KVM and perf have a special backdoor mechanism to report the IP for interrupts
re-executed after vm exit. This works for the NMIs that perf normally uses.

However when perf is in timer mode it doesn't work because the timer interrupt
doesn't get this special treatment. This is common when KVM is running
nested in another hypervisor which may not implement the PMU, so only
timer mode is available.

Call the functions to set up the backdoor IP also for non NMI interrupts.

I renamed the functions to set up the backdoor IP reporting to be more
appropiate for their new use.  The SVM change is only compile tested.

v2: Moved the functions inline.
For the normal interrupt case the before/after functions are now
called from x86.c, not arch specific code.
For the NMI case we still need to call it in the architecture
specific code, because it's already needed in the low level *_run
functions.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
[Removed unnecessary calls from arch handle_external_intr. - Radim]
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

Add struct kvm_svm, which is analagous to struct vcpu_svm, along with
a helper to_kvm_svm() to retrieve kvm_svm from a struct kvm *.  Move
the SVM specific variables and struct definitions out of kvm_arch
and into kvm_svm.

Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add kvm_x86_ops->set_identity_map_addr and set ept_identity_map_addr
in VMX specific code so that ept_identity_map_addr can be moved out
of 'struct kvm_arch' in a future patch.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Define kvm_arch_[alloc|free]_vm in x86 as pass through functions
to new kvm_x86_ops vm_alloc and vm_free, and move the current
allocation logic as-is to SVM and VMX.  Vendor specific alloc/free
functions set the stage for SVM/VMX wrappers of 'struct kvm',
which will allow us to move the growing number of SVM/VMX specific
member variables out of 'struct kvm_arch'.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Allow to disable pause loop exit/pause filtering on a per VM basis.

If some VMs have dedicated host CPUs, they won't be negatively affected
due to needlessly intercepted PAUSE instructions.

Thanks to Jan H. Schönherr's initial patch.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NWanpeng Li <wanpengli@tencent.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NWanpeng Li <wanpengli@tencent.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If KVM enable_vmware_backdoor module parameter is set,
the commit change VMX to now intercept #GP instead of being directly
deliviered from CPU to guest.

It is done to support access to VMware Backdoor I/O ports
even if TSS I/O permission denies it.
In that case:
1. A #GP will be raised and intercepted.
2. #GP intercept handler will simulate I/O port access instruction.
3. I/O port access instruction simulation will allow access to VMware
backdoor ports specifically even if TSS I/O permission bitmap denies it.

Note that the above change introduce slight performance hit as now #GPs
are now not deliviered directly from CPU to guest but instead
cause #VMExit and instruction emulation.
However, this behavior is introduced only when enable_vmware_backdoor
KVM module parameter is set.
Signed-off-by: NLiran Alon <liran.alon@oracle.com>
Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add kvm_fast_pio() to consolidate duplicate code in VMX and SVM.
Unexport kvm_fast_pio_in() and kvm_fast_pio_out().
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Linux (among the others) has checks to make sure that certain features
aren't enabled on a certain family/model/stepping if the microcode version
isn't greater than or equal to a known good version.

By exposing the real microcode version, we're preventing buggy guests that
don't check that they are running virtualized (i.e., they should trust the
hypervisor) from disabling features that are effectively not buggy.
Suggested-by: NFilippo Sironi <sironi@amazon.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

In order to determine if LFENCE is a serializing instruction on AMD
processors, MSR 0xc0011029 (MSR_F10H_DECFG) must be read and the state
of bit 1 checked.  This patch will add support to allow a guest to
properly make this determination.

Add the MSR feature callback operation to svm.c and add MSR 0xc0011029
to the list of MSR-based features.  If LFENCE is serializing, then the
feature is supported, allowing the hypervisor to set the value of the
MSR that guest will see.  Support is also added to write (hypervisor only)
and read the MSR value for the guest.  A write by the guest will result in
a #GP.  A read by the guest will return the value as set by the host.  In
this way, the support to expose the feature to the guest is controlled by
the hypervisor.
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

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: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
[Tweaked documentation. - Radim]
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

The SEV LAUNCH_SECRET command fails with error code 'invalid param'
because we missed filling the guest and header system physical address
while issuing the command.

Fixes: 9f5b5b95 (KVM: SVM: Add support for SEV LAUNCH_SECRET command)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-kernel@vger.kernel.org
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

RSM instruction is used by the SMM handler to return from SMM mode.
Currently, rsm causes a #UD - which results in instruction fetch, decode,
and emulate. By installing the RSM intercept we can avoid the instruction
fetch since we know that #VMEXIT was due to rsm.

The patch is required for the SEV guest, because in case of SEV guest
memory is encrypted with guest-specific key and hypervisor will not
able to fetch the instruction bytes from the guest memory.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Using the access_ok() to validate the input before issuing the SEV
command does not buy us anything in this case. If userland is
giving us a garbage pointer then copy_to_user() will catch it when we try
to return the measurement.
Suggested-by: NAl Viro <viro@ZenIV.linux.org.uk>
Fixes: 0d0736f7 (KVM: SVM: Add support for KVM_SEV_LAUNCH_MEASURE ...)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-kernel@vger.kernel.org
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

vmx_vcpu_run() and svm_vcpu_run() are large functions, and giving
branch hints to the compiler can actually make a substantial cycle
difference by keeping the fast path contiguous in memory.

With this optimization, the retpoline-guest/retpoline-host case is
about 50 cycles faster.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: KarimAllah Ahmed <karahmed@amazon.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180222154318.20361-3-pbonzini@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Having a paravirt indirect call in the IBRS restore path is not a
good idea, since we are trying to protect from speculative execution
of bogus indirect branch targets.  It is also slower, so use
native_wrmsrl() on the vmentry path too.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: KarimAllah Ahmed <karahmed@amazon.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: d28b387f
Link: http://lkml.kernel.org/r/20180222154318.20361-2-pbonzini@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

[ Based on a patch from Paolo Bonzini <pbonzini@redhat.com> ]

... basically doing exactly what we do for VMX:

- Passthrough SPEC_CTRL to guests (if enabled in guest CPUID)
- Save and restore SPEC_CTRL around VMExit and VMEntry only if the guest
  actually used it.
Signed-off-by: NKarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NDarren Kenny <darren.kenny@oracle.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: kvm@vger.kernel.org
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Link: https://lkml.kernel.org/r/1517669783-20732-1-git-send-email-karahmed@amazon.de

The Indirect Branch Predictor Barrier (IBPB) is an indirect branch
control mechanism. It keeps earlier branches from influencing
later ones.

Unlike IBRS and STIBP, IBPB does not define a new mode of operation.
It's a command that ensures predicted branch targets aren't used after
the barrier. Although IBRS and IBPB are enumerated by the same CPUID
enumeration, IBPB is very different.

IBPB helps mitigate against three potential attacks:

* Mitigate guests from being attacked by other guests.
  - This is addressed by issing IBPB when we do a guest switch.

* Mitigate attacks from guest/ring3->host/ring3.
  These would require a IBPB during context switch in host, or after
  VMEXIT. The host process has two ways to mitigate
  - Either it can be compiled with retpoline
  - If its going through context switch, and has set !dumpable then
    there is a IBPB in that path.
    (Tim's patch: https://patchwork.kernel.org/patch/10192871)
  - The case where after a VMEXIT you return back to Qemu might make
    Qemu attackable from guest when Qemu isn't compiled with retpoline.
  There are issues reported when doing IBPB on every VMEXIT that resulted
  in some tsc calibration woes in guest.

* Mitigate guest/ring0->host/ring0 attacks.
  When host kernel is using retpoline it is safe against these attacks.
  If host kernel isn't using retpoline we might need to do a IBPB flush on
  every VMEXIT.

Even when using retpoline for indirect calls, in certain conditions 'ret'
can use the BTB on Skylake-era CPUs. There are other mitigations
available like RSB stuffing/clearing.

* IBPB is issued only for SVM during svm_free_vcpu().
  VMX has a vmclear and SVM doesn't.  Follow discussion here:
  https://lkml.org/lkml/2018/1/15/146

Please refer to the following spec for more details on the enumeration
and control.

Refer here to get documentation about mitigations.

https://software.intel.com/en-us/side-channel-security-support

[peterz: rebase and changelog rewrite]
[karahmed: - rebase
           - vmx: expose PRED_CMD if guest has it in CPUID
           - svm: only pass through IBPB if guest has it in CPUID
           - vmx: support !cpu_has_vmx_msr_bitmap()]
           - vmx: support nested]
[dwmw2: Expose CPUID bit too (AMD IBPB only for now as we lack IBRS)
        PRED_CMD is a write-only MSR]
Signed-off-by: NAshok Raj <ashok.raj@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: NKarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: kvm@vger.kernel.org
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: http://lkml.kernel.org/r/1515720739-43819-6-git-send-email-ashok.raj@intel.com
Link: https://lkml.kernel.org/r/1517522386-18410-3-git-send-email-karahmed@amazon.de

sync_pir_to_irr() is only called if vcpu->arch.apicv_active()==true.
In case it is false, VMX code make sure to set sync_pir_to_irr
to NULL.

Therefore, having SVM stubs allows to remove check for if
sync_pir_to_irr != NULL from all calling sites.
Signed-off-by: NLiran Alon <liran.alon@oracle.com>
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: NLiam Merwick <liam.merwick@oracle.com>
[Return highest IRR in the SVM case. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

Introduce a new bool invalidate_gpa argument to kvm_x86_ops->tlb_flush,
it will be used by later patches to just flush guest tlb.

For VMX, this will use INVVPID instead of INVEPT, which will invalidate
combined mappings while keeping guest-physical mappings.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

In accordance with the Intel and AMD documentation, we need to overwrite
all entries in the RSB on exiting a guest, to prevent malicious branch
target predictions from affecting the host kernel. This is needed both
for retpoline and for IBRS.

[ak: numbers again for the RSB stuffing labels]
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515755487-8524-1-git-send-email-dwmw@amazon.co.uk

This reverts commits ae1f5767
and ac9b305c.

If the hardware doesn't support MOVBE, but L0 sets CPUID.01H:ECX.MOVBE
in L1's emulated CPUID information, then L1 is likely to pass that
CPUID bit through to L2. L2 will expect MOVBE to work, but if L1
doesn't intercept #UD, then any MOVBE instruction executed in L2 will
raise #UD, and the exception will be delivered in L2.

Commit ac9b305c is a better and more
complete version of ae1f5767 ("KVM: nVMX: Do not emulate #UD while
in guest mode"); however, neither considers the above case.
Suggested-by: NJim Mattson <jmattson@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Guest GPR values are live in the hardware GPRs at VM-exit.  Do not
leave any guest values in hardware GPRs after the guest GPR values are
saved to the vcpu_vmx structure.

This is a partial mitigation for CVE 2017-5715 and CVE 2017-5753.
Specifically, it defeats the Project Zero PoC for CVE 2017-5715.
Suggested-by: NEric Northup <digitaleric@google.com>
Signed-off-by: NJim Mattson <jmattson@google.com>
Reviewed-by: NEric Northup <digitaleric@google.com>
Reviewed-by: NBenjamin Serebrin <serebrin@google.com>
Reviewed-by: NAndrew Honig <ahonig@google.com>
[Paolo: Add AMD bits, Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The User-Mode Instruction Prevention feature present in recent Intel
processor prevents a group of instructions (sgdt, sidt, sldt, smsw, and
str) from being executed with CPL > 0. Otherwise, a general protection
fault is issued.

UMIP instructions in general are also able to trigger vmexits, so we can
actually emulate UMIP on older processors.  This commit sets up the
infrastructure so that kvm-intel.ko and kvm-amd.ko can set the UMIP
feature bit for CPUID even if the feature is not actually available
in hardware.
Reviewed-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

On AMD platforms, under certain conditions insn_len may be zero on #NPF.
This can happen if a guest gets a page-fault on data access but the HW
table walker is not able to read the instruction page (e.g instruction
page is not present in memory).

Typically, when insn_len is zero, x86_emulate_instruction() walks the
guest page table and fetches the instruction bytes from guest memory.
When SEV is enabled, the guest memory is encrypted with guest-specific
key hence hypervisor will not able to fetch the instruction bytes.
In those cases we simply restart the guest.

I have encountered this issue when running kernbench inside the guest.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>

On #UD, x86_emulate_instruction() fetches the data from guest memory and
decodes the instruction bytes to assist further. When SEV is enabled, the
instruction bytes will be encrypted using the guest-specific key and the
hypervisor will no longer able to fetch the instruction bytes to assist
UD handling. By not installing intercept we let the guest receive and
handle #UD.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>

When SEV is active, on #VMEXIT the  page fault address will contain the
C-bit. We must clear the C-bit before handling the fault.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>

The SEV memory encryption engine uses a tweak such that two identical
plaintext pages at different location will have different ciphertext.
So swapping or moving ciphertext of two pages will not result in
plaintext being swapped. Relocating (or migrating) physical backing
pages for a SEV guest will require some additional steps. The current SEV
key management spec does not provide commands to swap or migrate (move)
ciphertext pages. For now, we pin the guest memory registered through
KVM_MEMORY_ENCRYPT_REG_REGION ioctl.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>

The command is used for injecting a secret into the guest memory region.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The command copies a plaintext into guest memory and encrypts it using
the VM encryption key. The command will be used for debug purposes
(e.g setting breakpoints through gdbserver)

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>

The command is used for decrypting a guest memory region for debug
purposes.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The command is used for querying the SEV guest information.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The command is used for finializing the SEV guest launch process.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The command is used to retrieve the measurement of contents encrypted
through the KVM_SEV_LAUNCH_UPDATE_DATA command.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The command is used for encrypting the guest memory region using the VM
encryption key (VEK) created during KVM_SEV_LAUNCH_START.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The KVM_SEV_LAUNCH_START command is used to create a memory encryption
context within the SEV firmware. In order to do so, the guest owner
should provide the guest's policy, its public Diffie-Hellman (PDH) key
and session information. The command implements the LAUNCH_START flow
defined in SEV spec Section 6.2.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

SEV hardware uses ASIDs to associate a memory encryption key with a
guest VM. During guest creation, a SEV VM uses the SEV_CMD_ACTIVATE
command to bind a particular ASID to the guest. Lets make sure that the
VMCB is programmed with the bound ASID before a VMRUN.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The command initializes the SEV platform context and allocates a new ASID
for this guest from the SEV ASID pool. The firmware must be initialized
before we issue any guest launch commands to create a new memory encryption
context.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>

The module parameter can be used to control the SEV feature support.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NBrijesh Singh <brijesh.singh@amd.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>