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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt21
-rw-r--r--Documentation/virt/kvm/api.rst20
-rw-r--r--Documentation/virt/kvm/x86/hypercalls.rst6
3 files changed, 43 insertions, 4 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3edc5ce0e2a3..a51ab4656854 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2962,6 +2962,27 @@
(enabled). Disable by KVM if hardware lacks support
for NPT.
+ kvm-amd.ciphertext_hiding_asids=
+ [KVM,AMD] Ciphertext hiding prevents disallowed accesses
+ to SNP private memory from reading ciphertext. Instead,
+ reads will see constant default values (0xff).
+
+ If ciphertext hiding is enabled, the joint SEV-ES and
+ SEV-SNP ASID space is partitioned into separate SEV-ES
+ and SEV-SNP ASID ranges, with the SEV-SNP range being
+ [1..max_snp_asid] and the SEV-ES range being
+ (max_snp_asid..min_sev_asid), where min_sev_asid is
+ enumerated by CPUID.0x.8000_001F[EDX].
+
+ A non-zero value enables SEV-SNP ciphertext hiding and
+ adjusts the ASID ranges for SEV-ES and SEV-SNP guests.
+ KVM caps the number of SEV-SNP ASIDs at the maximum
+ possible value, e.g. specifying -1u will assign all
+ joint SEV-ES and SEV-SNP ASIDs to SEV-SNP. Note,
+ assigning all joint ASIDs to SEV-SNP, i.e. configuring
+ max_snp_asid == min_sev_asid-1, will effectively make
+ SEV-ES unusable.
+
kvm-arm.mode=
[KVM,ARM,EARLY] Select one of KVM/arm64's modes of
operation.
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index c17a87a0a5ac..6ae24c5ca559 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -2908,6 +2908,16 @@ such as set vcpu counter or reset vcpu, and they have the following id bit patte
0x9030 0000 0002 <reg:16>
+x86 MSR registers have the following id bit patterns::
+ 0x2030 0002 <msr number:32>
+
+Following are the KVM-defined registers for x86:
+
+======================= ========= =============================================
+ Encoding Register Description
+======================= ========= =============================================
+ 0x2030 0003 0000 0000 SSP Shadow Stack Pointer
+======================= ========= =============================================
4.69 KVM_GET_ONE_REG
--------------------
@@ -3075,6 +3085,12 @@ This IOCTL replaces the obsolete KVM_GET_PIT.
Sets the state of the in-kernel PIT model. Only valid after KVM_CREATE_PIT2.
See KVM_GET_PIT2 for details on struct kvm_pit_state2.
+.. Tip::
+ ``KVM_SET_PIT2`` strictly adheres to the spec of Intel 8254 PIT. For example,
+ a ``count`` value of 0 in ``struct kvm_pit_channel_state`` is interpreted as
+ 65536, which is the maximum count value. Refer to `Intel 8254 programmable
+ interval timer <https://www.scs.stanford.edu/10wi-cs140/pintos/specs/8254.pdf>`_.
+
This IOCTL replaces the obsolete KVM_SET_PIT.
@@ -3582,7 +3598,7 @@ VCPU matching underlying host.
---------------------
:Capability: basic
-:Architectures: arm64, mips, riscv
+:Architectures: arm64, mips, riscv, x86 (if KVM_CAP_ONE_REG)
:Type: vcpu ioctl
:Parameters: struct kvm_reg_list (in/out)
:Returns: 0 on success; -1 on error
@@ -3625,6 +3641,8 @@ Note that s390 does not support KVM_GET_REG_LIST for historical reasons
- KVM_REG_S390_GBEA
+Note, for x86, all MSRs enumerated by KVM_GET_MSR_INDEX_LIST are supported as
+type KVM_X86_REG_TYPE_MSR, but are NOT enumerated via KVM_GET_REG_LIST.
4.85 KVM_ARM_SET_DEVICE_ADDR (deprecated)
-----------------------------------------
diff --git a/Documentation/virt/kvm/x86/hypercalls.rst b/Documentation/virt/kvm/x86/hypercalls.rst
index 10db7924720f..521ecf9a8a36 100644
--- a/Documentation/virt/kvm/x86/hypercalls.rst
+++ b/Documentation/virt/kvm/x86/hypercalls.rst
@@ -137,7 +137,7 @@ compute the CLOCK_REALTIME for its clock, at the same instant.
Returns KVM_EOPNOTSUPP if the host does not use TSC clocksource,
or if clock type is different than KVM_CLOCK_PAIRING_WALLCLOCK.
-6. KVM_HC_SEND_IPI
+7. KVM_HC_SEND_IPI
------------------
:Architecture: x86
@@ -158,7 +158,7 @@ corresponds to the APIC ID a2+1, and so on.
Returns the number of CPUs to which the IPIs were delivered successfully.
-7. KVM_HC_SCHED_YIELD
+8. KVM_HC_SCHED_YIELD
---------------------
:Architecture: x86
@@ -170,7 +170,7 @@ a0: destination APIC ID
:Usage example: When sending a call-function IPI-many to vCPUs, yield if
any of the IPI target vCPUs was preempted.
-8. KVM_HC_MAP_GPA_RANGE
+9. KVM_HC_MAP_GPA_RANGE
-------------------------
:Architecture: x86
:Status: active