPORTED_CPUID doesn't seem to be possible:
Hyper-V CPUID feature leaves intersect with KVM's (e.g. 0x40000000,
0x40000001) and we would probably confuse userspace in case we decide to
return these twice.

KVM_CAP_HYPERV_CPUID's number is interim: we're intended to drop
KVM_CAP_HYPERV_STIMER_DIRECT and use its number instead.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:54 +01:00
Paolo Bonzini
2a31b9db15 kvm: introduce manual dirty log reprotect
There are two problems with KVM_GET_DIRTY_LOG.  First, and less important,
it can take kvm->mmu_lock for an extended period of time.  Second, its user
can actually see many false positives in some cases.  The latter is due
to a benign race like this:

  1. KVM_GET_DIRTY_LOG returns a set of dirty pages and write protects
     them.
  2. The guest modifies the pages, causing them to be marked ditry.
  3. Userspace actually copies the pages.
  4. KVM_GET_DIRTY_LOG returns those pages as dirty again, even though
     they were not written to since (3).

This is especially a problem for large guests, where the time between
(1) and (3) can be substantial.  This patch introduces a new
capability which, when enabled, makes KVM_GET_DIRTY_LOG not
write-protect the pages it returns.  Instead, userspace has to
explicitly clear the dirty log bits just before using the content
of the page.  The new KVM_CLEAR_DIRTY_LOG ioctl can also operate on a
64-page granularity rather than requiring to sync a full memslot;
this way, the mmu_lock is taken for small amounts of time, and
only a small amount of time will pass between write protection
of pages and the sending of their content.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:19 +01:00
Paolo Bonzini
e5d83c74a5 kvm: make KVM_CAP_ENABLE_CAP_VM architecture agnostic
The first such capability to be handled in virt/kvm/ will be manual
dirty page reprotection.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:18 +01:00
Linus Torvalds
0d1e8b8d2b KVM updates for v4.20
ARM:
  - Improved guest IPA space support (32 to 52 bits)
 
  - RAS event delivery for 32bit
 
  - PMU fixes
 
  - Guest entry hardening
 
  - Various cleanups
 
  - Port of dirty_log_test selftest
 
 PPC:
  - Nested HV KVM support for radix guests on POWER9.  The performance is
    much better than with PR KVM.  Migration and arbitrary level of
    nesting is supported.
 
  - Disable nested HV-KVM on early POWER9 chips that need a particular hardware
    bug workaround
 
  - One VM per core mode to prevent potential data leaks
 
  - PCI pass-through optimization
 
  - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base
 
 s390:
  - Initial version of AP crypto virtualization via vfio-mdev
 
  - Improvement for vfio-ap
 
  - Set the host program identifier
 
  - Optimize page table locking
 
 x86:
  - Enable nested virtualization by default
 
  - Implement Hyper-V IPI hypercalls
 
  - Improve #PF and #DB handling
 
  - Allow guests to use Enlightened VMCS
 
  - Add migration selftests for VMCS and Enlightened VMCS
 
  - Allow coalesced PIO accesses
 
  - Add an option to perform nested VMCS host state consistency check
    through hardware
 
  - Automatic tuning of lapic_timer_advance_ns
 
  - Many fixes, minor improvements, and cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQEcBAABCAAGBQJb0FINAAoJEED/6hsPKofoI60IAJRS3vOAQ9Fav8cJsO1oBHcX
 3+NexfnBke1bzrjIR3SUcHKGZbdnVPNZc+Q4JjIbPpPmmOMU5jc9BC1dmd5f4Vzh
 BMnQ0yCvgFv3A3fy/Icx1Z8NJppxosdmqdQLrQrNo8aD3cjnqY2yQixdXrAfzLzw
 XEgKdIFCCz8oVN/C9TT4wwJn6l9OE7BM5bMKGFy5VNXzMu7t64UDOLbbjZxNgi1g
 teYvfVGdt5mH0N7b2GPPWRbJmgnz5ygVVpVNQUEFrdKZoCm6r5u9d19N+RRXAwan
 ZYFj10W2T8pJOUf3tryev4V33X7MRQitfJBo4tP5hZfi9uRX89np5zP1CFE7AtY=
 =yEPW
 -----END PGP SIGNATURE-----

Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "ARM:
   - Improved guest IPA space support (32 to 52 bits)

   - RAS event delivery for 32bit

   - PMU fixes

   - Guest entry hardening

   - Various cleanups

   - Port of dirty_log_test selftest

  PPC:
   - Nested HV KVM support for radix guests on POWER9. The performance
     is much better than with PR KVM. Migration and arbitrary level of
     nesting is supported.

   - Disable nested HV-KVM on early POWER9 chips that need a particular
     hardware bug workaround

   - One VM per core mode to prevent potential data leaks

   - PCI pass-through optimization

   - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base

  s390:
   - Initial version of AP crypto virtualization via vfio-mdev

   - Improvement for vfio-ap

   - Set the host program identifier

   - Optimize page table locking

  x86:
   - Enable nested virtualization by default

   - Implement Hyper-V IPI hypercalls

   - Improve #PF and #DB handling

   - Allow guests to use Enlightened VMCS

   - Add migration selftests for VMCS and Enlightened VMCS

   - Allow coalesced PIO accesses

   - Add an option to perform nested VMCS host state consistency check
     through hardware

   - Automatic tuning of lapic_timer_advance_ns

   - Many fixes, minor improvements, and cleanups"

* tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
  KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned
  Revert "kvm: x86: optimize dr6 restore"
  KVM: PPC: Optimize clearing TCEs for sparse tables
  x86/kvm/nVMX: tweak shadow fields
  selftests/kvm: add missing executables to .gitignore
  KVM: arm64: Safety check PSTATE when entering guest and handle IL
  KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips
  arm/arm64: KVM: Enable 32 bits kvm vcpu events support
  arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension()
  KVM: arm64: Fix caching of host MDCR_EL2 value
  KVM: VMX: enable nested virtualization by default
  KVM/x86: Use 32bit xor to clear registers in svm.c
  kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD
  kvm: vmx: Defer setting of DR6 until #DB delivery
  kvm: x86: Defer setting of CR2 until #PF delivery
  kvm: x86: Add payload operands to kvm_multiple_exception
  kvm: x86: Add exception payload fields to kvm_vcpu_events
  kvm: x86: Add has_payload and payload to kvm_queued_exception
  KVM: Documentation: Fix omission in struct kvm_vcpu_events
  KVM: selftests: add Enlightened VMCS test
  ...
2018-10-25 17:57:35 -07:00
Linus Torvalds
01aa9d518e This is a fairly typical cycle for documentation. There's some welcome
readability improvements for the formatted output, some LICENSES updates
 including the addition of the ISC license, the removal of the unloved and
 unmaintained 00-INDEX files, the deprecated APIs document from Kees, more
 MM docs from Mike Rapoport, and the usual pile of typo fixes and
 corrections.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJbztcuAAoJEI3ONVYwIuV6nTAP/0Be+5dNPGJmSnb/RbkwBuBV
 zAFVUj2sx4lZlRmWRZ0r7AOef2eSw3IvwBix/vnmllYCVahjp+BdRbhXQAijjyeb
 FWWjOH50/J+BaxSthAINiLRLvuoe0D/M08OpmXQfRl5q0S8RufeV3BDtEABx9j2n
 IICPGTl8LpPUgSMA4cw8zPhHdauhZpbmL2mGE9LXZ27SJT4S8lcHMwyPU1n5S+Jd
 ChEz5g9dYr3GNxFp712pkI5GcVL3tP2nfoVwK7EuGf1tvSnEnn2kzac8QgMqorIh
 xB2+Sh4XIUCbHYpGHpxIniD+WI4voNr/E7STQioJK5o2G4HTuxLjktvTezNF8paa
 hgNHWjPQBq0OOCdM/rsffONFF2J/v/r7E3B+kaRg8pE0uZWTFaDMs6MVaL2fL4Ls
 DrFhi90NJI/Fs7uB4sriiviShAhwboiSIRXJi4VlY/5oFJKHFgqes+R7miU+zTX3
 2qv0k4mWZXWDV9w1piPxSCZSdRzaoYSoxEihX+tnYpCyEcYd9ovW/X1Uhl/wCWPl
 Ft+Op6rkHXRXVfZzTLuF6PspZ4Udpw2PUcnA5zj5FRDDBsjSMFR31c19IFbCeiNY
 kbTIcqejJG1WbVrAK4LCcFyVSGxbrr281eth4rE06cYmmsz3kJy1DB6Lhyg/2vI0
 I8K9ZJ99n1RhPJIcburB
 =C0wt
 -----END PGP SIGNATURE-----

Merge tag 'docs-4.20' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This is a fairly typical cycle for documentation. There's some welcome
  readability improvements for the formatted output, some LICENSES
  updates including the addition of the ISC license, the removal of the
  unloved and unmaintained 00-INDEX files, the deprecated APIs document
  from Kees, more MM docs from Mike Rapoport, and the usual pile of typo
  fixes and corrections"

* tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits)
  docs: Fix typos in histogram.rst
  docs: Introduce deprecated APIs list
  kernel-doc: fix declaration type determination
  doc: fix a typo in adding-syscalls.rst
  docs/admin-guide: memory-hotplug: remove table of contents
  doc: printk-formats: Remove bogus kobject references for device nodes
  Documentation: preempt-locking: Use better example
  dm flakey: Document "error_writes" feature
  docs/completion.txt: Fix a couple of punctuation nits
  LICENSES: Add ISC license text
  LICENSES: Add note to CDDL-1.0 license that it should not be used
  docs/core-api: memory-hotplug: add some details about locking internals
  docs/core-api: rename memory-hotplug-notifier to memory-hotplug
  docs: improve readability for people with poorer eyesight
  yama: clarify ptrace_scope=2 in Yama documentation
  docs/vm: split memory hotplug notifier description to Documentation/core-api
  docs: move memory hotplug description into admin-guide/mm
  doc: Fix acronym "FEKEK" in ecryptfs
  docs: fix some broken documentation references
  iommu: Fix passthrough option documentation
  ...
2018-10-24 18:01:11 +01:00
Paolo Bonzini
e42b4a507e KVM/arm updates for 4.20
- Improved guest IPA space support (32 to 52 bits)
 - RAS event delivery for 32bit
 - PMU fixes
 - Guest entry hardening
 - Various cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAlvJ0HIVHG1hcmMuenlu
 Z2llckBhcm0uY29tAAoJECPQ0LrRPXpDnWsP/02W6iIZUlg0SfsNq3bownJv+3VH
 BwEWTfRhWqqzSnsPwUEcOakKI8OIDJ07wIr6XoqPqq2PESS4BQv90qUTxytJXIt4
 gdTxZbNdCSzOc8Zf5URi1WtydekxsEFKgZy9iYWuILJzGW8iFbDZasgG6l8TWupN
 SsoyoGYBVwqR4xRf2f+PLf2n4U0McM8gFuKBFpnp1vCg6gZMBOvvKxQSRk9lUXEL
 C5LERL1CsGVn1Q2GxEB4yAxqrlAMMjy/S2dAf2KpCvMvviK3t05C4vY/+/mT21YE
 wCStX7W5Jfhy3hEsyHCkeulODdomIyro32/hw1qLhMXv4+wRvoiNrMVEoxUPi+by
 L89C6slwxqZOgcF2epSQgf7LBiLw+LnCGtACq2xY7p8yGuy0XW7mK9DlY5RvBHka
 aMmZ6kK/GIZFqRHDHa+ND2cAqS+Xyg2t/j2rvUPL0/xNelI1hpUUyGECTcqAXLr7
 N28+8aoHWcYb03r8YwfgWkEcwT9leAS45NBmHgnkOL4srcyW7anSW4NhZb/+U0mM
 8cLF+2BxfUo733Q5EyM2Q3JdbgaDaeanf6zzy7xAsPEywK4P5/kdqjc0N9se+LUx
 WhU3BRDU4KwV6S7bBS9ZuFK3heuwfuKWaYwwDaxrTlem++8FhoLBNV2vN8VjemD/
 AY5RvHrEhFYndijj
 =vjLz
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-for-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for 4.20

- Improved guest IPA space support (32 to 52 bits)
- RAS event delivery for 32bit
- PMU fixes
- Guest entry hardening
- Various cleanups
2018-10-19 15:24:24 +02:00
Jim Mattson
c4f55198c7 kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD
This is a per-VM capability which can be enabled by userspace so that
the faulting linear address will be included with the information
about a pending #PF in L2, and the "new DR6 bits" will be included
with the information about a pending #DB in L2. With this capability
enabled, the L1 hypervisor can now intercept #PF before CR2 is
modified. Under VMX, the L1 hypervisor can now intercept #DB before
DR6 and DR7 are modified.

When userspace has enabled KVM_CAP_EXCEPTION_PAYLOAD, it should
generally provide an appropriate payload when injecting a #PF or #DB
exception via KVM_SET_VCPU_EVENTS. However, to support restoring old
checkpoints, this payload is not required.

Note that bit 16 of the "new DR6 bits" is set to indicate that a debug
exception (#DB) or a breakpoint exception (#BP) occurred inside an RTM
region while advanced debugging of RTM transactional regions was
enabled. This is the reverse of DR6.RTM, which is cleared in this
scenario.

This capability also enables exception.pending in struct
kvm_vcpu_events, which allows userspace to distinguish between pending
and injected exceptions.

Reported-by: Jim Mattson <jmattson@google.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17 19:07:44 +02:00
Jim Mattson
59073aaf6d kvm: x86: Add exception payload fields to kvm_vcpu_events
The per-VM capability KVM_CAP_EXCEPTION_PAYLOAD (to be introduced in a
later commit) adds the following fields to struct kvm_vcpu_events:
exception_has_payload, exception_payload, and exception.pending.

With this capability set, all of the details of vcpu->arch.exception,
including the payload for a pending exception, are reported to
userspace in response to KVM_GET_VCPU_EVENTS.

With this capability clear, the original ABI is preserved, and the
exception.injected field is set for either pending or injected
exceptions.

When userspace calls KVM_SET_VCPU_EVENTS with
KVM_CAP_EXCEPTION_PAYLOAD clear, exception.injected is no longer
translated to exception.pending. KVM_SET_VCPU_EVENTS can now only
establish a pending exception when KVM_CAP_EXCEPTION_PAYLOAD is set.

Reported-by: Jim Mattson <jmattson@google.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17 19:07:38 +02:00
Jim Mattson
bba9ce58d9 KVM: Documentation: Fix omission in struct kvm_vcpu_events
The header file indicates that there are 36 reserved bytes at the end
of this structure. Adjust the documentation to agree with the header
file.

Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17 00:30:21 +02:00
Peng Hao
0804c849f1 kvm/x86 : add coalesced pio support
Coalesced pio is based on coalesced mmio and can be used for some port
like rtc port, pci-host config port and so on.

Specially in case of rtc as coalesced pio, some versions of windows guest
access rtc frequently because of rtc as system tick. guest access rtc like
this: write register index to 0x70, then write or read data from 0x71.
writing 0x70 port is just as index and do nothing else. So we can use
coalesced pio to handle this scene to reduce VM-EXIT time.

When starting and closing a virtual machine, it will access pci-host config
port frequently. So setting these port as coalesced pio can reduce startup
and shutdown time.

without my patch, get the vm-exit time of accessing rtc 0x70 and piix 0xcf8
using perf tools: (guest OS : windows 7 64bit)
IO Port Access  Samples Samples%  Time%  Min Time  Max Time  Avg time
0x70:POUT        86     30.99%    74.59%   9us      29us    10.75us (+- 3.41%)
0xcf8:POUT     1119     2.60%     2.12%   2.79us    56.83us 3.41us (+- 2.23%)

with my patch
IO Port Access  Samples Samples%  Time%   Min Time  Max Time   Avg time
0x70:POUT       106    32.02%    29.47%    0us      10us     1.57us (+- 7.38%)
0xcf8:POUT      1065    1.67%     0.28%   0.41us    65.44us   0.66us (+- 10.55%)

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17 00:30:11 +02:00
Peng Hao
9943450b7b kvm/x86 : add document for coalesced mmio
Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17 00:30:10 +02:00
Vitaly Kuznetsov
214ff83d44 KVM: x86: hyperv: implement PV IPI send hypercalls
Using hypercall for sending IPIs is faster because this allows to specify
any number of vCPUs (even > 64 with sparse CPU set), the whole procedure
will take only one VMEXIT.

Current Hyper-V TLFS (v5.0b) claims that HvCallSendSyntheticClusterIpi
hypercall can't be 'fast' (passing parameters through registers) but
apparently this is not true, Windows always uses it as 'fast' so we need
to support that.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17 00:29:47 +02:00
Paul Mackerras
901f8c3f6f KVM: PPC: Book3S HV: Add NO_HASH flag to GET_SMMU_INFO ioctl result
This adds a KVM_PPC_NO_HASH flag to the flags field of the
kvm_ppc_smmu_info struct, and arranges for it to be set when
running as a nested hypervisor, as an unambiguous indication
to userspace that HPT guests are not supported.  Reporting the
KVM_CAP_PPC_MMU_HASH_V3 capability as false could be taken as
indicating only that the new HPT features in ISA V3.0 are not
supported, leaving it ambiguous whether pre-V3.0 HPT features
are supported.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-09 16:14:54 +11:00
Paul Mackerras
aa069a9969 KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualization
With this, userspace can enable a KVM-HV guest to run nested guests
under it.

The administrator can control whether any nested guests can be run;
setting the "nested" module parameter to false prevents any guests
becoming nested hypervisors (that is, any attempt to enable the nested
capability on a guest will fail).  Guests which are already nested
hypervisors will continue to be so.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-09 16:14:47 +11:00
Paul Mackerras
9d67121a4f Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the "ppc-kvm" topic branch of the powerpc tree to get a
series of commits that touch both general arch/powerpc code and KVM
code.  These commits will be merged both via the KVM tree and the
powerpc tree.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-09 16:13:20 +11:00
Paul Mackerras
3032341853 KVM: PPC: Book3S HV: Add one-reg interface to virtual PTCR register
This adds a one-reg register identifier which can be used to read and
set the virtual PTCR for the guest.  This register identifies the
address and size of the virtual partition table for the guest, which
contains information about the nested guests under this guest.

Migrating this value is the only extra requirement for migrating a
guest which has nested guests (assuming of course that the destination
host supports nested virtualization in the kvm-hv module).

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Suzuki K Poulose
233a7cb235 kvm: arm64: Allow tuning the physical address size for VM
Allow specifying the physical address size limit for a new
VM via the kvm_type argument for the KVM_CREATE_VM ioctl. This
allows us to finalise the stage2 page table as early as possible
and hence perform the right checks on the memory slots
without complication. The size is encoded as Log2(PA_Size) in
bits[7:0] of the type field. For backward compatibility the
value 0 is reserved and implies 40bits. Also, lift the limit
of the IPA to host limit and allow lower IPA sizes (e.g, 32).

The userspace could check the extension KVM_CAP_ARM_VM_IPA_SIZE
for the availability of this feature. The cap check returns the
maximum limit for the physical address shift supported by the host.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <cdall@kernel.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-10-03 11:45:20 +01:00
Drew Schmitt
6fbbde9a19 KVM: x86: Control guest reads of MSR_PLATFORM_INFO
Add KVM_CAP_MSR_PLATFORM_INFO so that userspace can disable guest access
to reads of MSR_PLATFORM_INFO.

Disabling access to reads of this MSR gives userspace the control to "expose"
this platform-dependent information to guests in a clear way. As it exists
today, guests that read this MSR would get unpopulated information if userspace
hadn't already set it (and prior to this patch series, only the CPUID faulting
information could have been populated). This existing interface could be
confusing if guests don't handle the potential for incorrect/incomplete
information gracefully (e.g. zero reported for base frequency).

Signed-off-by: Drew Schmitt <dasch@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20 00:51:46 +02:00
Janosch Frank
40ebdb8e59 KVM: s390: Make huge pages unavailable in ucontrol VMs
We currently do not notify all gmaps when using gmap_pmdp_xchg(), due
to locking constraints. This makes ucontrol VMs, which is the only VM
type that creates multiple gmaps, incompatible with huge pages. Also
we would need to hold the guest_table_lock of all gmaps that have this
vmaddr maped to synchronize access to the pmd.

ucontrol VMs are rather exotic and creating a new locking concept is
no easy task. Hence we return EINVAL when trying to active
KVM_CAP_S390_HPAGE_1M and report it as being not available when
checking for it.

Fixes: a4499382 ("KVM: s390: Add huge page enablement control")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20180801112508.138159-1-frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2018-09-12 14:46:37 +02:00
Henrik Austad
a7ddcea58a Drop all 00-INDEX files from Documentation/
This is a respin with a wider audience (all that get_maintainer returned)
and I know this spams a *lot* of people. Not sure what would be the correct
way, so my apologies for ruining your inbox.

The 00-INDEX files are supposed to give a summary of all files present
in a directory, but these files are horribly out of date and their
usefulness is brought into question. Often a simple "ls" would reveal
the same information as the filenames are generally quite descriptive as
a short introduction to what the file covers (it should not surprise
anyone what Documentation/sched/sched-design-CFS.txt covers)

A few years back it was mentioned that these files were no longer really
needed, and they have since then grown further out of date, so perhaps
it is time to just throw them out.

A short status yields the following _outdated_ 00-INDEX files, first
counter is files listed in 00-INDEX but missing in the directory, last
is files present but not listed in 00-INDEX.

List of outdated 00-INDEX:
Documentation: (4/10)
Documentation/sysctl: (0/1)
Documentation/timers: (1/0)
Documentation/blockdev: (3/1)
Documentation/w1/slaves: (0/1)
Documentation/locking: (0/1)
Documentation/devicetree: (0/5)
Documentation/power: (1/1)
Documentation/powerpc: (0/5)
Documentation/arm: (1/0)
Documentation/x86: (0/9)
Documentation/x86/x86_64: (1/1)
Documentation/scsi: (4/4)
Documentation/filesystems: (2/9)
Documentation/filesystems/nfs: (0/2)
Documentation/cgroup-v1: (0/2)
Documentation/kbuild: (0/4)
Documentation/spi: (1/0)
Documentation/virtual/kvm: (1/0)
Documentation/scheduler: (0/2)
Documentation/fb: (0/1)
Documentation/block: (0/1)
Documentation/networking: (6/37)
Documentation/vm: (1/3)

Then there are 364 subdirectories in Documentation/ with several files that
are missing 00-INDEX alltogether (and another 120 with a single file and no
00-INDEX).

I don't really have an opinion to whether or not we /should/ have 00-INDEX,
but the above 00-INDEX should either be removed or be kept up to date. If
we should keep the files, I can try to keep them updated, but I rather not
if we just want to delete them anyway.

As a starting point, remove all index-files and references to 00-INDEX and
see where the discussion is going.

Signed-off-by: Henrik Austad <henrik@austad.us>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Just-do-it-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: [Almost everybody else]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-09-09 15:08:58 -06:00
Dongjiu Geng
688e0581db KVM: Documentation: rename the capability of KVM_CAP_ARM_SET_SERROR_ESR
In the documentation description, this capability's name is
KVM_CAP_ARM_SET_SERROR_ESR, but in the header file this
capability's name is KVM_CAP_ARM_INJECT_SERROR_ESR, so change
the documentation description to make it same.

Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reported-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22 14:08:05 +02:00
Paolo Bonzini
631989303b KVM/arm updates for 4.19
- Support for Group0 interrupts in guests
 - Cache management optimizations for ARMv8.4 systems
 - Userspace interface for RAS, allowing error retrival and injection
 - Fault path optimization
 - Emulated physical timer fixes
 - Random cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCAAzFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAltxmb4VHG1hcmMuenlu
 Z2llckBhcm0uY29tAAoJECPQ0LrRPXpD7E0P/0qn1IMtskaC7EglFCm72+NXe1CW
 ZAtxTHzetjf7977dA3bVsg4gEKvVx5b3YuRT76u4hBoSa0rFJ8Q9iSC8wL4u9Idf
 JUQjwVIUxMeGW5fR0VFDkd9SkDYtNGdjQcVl2I8UpV+lnLC/2Vfr4xR5qBad2pAQ
 zjthdpQMjZWClyhPkOv6WjVsW0lNw0xDkZWgCViBY+TdT7Gmw/q8hmvj9TEwbMGT
 7tmQl9MupQ2bLY8WuTiGA6eNiEZld9esJGthI43xGQDJl4Y3FeciIZWcBru20+wu
 GnC3QS3FlmYlp2WuWcKU9lEGXhmoX/7/1WVhZkoMsIvi05c2JCxSxstK7QNfUaAH
 8q2/Wc0fYIGm2owH+b1Mpn0w37GZtgl7Bxxzakg7B7Ko0q/EnO7z6XVup1/abKRU
 NtUKlWIL7NDiHjHO6j0hBb3rGi7B3wo86P7GTPJb12Dg9EBF5DVhekXeGI/ChzE9
 WIV1PxR0seSapzlJ92HHmWLAtcRLtXXesqcctmN4d2URBtsx9DEwo0Upiz//reYE
 TBncQbtniVt2xXEl7sqNEYei75IxC3Dg1AgDL/zVQDl8PW0UvKo8Qb0cW7EnF9Vg
 AcjD6R72dAgbqUMYOP0nriKxzXwa0Jls9aF3zBgcikKMGeyD6Z/Exlq4LexhSeuw
 cWKsrQUYcLGKZPRN
 =b6+A
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for 4.19

- Support for Group0 interrupts in guests
- Cache management optimizations for ARMv8.4 systems
- Userspace interface for RAS, allowing error retrival and injection
- Fault path optimization
- Emulated physical timer fixes
- Random cleanups
2018-08-22 14:07:56 +02:00
Wanpeng Li
4180bf1b65 KVM: X86: Implement "send IPI" hypercall
Using hypercall to send IPIs by one vmexit instead of one by one for
xAPIC/x2APIC physical mode and one vmexit per-cluster for x2APIC cluster
mode. Intel guest can enter x2apic cluster mode when interrupt remmaping
is enabled in qemu, however, latest AMD EPYC still just supports xapic
mode which can get great improvement by Exit-less IPIs. This patchset
lets a guest send multicast IPIs, with at most 128 destinations per
hypercall in 64-bit mode and 64 vCPUs per hypercall in 32-bit mode.

Hardware: Xeon Skylake 2.5GHz, 2 sockets, 40 cores, 80 threads, the VM
is 80 vCPUs, IPI microbenchmark(https://lkml.org/lkml/2017/12/19/141):

x2apic cluster mode, vanilla

 Dry-run:                         0,            2392199 ns
 Self-IPI:                  6907514,           15027589 ns
 Normal IPI:              223910476,          251301666 ns
 Broadcast IPI:                   0,         9282161150 ns
 Broadcast lock:                  0,         8812934104 ns

x2apic cluster mode, pv-ipi

 Dry-run:                         0,            2449341 ns
 Self-IPI:                  6720360,           15028732 ns
 Normal IPI:              228643307,          255708477 ns
 Broadcast IPI:                   0,         7572293590 ns  => 22% performance boost
 Broadcast lock:                  0,         8316124651 ns

x2apic physical mode, vanilla

 Dry-run:                         0,            3135933 ns
 Self-IPI:                  8572670,           17901757 ns
 Normal IPI:              226444334,          255421709 ns
 Broadcast IPI:                   0,        19845070887 ns
 Broadcast lock:                  0,        19827383656 ns

x2apic physical mode, pv-ipi

 Dry-run:                         0,            2446381 ns
 Self-IPI:                  6788217,           15021056 ns
 Normal IPI:              219454441,          249583458 ns
 Broadcast IPI:                   0,         7806540019 ns  => 154% performance boost
 Broadcast lock:                  0,         9143618799 ns

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-06 17:59:20 +02:00
Jim Mattson
8fcc4b5923 kvm: nVMX: Introduce KVM_CAP_NESTED_STATE
For nested virtualization L0 KVM is managing a bit of state for L2 guests,
this state can not be captured through the currently available IOCTLs. In
fact the state captured through all of these IOCTLs is usually a mix of L1
and L2 state. It is also dependent on whether the L2 guest was running at
the moment when the process was interrupted to save its state.

With this capability, there are two new vcpu ioctls: KVM_GET_NESTED_STATE
and KVM_SET_NESTED_STATE. These can be used for saving and restoring a VM
that is in VMX operation.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jim Mattson <jmattson@google.com>
[karahmed@ - rename structs and functions and make them ready for AMD and
             address previous comments.
           - handle nested.smm state.
           - rebase & a bit of refactoring.
           - Merge 7/8 and 8/8 into one patch. ]
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-06 17:58:30 +02:00
Janosch Frank
a449938297 KVM: s390: Add huge page enablement control
General KVM huge page support on s390 has to be enabled via the
kvm.hpage module parameter. Either nested or hpage can be enabled, as
we currently do not support vSIE for huge backed guests. Once the vSIE
support is added we will either drop the parameter or enable it as
default.

For a guest the feature has to be enabled through the new
KVM_CAP_S390_HPAGE_1M capability and the hpage module
parameter. Enabling it means that cmm can't be enabled for the vm and
disables pfmf and storage key interpretation.

This is due to the fact that in some cases, in upcoming patches, we
have to split huge pages in the guest mapping to be able to set more
granular memory protection on 4k pages. These split pages have fake
page tables that are not visible to the Linux memory management which
subsequently will not manage its PGSTEs, while the SIE will. Disabling
these features lets us manage PGSTE data in a consistent matter and
solve that problem.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2018-07-30 23:13:38 +02:00
James Morse
b0960b9569 KVM: arm: Add 32bit get/set events support
arm64's new use of KVMs get_events/set_events API calls isn't just
or RAS, it allows an SError that has been made pending by KVM as
part of its device emulation to be migrated.

Wire this up for 32bit too.

We only need to read/write the HCR_VA bit, and check that no esr has
been provided, as we don't yet support VDFSR.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Dongjiu Geng <gengdongjiu@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-21 16:02:32 +01:00
Dongjiu Geng
be26b3a734 arm64: KVM: export the capability to set guest SError syndrome
For the arm64 RAS Extension, user space can inject a virtual-SError
with specified ESR. So user space needs to know whether KVM support
to inject such SError, this interface adds this query for this capability.

KVM will check whether system support RAS Extension, if supported, KVM
returns true to user space, otherwise returns false.

Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: James Morse <james.morse@arm.com>
[expanded documentation wording]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-21 16:02:31 +01:00
Dongjiu Geng
b7b27facc7 arm/arm64: KVM: Add KVM_GET/SET_VCPU_EVENTS
For the migrating VMs, user space may need to know the exception
state. For example, in the machine A, KVM make an SError pending,
when migrate to B, KVM also needs to pend an SError.

This new IOCTL exports user-invisible states related to SError.
Together with appropriate user space changes, user space can get/set
the SError exception state to do migrate/snapshot/suspend.

Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: James Morse <james.morse@arm.com>
[expanded documentation wording]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-21 16:02:30 +01:00
Christoffer Dall
327432c246 KVM: arm/arm64: vgic: Update documentation of the GIC devices wrt IIDR
Update the documentation to reflect the ordering requirements of
restoring the GICD_IIDR register before any other registers and the
effects this has on restoring the interrupt groups for an emulated GICv2
instance.

Also remove some outdated limitations in the documentation while we're
at it.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-21 16:02:30 +01:00
Vitaly Kuznetsov
2ddc649810 KVM: fix KVM_CAP_HYPERV_TLBFLUSH paragraph number
KVM_CAP_HYPERV_TLBFLUSH collided with KVM_CAP_S390_PSW-BPB, its paragraph
number should now be 8.18.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-06-22 17:30:20 +02:00
Liran Alon
71e9d9aeec KVM: docs: nVMX: Remove known limitations as they do not exist now
We can document other "Known Limitations" but the ones currently
referenced don't hold anymore...

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 19:18:28 +02:00
Liran Alon
7f4693b8bb KVM: docs: mmu: KVM support exposing SLAT to guests
Fix outdated statement that KVM is not able to expose SLAT
(Second-Layer-Address-Translation) to guests.
This was implemented a long time ago...

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 19:18:27 +02:00
Paolo Bonzini
5eec43a1fa KVM/ARM updates for 4.18
- Lazy context-switching of FPSIMD registers on arm64
 - Allow virtual redistributors to be part of two or more MMIO ranges
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCAAzFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAlsRY14VHG1hcmMuenlu
 Z2llckBhcm0uY29tAAoJECPQ0LrRPXpDMGwP/A3FDrzGSjgC65m037/dsQj/Eniv
 NkpueEVO3Z8UN44j0TNdeUzj6vQD376GVDwnW3mFlQ416A4ZwwHkk8cQhbpP2UvQ
 EqKKUgujvLueZeuAwYG/DtrR9VZ6fh7QLD7Mv8DW/0AaNdBN2LyHEkW0qx7cSXqu
 PijTsImj9B8TSykYc0SlJz7Q7Y5QUOYbWrJqqa1cskOdmpN2ATInnA2haXeO7j8v
 lkb+WZ9R6xiJSzMCeLEzFV6tUvTiaSw5lVL64jpJhbkBNWPIVAza0erm9TSlQaTw
 d3uJlAy0W9UkXSSqvbmtXvBFqCyEOzZ0hwi2MF6RoVuFt1yXwLgHGps6OUkho4Kq
 pXWImaRHwxyQGrOY0qm0cxr+6TjYnjn8rIOzmzBOrKKq+aCIQ+Sl+CtNYzczQYeE
 rOFBQFsMlzSRJWyabUjhBGFNfDmZZaVFKnUekEqXXETtLxzLZtx+W9i4tzoA1stv
 y0+4yAjEyOQoRsAAE3GmzpDsu7Eu2sae6+lTo7DX1y+A7Wi94HKmy47sVjrS+evV
 2SLyVZ4mhwMzaQ7ngrjHLD1GXDlBxxk2X+NSmBVe5z4AsuWeoqy81f0rgjyCQNxo
 swEqs0k7mMDo8GQNjawwzhdDuHYm4gTX5iGs/Nxx6K4OoJ0bgv83yb/goArp+LEU
 /QWT4T37A/pEEECe
 =DUmC
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.18

- Lazy context-switching of FPSIMD registers on arm64
- Allow virtual redistributors to be part of two or more MMIO ranges
2018-06-01 19:17:22 +02:00
Liran Alon
75025cc9d1 KVM: docs: mmu: Fix link to NPT presentation from KVM Forum 2008
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-26 15:37:34 +02:00
Jim Mattson
df9cb9cc5b kvm: x86: Amend the KVM_GET_SUPPORTED_CPUID API documentation
Document the subtle nuances that KVM_CAP_X86_DISABLE_EXITS induces in
the KVM_GET_SUPPORTED_CPUID API.

Fixes: 4d5422cea3 ("KVM: X86: Provide a capability to disable MWAIT intercepts")
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-26 15:37:34 +02:00
Vitaly Kuznetsov
c1aea9196e KVM: x86: hyperv: declare KVM_CAP_HYPERV_TLBFLUSH capability
We need a new capability to indicate support for the newly added
HvFlushVirtualAddress{List,Space}{,Ex} hypercalls. Upon seeing this
capability, userspace is supposed to announce PV TLB flush features
by setting the appropriate CPUID bits (if needed).

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-26 15:35:35 +02:00
Eric Auger
d6c77bd19c KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION
We introduce a new KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attribute in
KVM_DEV_ARM_VGIC_GRP_ADDR group. It allows userspace to provide the
base address and size of a redistributor region

Compared to KVM_VGIC_V3_ADDR_TYPE_REDIST, this new attribute allows
to declare several separate redistributor regions.

So the whole redist space does not need to be contiguous anymore.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-05-25 12:29:26 +01:00
Michael S. Tsirkin
633711e828 kvm: rename KVM_HINTS_DEDICATED to KVM_HINTS_REALTIME
KVM_HINTS_DEDICATED seems to be somewhat confusing:

Guest doesn't really care whether it's the only task running on a host
CPU as long as it's not preempted.

And there are more reasons for Guest to be preempted than host CPU
sharing, for example, with memory overcommit it can get preempted on a
memory access, post copy migration can cause preemption, etc.

Let's call it KVM_HINTS_REALTIME which seems to better
match what guests expect.

Also, the flag most be set on all vCPUs - current guests assume this.
Note so in the documentation.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-17 19:12:13 +02:00
Marc Zyngier
85bd0ba1ff arm/arm64: KVM: Add PSCI version selection API
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.

But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.

This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.

Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-20 16:32:23 +01:00
Andrew Jones
21e94acaaa KVM: trivial documentation cleanups
Add missing entries to the index and ensure the entries are in
alphabetical order. Also amd-memory-encryption.rst is an .rst
not a .txt.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-28 22:47:06 +02:00
Wanpeng Li
caa057a2ca KVM: X86: Provide a capability to disable HLT intercepts
If host CPUs are dedicated to a VM, we can avoid VM exits on HLT.
This patch adds the per-VM capability to disable them.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16 22:03:52 +01:00
Wanpeng Li
4d5422cea3 KVM: X86: Provide a capability to disable MWAIT intercepts
Allowing a guest to execute MWAIT without interception enables a guest
to put a (physical) CPU into a power saving state, where it takes
longer to return from than what may be desired by the host.

Don't give a guest that power over a host by default. (Especially,
since nothing prevents a guest from using MWAIT even when it is not
advertised via CPUID.)

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16 22:03:51 +01:00
Paolo Bonzini
4956aa3b8b KVM: s390: fixes and features
- more kvm stat counters
 - virtio gpu plumbing. The 3 non-KVM/s390 patches have Acks from
   Bartlomiej Zolnierkiewicz, Heiko Carstens and Greg Kroah-Hartman
   but all belong together to make virtio-gpu work as a tty. So
   I carried them in the KVM/s390 tree.
 - document some KVM_CAPs
 - cpu-model only facilities
 - cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJaqXZWAAoJEBF7vIC1phx87qIP/0Zr9yC8uhU2nqtNVXf9Ezhl
 x2Qh7Psk52LQEORcVHzbV5o5YIQrZxDraJ6DHLT6L6Qqpnk3SkUbtUAc+V3nHfFu
 iIOGQ8GgAsjY2E6A5xKp0JcuJB9/3S7C+CDYMUuFhKHSLNwQvZmRQjn2CILugxPU
 lHO3WpT3wrlVxiI/27uD3T3M+PNsyrMSeB75NBbnW5oTGB3/TNl2159aNdbuvl6C
 Kn74P5FrzgGhAPcmIZkQHt6e8RLi1UBoMO/LC6+u0WFMH9E7GriiMt0bSxlsWdt8
 7wCmQ5Pvv6oZm/SNDgULWfbF1iRL06pMMzArjpnAGUcMKcdTnmzs0lBSYNmbDSh4
 LTQ/LBFxhqf39Hn+D/QaPAJiL0wWIHo6tsRJ9JGDatWuU7vgyfMYTBJmvvK4cGIw
 70iSeOer6TqwCcDIOcsQpbA58kVJcYP+FDKV8ADAj6cVfTD+s6npVB+JwDtX2KKJ
 d2t4GUsRmEJUvQjRHxYspSyYDVcPO7KDZ5TpVW5GHo1fbim1P1LO/ti6eo9u9c/T
 By+t+m3CAMubd+zVeB5uz64wdt8ZhgYTFdvYN4L2chh3JWs3wf7Lkeot4vJ7HgoE
 VWNHVxbYovPNMrUVYNzU6zSbDkQz9hvG5rK2mwv7jmxYGUmv/mItDiF7gFsiRWXg
 N63FBCebeaVlfEJniWRz
 =vw46
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: fixes and features

- more kvm stat counters
- virtio gpu plumbing. The 3 non-KVM/s390 patches have Acks from
  Bartlomiej Zolnierkiewicz, Heiko Carstens and Greg Kroah-Hartman
  but all belong together to make virtio-gpu work as a tty. So
  I carried them in the KVM/s390 tree.
- document some KVM_CAPs
- cpu-model only facilities
- cleanups
2018-03-16 22:03:18 +01:00
Christian Borntraeger
5c2b4d5b78 KVM: document KVM_CAP_S390_[BPB|PSW|GMAP|COW]
commit 35b3fde620 ("KVM: s390: wire up bpb feature") has no
documentation for KVM_CAP_S390_BPB. While adding this let's also add
other missing capabilities like KVM_CAP_S390_PSW, KVM_CAP_S390_GMAP and
KVM_CAP_S390_COW.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-03-14 19:21:06 +00:00
Wanpeng Li
a4429e53c9 KVM: Introduce paravirtualization hints and KVM_HINTS_DEDICATED
This patch introduces kvm_para_has_hint() to query for hints about
the configuration of the guests.  The first hint KVM_HINTS_DEDICATED,
is set if the guest has dedicated physical CPUs for each vCPU (i.e.
pinning and no over-commitment).  This allows optimizing spinlocks
and tells the guest to avoid PV TLB flush.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:44 +01:00
Ken Hofsass
01643c51bf KVM: x86: KVM_CAP_SYNC_REGS
This commit implements an enhanced x86 version of S390
KVM_CAP_SYNC_REGS functionality. KVM_CAP_SYNC_REGS "allow[s]
userspace to access certain guest registers without having
to call SET/GET_*REGS”. This reduces ioctl overhead which
is particularly important when userspace is making synchronous
guest state modifications (e.g. when emulating and/or intercepting
instructions).

Originally implemented upstream for the S390, the x86 differences
follow:
- userspace can select the register sets to be synchronized with kvm_run
using bit-flags in the kvm_valid_registers and kvm_dirty_registers
fields.
- vcpu_events is available in addition to the regs and sregs register
sets.

Signed-off-by: Ken Hofsass <hofsass@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Removed wrapper around check for reserved kvm_valid_regs. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:43 +01:00
Ken Hofsass
7b7e39522a KVM: x86: add SYNC_REGS_SIZE_BYTES #define.
Replace hardcoded padding size value for struct kvm_sync_regs
with #define SYNC_REGS_SIZE_BYTES.

Also update the value specified in api.txt from outdated hardcoded
value to SYNC_REGS_SIZE_BYTES.

Signed-off-by: Ken Hofsass <hofsass@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:43 +01:00
Roman Kagan
faeb7833ee kvm: x86: hyperv: guest->host event signaling via eventfd
In Hyper-V, the fast guest->host notification mechanism is the
SIGNAL_EVENT hypercall, with a single parameter of the connection ID to
signal.

Currently this hypercall incurs a user exit and requires the userspace
to decode the parameters and trigger the notification of the potentially
different I/O context.

To avoid the costly user exit, process this hypercall and signal the
corresponding eventfd in KVM, similar to ioeventfd.  The association
between the connection id and the eventfd is established via the newly
introduced KVM_HYPERV_EVENTFD ioctl, and maintained in an
(srcu-protected) IDR.

Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[asm/hyperv.h changes approved by KY Srinivasan. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:36 +01:00
Tom Lendacky
801e459a6f KVM: x86: Add a framework for supporting MSR-based features
Provide a new KVM capability that allows bits within MSRs to be recognized
as features.  Two new ioctls are added to the /dev/kvm ioctl routine to
retrieve the list of these MSRs and then retrieve their values. A kvm_x86_ops
callback is used to determine support for the listed MSR-based features.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[Tweaked documentation. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-01 19:00:28 +01:00
Radim Krčmář
fe2a3027e7 KVM: x86: fix backward migration with async_PF
Guests on new hypersiors might set KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT
bit when enabling async_PF, but this bit is reserved on old hypervisors,
which results in a failure upon migration.

To avoid breaking different cases, we are checking for CPUID feature bit
before enabling the feature and nothing else.

Fixes: 52a5c155cf ("KVM: async_pf: Let guest support delivery of async_pf from guest mode")
Cc: <stable@vger.kernel.org>
Reviewed-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-02-24 01:43:48 +01:00