delta/linux.git/include/uapi/linux/kvm.h, branch proc-cmdline

x86/headers/UAPI: Move DISABLE_EXITS KVM capability bits to the UAPI

2018-04-27T16:37:17+00:00

Move DISABLE_EXITS KVM capability bits to the UAPI just like the rest of
capabilities.

Cc: Paolo Bonzini 
Cc: Radim Krčmář 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: H. Peter Anvin 
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: KarimAllah Ahmed 
Signed-off-by: Radim Krčmář

KVM: X86: Provide a capability to disable MWAIT intercepts

2018-03-16T21:03:51+00:00

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 
Cc: Radim Krčmář 
Cc: Jan H. Schönherr 
Signed-off-by: Wanpeng Li 
Signed-off-by: Paolo Bonzini

KVM: x86: add SYNC_REGS_SIZE_BYTES #define.

2018-03-06T17:40:43+00:00

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Also update the value specified in api.txt from outdated hardcoded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 
Reviewed-by: David Hildenbrand 
Acked-by: Christian Borntraeger 
Signed-off-by: Radim Krčmář

kvm: x86: hyperv: guest->host event signaling via eventfd

2018-03-06T17:40:36+00:00

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 
Reviewed-by: David Hildenbrand 
[asm/hyperv.h changes approved by KY Srinivasan. - Radim]
Signed-off-by: Radim Krčmář

KVM: x86: Add a framework for supporting MSR-based features

2018-03-01T18:00:28+00:00

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 
Signed-off-by: Paolo Bonzini 
[Tweaked documentation. - Radim]
Signed-off-by: Radim Krčmář

Merge branch 'x86/hyperv' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-02-01T14:04:17+00:00

Topic branch for stable KVM clockource under Hyper-V.

Thanks to Christoffer Dall for resolving the ARM conflict.

KVM: s390: wire up bpb feature

2018-01-20T16:30:47+00:00

The new firmware interfaces for branch prediction behaviour changes
are transparently available for the guest. Nevertheless, there is
new state attached that should be migrated and properly resetted.
Provide a mechanism for handling reset, migration and VSIE.

Signed-off-by: Christian Borntraeger 
Reviewed-by: David Hildenbrand 
Reviewed-by: Cornelia Huck 
[Changed capability number to 152. - Radim]
Signed-off-by: Radim Krčmář

KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds

2018-01-19T04:17:01+00:00

This adds a new ioctl, KVM_PPC_GET_CPU_CHAR, that gives userspace
information about the underlying machine's level of vulnerability
to the recently announced vulnerabilities CVE-2017-5715,
CVE-2017-5753 and CVE-2017-5754, and whether the machine provides
instructions to assist software to work around the vulnerabilities.

The ioctl returns two u64 words describing characteristics of the
CPU and required software behaviour respectively, plus two mask
words which indicate which bits have been filled in by the kernel,
for extensibility.  The bit definitions are the same as for the
new H_GET_CPU_CHARACTERISTICS hypercall.

There is also a new capability, KVM_CAP_PPC_GET_CPU_CHAR, which
indicates whether the new ioctl is available.

Signed-off-by: Paul Mackerras

Merge branch 'sev-v9-p2' of https://github.com/codomania/kvm

2018-01-16T15:35:32+00:00

This part of Secure Encrypted Virtualization (SEV) patch series focuses on KVM
changes required to create and manage SEV guests.

SEV is an extension to the AMD-V architecture which supports running encrypted
virtual machine (VMs) under the control of a hypervisor. Encrypted VMs have their
pages (code and data) secured such that only the guest itself has access to
unencrypted version. Each encrypted VM is associated with a unique encryption key;
if its data is accessed to a different entity using a different key the encrypted
guest's data will be incorrectly decrypted, leading to unintelligible data.
This security model ensures that hypervisor will no longer able to inspect or
alter any guest code or data.

The key management of this feature is handled by a separate processor known as
the AMD Secure Processor (AMD-SP) which is present on AMD SOCs. The SEV Key
Management Specification (see below) provides a set of commands which can be
used by hypervisor to load virtual machine keys through the AMD-SP driver.

The patch series adds a new ioctl in KVM driver (KVM_MEMORY_ENCRYPT_OP). The
ioctl will be used by qemu to issue SEV guest-specific commands defined in Key
Management Specification.

The following links provide additional details:

AMD Memory Encryption white paper:
http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf

AMD64 Architecture Programmer's Manual:
    http://support.amd.com/TechDocs/24593.pdf
    SME is section 7.10
    SEV is section 15.34

SEV Key Management:
http://support.amd.com/TechDocs/55766_SEV-KM API_Specification.pdf

KVM Forum Presentation:
http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf

SEV Guest BIOS support:
  SEV support has been add to EDKII/OVMF BIOS
  https://github.com/tianocore/edk2

Signed-off-by: Paolo Bonzini

KVM: s390: mark irq_state.flags as non-usable

2017-12-06T08:18:43+00:00

Old kernels did not check for zero in the irq_state.flags field and old
QEMUs did not zero the flag/reserved fields when calling
KVM_S390_*_IRQ_STATE.  Let's add comments to prevent future uses of
these fields.

Signed-off-by: Christian Borntraeger 
Reviewed-by: Thomas Huth 
Reviewed-by: Cornelia Huck 
Reviewed-by: David Hildenbrand 
Signed-off-by: Christian Borntraeger