forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář: "ARM: - icache invalidation optimizations, improving VM startup time - support for forwarded level-triggered interrupts, improving performance for timers and passthrough platform devices - a small fix for power-management notifiers, and some cosmetic changes PPC: - add MMIO emulation for vector loads and stores - allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without requiring the complex thread synchronization of older CPU versions - improve the handling of escalation interrupts with the XIVE interrupt controller - support decrement register migration - various cleanups and bugfixes. s390: - Cornelia Huck passed maintainership to Janosch Frank - exitless interrupts for emulated devices - cleanup of cpuflag handling - kvm_stat counter improvements - VSIE improvements - mm cleanup x86: - hypervisor part of SEV - UMIP, RDPID, and MSR_SMI_COUNT emulation - paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit - allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512 features - show vcpu id in its anonymous inode name - many fixes and cleanups - per-VCPU MSR bitmaps (already merged through x86/pti branch) - stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)" * tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits) KVM: PPC: Book3S: Add MMIO emulation for VMX instructions KVM: PPC: Book3S HV: Branch inside feature section KVM: PPC: Book3S HV: Make HPT resizing work on POWER9 KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code KVM: PPC: Book3S PR: Fix broken select due to misspelling KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs() KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled KVM: PPC: Book3S HV: Drop locks before reading guest memory kvm: x86: remove efer_reload entry in kvm_vcpu_stat KVM: x86: AMD Processor Topology Information x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested kvm: embed vcpu id to dentry of vcpu anon inode kvm: Map PFN-type memory regions as writable (if possible) x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n KVM: arm/arm64: Fixup userspace irqchip static key optimization KVM: arm/arm64: Fix userspace_irqchip_in_use counting KVM: arm/arm64: Fix incorrect timer_is_pending logic MAINTAINERS: update KVM/s390 maintainers MAINTAINERS: add Halil as additional vfio-ccw maintainer MAINTAINERS: add David as a reviewer for KVM/s390 ...
- Loading branch information
Showing
123 changed files
with
6,577 additions
and
1,416 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,247 @@ | ||
====================================== | ||
Secure Encrypted Virtualization (SEV) | ||
====================================== | ||
|
||
Overview | ||
======== | ||
|
||
Secure Encrypted Virtualization (SEV) is a feature found on AMD processors. | ||
|
||
SEV is an extension to the AMD-V architecture which supports running | ||
virtual machines (VMs) under the control of a hypervisor. When enabled, | ||
the memory contents of a VM will be transparently encrypted with a key | ||
unique to that VM. | ||
|
||
The hypervisor can determine the SEV support through the CPUID | ||
instruction. The CPUID function 0x8000001f reports information related | ||
to SEV:: | ||
|
||
0x8000001f[eax]: | ||
Bit[1] indicates support for SEV | ||
... | ||
[ecx]: | ||
Bits[31:0] Number of encrypted guests supported simultaneously | ||
|
||
If support for SEV is present, MSR 0xc001_0010 (MSR_K8_SYSCFG) and MSR 0xc001_0015 | ||
(MSR_K7_HWCR) can be used to determine if it can be enabled:: | ||
|
||
0xc001_0010: | ||
Bit[23] 1 = memory encryption can be enabled | ||
0 = memory encryption can not be enabled | ||
|
||
0xc001_0015: | ||
Bit[0] 1 = memory encryption can be enabled | ||
0 = memory encryption can not be enabled | ||
|
||
When SEV support is available, it can be enabled in a specific VM by | ||
setting the SEV bit before executing VMRUN.:: | ||
|
||
VMCB[0x90]: | ||
Bit[1] 1 = SEV is enabled | ||
0 = SEV is disabled | ||
|
||
SEV hardware uses ASIDs to associate a memory encryption key with a VM. | ||
Hence, the ASID for the SEV-enabled guests must be from 1 to a maximum value | ||
defined in the CPUID 0x8000001f[ecx] field. | ||
|
||
SEV Key Management | ||
================== | ||
|
||
The SEV guest key management is handled by a separate processor called the AMD | ||
Secure Processor (AMD-SP). Firmware running inside the AMD-SP provides a secure | ||
key management interface to perform common hypervisor activities such as | ||
encrypting bootstrap code, snapshot, migrating and debugging the guest. For more | ||
information, see the SEV Key Management spec [api-spec]_ | ||
|
||
KVM implements the following commands to support common lifecycle events of SEV | ||
guests, such as launching, running, snapshotting, migrating and decommissioning. | ||
|
||
1. KVM_SEV_INIT | ||
--------------- | ||
|
||
The KVM_SEV_INIT command is used by the hypervisor to initialize the SEV platform | ||
context. In a typical workflow, this command should be the first command issued. | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
2. KVM_SEV_LAUNCH_START | ||
----------------------- | ||
|
||
The KVM_SEV_LAUNCH_START command is used for creating the memory encryption | ||
context. To create the encryption context, user must provide a guest policy, | ||
the owner's public Diffie-Hellman (PDH) key and session information. | ||
|
||
Parameters: struct kvm_sev_launch_start (in/out) | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_launch_start { | ||
__u32 handle; /* if zero then firmware creates a new handle */ | ||
__u32 policy; /* guest's policy */ | ||
|
||
__u64 dh_uaddr; /* userspace address pointing to the guest owner's PDH key */ | ||
__u32 dh_len; | ||
|
||
__u64 session_addr; /* userspace address which points to the guest session information */ | ||
__u32 session_len; | ||
}; | ||
|
||
On success, the 'handle' field contains a new handle and on error, a negative value. | ||
|
||
For more details, see SEV spec Section 6.2. | ||
|
||
3. KVM_SEV_LAUNCH_UPDATE_DATA | ||
----------------------------- | ||
|
||
The KVM_SEV_LAUNCH_UPDATE_DATA is used for encrypting a memory region. It also | ||
calculates a measurement of the memory contents. The measurement is a signature | ||
of the memory contents that can be sent to the guest owner as an attestation | ||
that the memory was encrypted correctly by the firmware. | ||
|
||
Parameters (in): struct kvm_sev_launch_update_data | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_launch_update { | ||
__u64 uaddr; /* userspace address to be encrypted (must be 16-byte aligned) */ | ||
__u32 len; /* length of the data to be encrypted (must be 16-byte aligned) */ | ||
}; | ||
|
||
For more details, see SEV spec Section 6.3. | ||
|
||
4. KVM_SEV_LAUNCH_MEASURE | ||
------------------------- | ||
|
||
The KVM_SEV_LAUNCH_MEASURE command is used to retrieve the measurement of the | ||
data encrypted by the KVM_SEV_LAUNCH_UPDATE_DATA command. The guest owner may | ||
wait to provide the guest with confidential information until it can verify the | ||
measurement. Since the guest owner knows the initial contents of the guest at | ||
boot, the measurement can be verified by comparing it to what the guest owner | ||
expects. | ||
|
||
Parameters (in): struct kvm_sev_launch_measure | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_launch_measure { | ||
__u64 uaddr; /* where to copy the measurement */ | ||
__u32 len; /* length of measurement blob */ | ||
}; | ||
|
||
For more details on the measurement verification flow, see SEV spec Section 6.4. | ||
|
||
5. KVM_SEV_LAUNCH_FINISH | ||
------------------------ | ||
|
||
After completion of the launch flow, the KVM_SEV_LAUNCH_FINISH command can be | ||
issued to make the guest ready for the execution. | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
6. KVM_SEV_GUEST_STATUS | ||
----------------------- | ||
|
||
The KVM_SEV_GUEST_STATUS command is used to retrieve status information about a | ||
SEV-enabled guest. | ||
|
||
Parameters (out): struct kvm_sev_guest_status | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_guest_status { | ||
__u32 handle; /* guest handle */ | ||
__u32 policy; /* guest policy */ | ||
__u8 state; /* guest state (see enum below) */ | ||
}; | ||
|
||
SEV guest state: | ||
|
||
:: | ||
|
||
enum { | ||
SEV_STATE_INVALID = 0; | ||
SEV_STATE_LAUNCHING, /* guest is currently being launched */ | ||
SEV_STATE_SECRET, /* guest is being launched and ready to accept the ciphertext data */ | ||
SEV_STATE_RUNNING, /* guest is fully launched and running */ | ||
SEV_STATE_RECEIVING, /* guest is being migrated in from another SEV machine */ | ||
SEV_STATE_SENDING /* guest is getting migrated out to another SEV machine */ | ||
}; | ||
|
||
7. KVM_SEV_DBG_DECRYPT | ||
---------------------- | ||
|
||
The KVM_SEV_DEBUG_DECRYPT command can be used by the hypervisor to request the | ||
firmware to decrypt the data at the given memory region. | ||
|
||
Parameters (in): struct kvm_sev_dbg | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_dbg { | ||
__u64 src_uaddr; /* userspace address of data to decrypt */ | ||
__u64 dst_uaddr; /* userspace address of destination */ | ||
__u32 len; /* length of memory region to decrypt */ | ||
}; | ||
|
||
The command returns an error if the guest policy does not allow debugging. | ||
|
||
8. KVM_SEV_DBG_ENCRYPT | ||
---------------------- | ||
|
||
The KVM_SEV_DEBUG_ENCRYPT command can be used by the hypervisor to request the | ||
firmware to encrypt the data at the given memory region. | ||
|
||
Parameters (in): struct kvm_sev_dbg | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_dbg { | ||
__u64 src_uaddr; /* userspace address of data to encrypt */ | ||
__u64 dst_uaddr; /* userspace address of destination */ | ||
__u32 len; /* length of memory region to encrypt */ | ||
}; | ||
|
||
The command returns an error if the guest policy does not allow debugging. | ||
|
||
9. KVM_SEV_LAUNCH_SECRET | ||
------------------------ | ||
|
||
The KVM_SEV_LAUNCH_SECRET command can be used by the hypervisor to inject secret | ||
data after the measurement has been validated by the guest owner. | ||
|
||
Parameters (in): struct kvm_sev_launch_secret | ||
|
||
Returns: 0 on success, -negative on error | ||
|
||
:: | ||
|
||
struct kvm_sev_launch_secret { | ||
__u64 hdr_uaddr; /* userspace address containing the packet header */ | ||
__u32 hdr_len; | ||
|
||
__u64 guest_uaddr; /* the guest memory region where the secret should be injected */ | ||
__u32 guest_len; | ||
|
||
__u64 trans_uaddr; /* the hypervisor memory region which contains the secret */ | ||
__u32 trans_len; | ||
}; | ||
|
||
References | ||
========== | ||
|
||
.. [white-paper] http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf | ||
.. [api-spec] http://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf | ||
.. [amd-apm] http://support.amd.com/TechDocs/24593.pdf (section 15.34) | ||
.. [kvm-forum] http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.