Allocate a page during vCPU creation to be used as the encrypted VM save
area (VMSA) for the SEV-ES guest. Provide a flag in the kvm_vcpu_arch
structure that indicates whether the guest state is protected.

When freeing a VMSA page that has been encrypted, the cache contents must
be flushed using the MSR_AMD64_VM_PAGE_FLUSH before freeing the page.

[ i386 build warnings ]
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Message-Id: <fde272b17eec804f3b9db18c131262fe074015c5.1607620209.git.thomas.lendacky@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add support to KVM for determining if a system is capable of supporting
SEV-ES as well as determining if a guest is an SEV-ES guest.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Message-Id: <e66792323982c822350e40c7a1cf67ea2978a70b.1607620209.git.thomas.lendacky@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

KVM does not have separate ASIDs for L1 and L2; either the nested
hypervisor and nested guests share a single ASID, or on older processor
the ASID is used only to implement TLB flushing.

Either way, ASIDs are handled at the VM level.  In preparation
for having different VMCBs passed to VMLOAD/VMRUN/VMSAVE for L1 and
L2, store the current ASID to struct vcpu_svm and only move it to
the VMCB in svm_vcpu_run.  This way, TLB flushes can be applied
no matter which VMCB will be active during the next svm_vcpu_run.
Signed-off-by: NCathy Avery <cavery@redhat.com>
Message-Id: <20201011184818.3609-2-cavery@redhat.com>
Signed-off-by: NPaolo 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: NSean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20201007014417.29276-5-sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This way we don't waste memory on VMs which don't use nesting
virtualization even when the host enabled it for them.
Signed-off-by: NMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20201001112954.6258-5-mlevitsk@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This will be used to signal an error to the userspace, in case
the vendor code failed during handling of this msr. (e.g -ENOMEM)
Signed-off-by: NMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20201001112954.6258-4-mlevitsk@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We will introduce the concept of MSRs that may not be handled in kernel
space soon. Some MSRs are directly passed through to the guest, effectively
making them handled by KVM from user space's point of view.

This patch introduces all logic required to ensure that MSRs that
user space wants trapped are not marked as direct access for guests.
Signed-off-by: NAlexander Graf <graf@amazon.com>
Message-Id: <20200925143422.21718-6-graf@amazon.com>
[Make terminology a bit more similar to VMX. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Commit 761e4169 created a wrong mask for the
CR3 MBZ bits. According to APM vol 2, only the upper 12 bits are MBZ.

Fixes: 761e4169 ("KVM: nSVM: Check that MBZ bits in CR3 and CR4 are not set on vmrun of nested guests", 2020-07-08)
Signed-off-by: NKrish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <20200829004824.4577-2-krish.sadhukhan@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Remove set_cr_intercept, clr_cr_intercept and is_cr_intercept. Instead
call generic svm_set_intercept, svm_clr_intercept an dsvm_is_intercep
tfor all cr intercepts.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985253016.11252.16945893859439811480.stgit@bmoger-ubuntu>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Convert all the intercepts to one array of 32 bit vectors in
vmcb_control_area. This makes it easy for future intercept vector
additions. Also update trace functions.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985250813.11252.5736581193881040525.stgit@bmoger-ubuntu>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Modify intercept_exceptions to generic intercepts in vmcb_control_area. Use
the generic vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept to
set/clear/test the intercept_exceptions bits.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985250037.11252.1361972528657052410.stgit@bmoger-ubuntu>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Modify intercept_dr to generic intercepts in vmcb_control_area. Use
the generic vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept
to set/clear/test the intercept_dr bits.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985249255.11252.10000868032136333355.stgit@bmoger-ubuntu>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Change intercept_cr to generic intercepts in vmcb_control_area.
Use the new vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept
where applicable.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985248506.11252.9081085950784508671.stgit@bmoger-ubuntu>
[Change constant names. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This is in preparation for the future intercept vector additions.

Add new functions vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept
using kernel APIs __set_bit, __clear_bit and test_bit espectively.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985247876.11252.16039238014239824460.stgit@bmoger-ubuntu>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

host_intercept_exceptions is not used anywhere. Clean it up.
Signed-off-by: NBabu Moger <babu.moger@amd.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Message-Id: <159985252277.11252.8819848322175521354.stgit@bmoger-ubuntu>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This is to be more consistient with VMX, and to support
upcoming addition of vmcb02

Hopefully no functional changes.
Signed-off-by: NMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200827171145.374620-3-mlevitsk@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Some operations in enter_svm_guest_mode() may fail, e.g. currently
we suppress kvm_set_cr3() return value. Prepare the code to proparate
errors.

No functional change intended.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200710141157.1640173-5-vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

According to section "Canonicalization and Consistency Checks" in APM vol. 2
the following guest state is illegal:

    "Any MBZ bit of CR3 is set."
    "Any MBZ bit of CR4 is set."
Suggeted-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKrish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <1594168797-29444-3-git-send-email-krish.sadhukhan@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Match the naming with other nested svm functions.

No functional changes.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Message-Id: <20200625080325.28439-5-joro@8bytes.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Make clear the symbols belong to the SVM code when they are built-in.

No functional changes.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Message-Id: <20200625080325.28439-4-joro@8bytes.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Make it more clear what data structure these functions operate on.

No functional changes.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Message-Id: <20200625080325.28439-3-joro@8bytes.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Renaming is only needed in the svm.h header file.

No functional changes.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Message-Id: <20200625080325.28439-2-joro@8bytes.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Both the vcpu_vmx structure and the vcpu_svm structure have a
'last_cpu' field. Move the common field into the kvm_vcpu_arch
structure. For clarity, rename it to 'last_vmentry_cpu.'
Suggested-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NJim Mattson <jmattson@google.com>
Reviewed-by: NOliver Upton <oupton@google.com>
Reviewed-by: NPeter Shier <pshier@google.com>
Message-Id: <20200603235623.245638-6-jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

According to the AMD manual, the effect of turning off EFER.SVME while a
guest is running is undefined.  We make it leave guest mode immediately,
similar to the effect of clearing the VMX bit in MSR_IA32_FEAT_CTL.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Now that the int_ctl field is stored in svm->nested.ctl.int_ctl, we can
use it instead of vcpu->arch.hflags to check whether L2 is running
in V_INTR_MASKING mode.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Extract the code that is needed to implement CLGI and STGI,
so that we can run it from VMRUN and vmexit (and in the future,
KVM_SET_NESTED_STATE).  Skip the request for KVM_REQ_EVENT unless needed,
subsuming the evaluate_pending_interrupts optimization that is found
in enter_svm_guest_mode.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The control state changes on every L2->L0 vmexit, and we will have to
serialize it in the nested state.  So keep it up to date in svm->nested.ctl
and just copy them back to the nested VMCB in nested_svm_vmexit.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In preparation for nested SVM save/restore, store all data that matters
from the VMCB control area into svm->nested.  It will then become part
of the nested SVM state that is saved by KVM_SET_NESTED_STATE and
restored by KVM_GET_NESTED_STATE, just like the cached vmcs12 for nVMX.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Unmapping the nested VMCB in enter_svm_guest_mode is a bit of a wart,
since the map argument is not used elsewhere in the function.  There are
just two callers, and those are also the place where kvm_vcpu_map is
called, so it is cleaner to unmap there.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

All events now inject vmexits before vmentry rather than after vmexit.  Therefore,
exit_required is not set anymore and we can remove it.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This allows exceptions injected by the emulator to be properly delivered
as vmexits.  The code also becomes simpler, because we can just let all
L0-intercepted exceptions go through the usual path.  In particular, our
emulation of the VMX #DB exit qualification is very much simplified,
because the vmexit injection path can use kvm_deliver_exception_payload
to update DR6.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Report interrupts as allowed when the vCPU is in L2 and L2 is being run with
exit-on-interrupts enabled and EFLAGS.IF=1 (either on the host or on the guest
according to VINTR).  Interrupts are always unblocked from L1's perspective
in this case.

While moving nested_exit_on_intr to svm.h, use INTERCEPT_INTR properly instead
of assuming it's zero (which it is of course).
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move the architectural (non-KVM specific) interrupt/NMI/SMI blocking checks
to a separate helper so that they can be used in a future patch by
svm_check_nested_events().

No functional change intended.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Unlike VMX, SVM allows a hypervisor to take a SMI vmexit without having
any special SMM-monitor enablement sequence.  Therefore, it has to be
handled like interrupts and NMIs.  Check for an unblocked SMI in
svm_check_nested_events() so that pending SMIs are correctly prioritized
over IRQs and NMIs when the latter events will trigger VM-Exit.

Note that there is no need to test explicitly for SMI vmexits, because
guests always runs outside SMM and therefore can never get an SMI while
they are blocked.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Report NMIs as allowed when the vCPU is in L2 and L2 is being run with
Exit-on-NMI enabled, as NMIs are always unblocked from L1's perspective
in this case.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Migrate nested guest NMI intercept processing
to new check_nested_events.
Signed-off-by: NCathy Avery <cavery@redhat.com>
Message-Id: <20200414201107.22952-2-cavery@redhat.com>
[Reorder clauses as NMIs have higher priority than IRQs; inject
 immediate vmexit as is now done for IRQ vmexits. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We want to inject vmexits immediately from svm_check_nested_events,
so that the interrupt/NMI window requests happen in inject_pending_event
right after it returns.

This however has the same issue as in vmx_check_nested_events, so
introduce a nested_run_pending flag with the exact same purpose
of delaying vmexit injection after the vmentry.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Clean up some of the patching of kvm_x86_ops, by moving kvm_x86_ops related to
nested virtualization into a separate struct.

As a result, these ops will always be non-NULL on VMX.  This is not a problem:

* check_nested_events is only called if is_guest_mode(vcpu) returns true

* get_nested_state treats VMXOFF state the same as nested being disabled

* set_nested_state fails if you attempt to set nested state while
  nesting is disabled

* nested_enable_evmcs could already be called on a CPU without VMX enabled
  in CPUID.

* nested_get_evmcs_version was fixed in the previous patch
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Drop @invalidate_gpa from ->tlb_flush() and kvm_vcpu_flush_tlb() now
that all callers pass %true for said param, or ignore the param (SVM has
an internal call to svm_flush_tlb() in svm_flush_tlb_guest that somewhat
arbitrarily passes %false).

Remove __vmx_flush_tlb() as it is no longer used.

No functional change intended.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200320212833.3507-17-sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move the SEV specific parts of svm.c into the new sev.c file.
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Message-Id: <20200324094154.32352-5-joro@8bytes.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>