VM_ENTRY_IA32E_MODE and VM_{ENTRY,EXIT}_LOAD_IA32_EFER will be
explicitly set/cleared as needed by vmx_set_efer(), but attempt
to get the bits set correctly when intializing the control fields.
Setting the value correctly can avoid multiple VMWrites.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Do not unconditionally call clear_atomic_switch_msr() when updating
EFER.  This adds up to four unnecessary VMWrites in the case where
guest_efer != host_efer, e.g. if the load_on_{entry,exit} bits were
already set.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reset the vm_{entry,exit}_controls_shadow variables as well as the
segment cache after loading a new VMCS in vmx_switch_vmcs().  The
shadows/cache track VMCS data, i.e. they're stale every time we
switch to a new VMCS regardless of reason.

This fixes a bug where stale control shadows would be consumed after
a nested VMExit due to a failed consistency check.
Suggested-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Write VM_EXIT_CONTROLS using vm_exit_controls_init() when configuring
vmcs02, otherwise vm_exit_controls_shadow will be stale.  EFER in
particular can be corrupted if VM_EXIT_LOAD_IA32_EFER is not updated
due to an incorrect shadow optimization, which can crash L0 due to
EFER not being loaded on exit.  This does not occur with the current
code base simply because update_transition_efer() unconditionally
clears VM_EXIT_LOAD_IA32_EFER before conditionally setting it, and
because a nested guest always starts with VM_EXIT_LOAD_IA32_EFER
clear, i.e. we'll only ever unnecessarily clear the bit.  That is,
until someone optimizes update_transition_efer()...
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

An invalid EPTP causes a VMFail(VMXERR_ENTRY_INVALID_CONTROL_FIELD),
not a VMExit.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Invalid host state related to loading EFER on VMExit causes a
VMFail(VMXERR_ENTRY_INVALID_HOST_STATE_FIELD), not a VMExit.
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

update_memslots() is only called by __kvm_set_memory_region(), in which
"change" is calculated and indicates how to adjust slots->used_slots

  * increase by one if it is KVM_MR_CREATE
  * decrease by one if it is KVM_MR_DELETE
  * not change for others

This patch adjusts slots->used_slots in update_memslots() based on "change"
value instead of re-calculate those states again.
Signed-off-by: NWei Yang <richard.weiyang@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When bit 3 (corresponding to CR0.TS) of the VMCS12 cr0_guest_host_mask
field is clear, the VMCS12 guest_cr0 field does not necessarily hold
the current value of the L2 CR0.TS bit, so the code that checked for
L2's CR0.TS bit being set was incorrect. Moreover, I'm not sure that
the CR0.TS check was adequate. (What if L2's CR0.EM was set, for
instance?)

Fortunately, lazy FPU has gone away, so L0 has lost all interest in
intercepting #NM exceptions. See commit bd7e5b08 ("KVM: x86:
remove code for lazy FPU handling"). Therefore, there is no longer any
question of which hypervisor gets first dibs. The #NM VM-exit should
always be reflected to L1. (Note that the corresponding bit must be
set in the VMCS12 exception_bitmap field for there to be an #NM
VM-exit at all.)

Fixes: ccf9844e ("kvm, vmx: Really fix lazy FPU on nested guest")
Reported-by: NAbhiroop Dabral <adabral@paloaltonetworks.com>
Signed-off-by: NJim Mattson <jmattson@google.com>
Reviewed-by: NPeter Shier <pshier@google.com>
Tested-by: NAbhiroop Dabral <adabral@paloaltonetworks.com>
Reviewed-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Using hypercall for sending IPIs is faster because this allows to specify
any number of vCPUs (even > 64 with sparse CPU set), the whole procedure
will take only one VMEXIT.

Current Hyper-V TLFS (v5.0b) claims that HvCallSendSyntheticClusterIpi
hypercall can't be 'fast' (passing parameters through registers) but
apparently this is not true, Windows always uses it as 'fast' so we need
to support that.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

VP inedx almost always matches VCPU and when it does it's faster to walk
the sparse set instead of all vcpus.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This probably doesn't matter much (KVM_MAX_VCPUS is much lower nowadays)
but valid_bank_mask is really u64 and not unsigned long.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In most common cases VP index of a vcpu matches its vcpu index. Userspace
is, however, free to set any mapping it wishes and we need to account for
that when we need to find a vCPU with a particular VP index. To keep search
algorithms optimal in both cases introduce 'num_mismatched_vp_indexes'
counter showing how many vCPUs with mismatching VP index we have. In case
the counter is zero we can assume vp_index == vcpu_idx.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Rename 'hv' to 'hv_vcpu' in kvm_hv_set_msr/kvm_hv_get_msr(); 'hv' is
'reserved' for 'struct kvm_hv' variables across the file.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We can use 'NULL' to represent 'all cpus' case in
kvm_make_vcpus_request_mask() and avoid building vCPU mask with
all vCPUs.
Suggested-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Hyper-V TLFS (5.0b) states:

> Virtual processors are identified by using an index (VP index). The
> maximum number of virtual processors per partition supported by the
> current implementation of the hypervisor can be obtained through CPUID
> leaf 0x40000005. A virtual processor index must be less than the
> maximum number of virtual processors per partition.

Forbid userspace to set VP_INDEX above KVM_MAX_VCPUS. get_vcpu_by_vpidx()
can now be optimized to bail early when supplied vpidx is >= KVM_MAX_VCPUS.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If kvm_apic_map_get_dest_lapic() finds a disabled LAPIC,
it will return with bitmap==0 and (*r == -1) will be returned to
userspace.

QEMU may then record "KVM: injection failed, MSI lost
(Operation not permitted)" in its log, which is quite puzzling.
Reported-by: NPeng Hao <penghao122@sina.com.cn>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Currently, there are two definitions related to huge page, but a little bit
far from each other and seems loosely connected:

 * KVM_NR_PAGE_SIZES defines the number of different size a page could map
 * PT_MAX_HUGEPAGE_LEVEL means the maximum level of huge page

The number of different size a page could map equals the maximum level
of huge page, which is implied by current definition.

While current implementation may not be kind to readers and further
developers:

 * KVM_NR_PAGE_SIZES looks like a stand alone definition at first sight
 * in case we need to support more level, two places need to change

This patch tries to make these two definition more close, so that reader
and developer would feel more comfortable to manipulate.
Signed-off-by: NWei Yang <richard.weiyang@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

is_external_interrupt() is not used now and so remove it.
Signed-off-by: NLan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The code tries to pre-allocate *min* number of objects, so it is ok to
return 0 when the kvm_mmu_memory_cache meets the requirement.
Signed-off-by: NWei Yang <richard.weiyang@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Suggested-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NKrish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: NMark Kanda <mark.kanda@oracle.com>
Reviewed-by: NJim Mattson <jmattson@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

On a 64bits machine, struct is naturally aligned with 8 bytes. Since
kvm_mmu_page member *unsync* and *role* are less then 4 bytes, we can
rearrange the sequence to compace the struct.

As the comment shows, *role* and *gfn* are used to key the shadow page. In
order to keep the comment valid, this patch moves the *unsync* up and
exchange the position of *role* and *gfn*.

From /proc/slabinfo, it shows the size of kvm_mmu_page is 8 bytes less and
with one more object per slap after applying this patch.

    # name            <active_objs> <num_objs> <objsize> <objperslab>
    kvm_mmu_page_header      0           0       168         24

    kvm_mmu_page_header      0           0       160         25
Signed-off-by: NWei Yang <richard.weiyang@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

A VMEnter that VMFails (as opposed to VMExits) does not touch host
state beyond registers that are explicitly noted in the VMFail path,
e.g. EFLAGS.  Host state does not need to be loaded because VMFail
is only signaled for consistency checks that occur before the CPU
starts to load guest state, i.e. there is no need to restore any
state as nothing has been modified.  But in the case where a VMFail
is detected by hardware and not by KVM (due to deferring consistency
checks to hardware), KVM has already loaded some amount of guest
state.  Luckily, "loaded" only means loaded to KVM's software model,
i.e. vmcs01 has not been modified.  So, unwind our software model to
the pre-VMEntry host state.

Not restoring host state in this VMFail path leads to a variety of
failures because we end up with stale data in vcpu->arch, e.g. CR0,
CR4, EFER, etc... will all be out of sync relative to vmcs01.  Any
significant delta in the stale data is all but guaranteed to crash
L1, e.g. emulation of SMEP, SMAP, UMIP, WP, etc... will be wrong.

An alternative to this "soft" reload would be to load host state from
vmcs12 as if we triggered a VMExit (as opposed to VMFail), but that is
wildly inconsistent with respect to the VMX architecture, e.g. an L1
VMM with separate VMExit and VMFail paths would explode.

Note that this approach does not mean KVM is 100% accurate with
respect to VMX hardware behavior, even at an architectural level
(the exact order of consistency checks is microarchitecture specific).
But 100% emulation accuracy isn't the goal (with this patch), rather
the goal is to be consistent in the information delivered to L1, e.g.
a VMExit should not fall-through VMENTER, and a VMFail should not jump
to HOST_RIP.

This technically reverts commit "5af41573 (KVM: nVMX: Fix mmu
context after VMLAUNCH/VMRESUME failure)", but retains the core
aspects of that patch, just in an open coded form due to the need to
pull state from vmcs01 instead of vmcs12.  Restoring host state
resolves a variety of issues introduced by commit "4f350c6d
(kvm: nVMX: Handle deferred early VMLAUNCH/VMRESUME failure properly)",
which remedied the incorrect behavior of treating VMFail like VMExit
but in doing so neglected to restore arch state that had been modified
prior to attempting nested VMEnter.

A sample failure that occurs due to stale vcpu.arch state is a fault
of some form while emulating an LGDT (due to emulated UMIP) from L1
after a failed VMEntry to L3, in this case when running the KVM unit
test test_tpr_threshold_values in L1.  L0 also hits a WARN in this
case due to a stale arch.cr4.UMIP.

L1:
  BUG: unable to handle kernel paging request at ffffc90000663b9e
  PGD 276512067 P4D 276512067 PUD 276513067 PMD 274efa067 PTE 8000000271de2163
  Oops: 0009 [#1] SMP
  CPU: 5 PID: 12495 Comm: qemu-system-x86 Tainted: G        W         4.18.0-rc2+ #2
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:native_load_gdt+0x0/0x10

  ...

  Call Trace:
   load_fixmap_gdt+0x22/0x30
   __vmx_load_host_state+0x10e/0x1c0 [kvm_intel]
   vmx_switch_vmcs+0x2d/0x50 [kvm_intel]
   nested_vmx_vmexit+0x222/0x9c0 [kvm_intel]
   vmx_handle_exit+0x246/0x15a0 [kvm_intel]
   kvm_arch_vcpu_ioctl_run+0x850/0x1830 [kvm]
   kvm_vcpu_ioctl+0x3a1/0x5c0 [kvm]
   do_vfs_ioctl+0x9f/0x600
   ksys_ioctl+0x66/0x70
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x4f/0x100
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

L0:
  WARNING: CPU: 2 PID: 3529 at arch/x86/kvm/vmx.c:6618 handle_desc+0x28/0x30 [kvm_intel]
  ...
  CPU: 2 PID: 3529 Comm: qemu-system-x86 Not tainted 4.17.2-coffee+ #76
  Hardware name: Intel Corporation Kabylake Client platform/KBL S
  RIP: 0010:handle_desc+0x28/0x30 [kvm_intel]

  ...

  Call Trace:
   kvm_arch_vcpu_ioctl_run+0x863/0x1840 [kvm]
   kvm_vcpu_ioctl+0x3a1/0x5c0 [kvm]
   do_vfs_ioctl+0x9f/0x5e0
   ksys_ioctl+0x66/0x70
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x49/0xf0
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 5af41573 (KVM: nVMX: Fix mmu context after VMLAUNCH/VMRESUME failure)
Fixes: 4f350c6d (kvm: nVMX: Handle deferred early VMLAUNCH/VMRESUME failure properly)
Cc: Jim Mattson <jmattson@google.com>
Cc: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

According to volume 3 of the SDM, bits 63:15 and 12:4 of the exit
qualification field for debug exceptions are reserved (cleared to
0). However, the SDM is incorrect about bit 16 (corresponding to
DR6.RTM). This bit should be set if a debug exception (#DB) or a
breakpoint exception (#BP) occurred inside an RTM region while
advanced debugging of RTM transactional regions was enabled. Note that
this is the opposite of DR6.RTM, which "indicates (when clear) that a
debug exception (#DB) or breakpoint exception (#BP) occurred inside an
RTM region while advanced debugging of RTM transactional regions was
enabled."

There is still an issue with stale DR6 bits potentially being
misreported for the current debug exception.  DR6 should not have been
modified before vectoring the #DB exception, and the "new DR6 bits"
should be available somewhere, but it was and they aren't.

Fixes: b96fb439 ("KVM: nVMX: fixes to nested virt interrupt injection")
Signed-off-by: NJim Mattson <jmattson@google.com>
Reviewed-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Let's add the 40 PA-bit versions of the VM modes, that AArch64
should have been using, so we can extend the dirty log test without
breaking things.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

While we're messing with the code for the port and to support guest
page sizes that are less than the host page size, we also make some
code formatting cleanups and apply sync_global_to_guest().
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Rename VM_MODE_FLAT48PG to be more descriptive of its config and add a
new config that has the same parameters, except with 64K pages.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This code adds VM and VCPU setup code for the VM_MODE_FLAT48PG mode.
The VM_MODE_FLAT48PG isn't yet fully supportable, as it defines the
guest physical address limit as 52-bits, and KVM currently only
supports guests with up to 40-bit physical addresses (see
KVM_PHYS_SHIFT). VM_MODE_FLAT48PG will work fine, though, as long as
no >= 40-bit physical addresses are used.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Tidy up kvm-util code: code/comment formatting, remove unused code,
and move x86 specific code out. We also move vcpu_dump() out of
common code, because not all arches (AArch64) have KVM_GET_REGS.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Rework the guest exit to userspace code to generalize the concept
into what it is, a "hypercall to userspace", and provide two
implementations of it: the PortIO version currently used, but only
useable by x86, and an MMIO version that other architectures (except
s390) can use.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Guest code may want to call functions that have variable arguments.
To do so, we either need to compile with -mno-sse or enable SSE in
the VCPUs. As it should be pretty safe to turn on the feature, and
-mno-sse would make linking test code with standard libraries
difficult, we choose the feature enabling.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In cloud environment, lapic_timer_advance_ns is needed to be tuned for every CPU
generations, and every host kernel versions(the kvm-unit-tests/tscdeadline_latency.flat
is 5700 cycles for upstream kernel and 9600 cycles for our 3.10 product kernel,
both preemption_timer=N, Skylake server).

This patch adds the capability to automatically tune lapic_timer_advance_ns
step by step, the initial value is 1000ns as 'commit d0659d94 ("KVM: x86:
add option to advance tscdeadline hrtimer expiration")' recommended, it will be
reduced when it is too early, and increased when it is too late. The guest_tsc
and tsc_deadline are hard to equal, so we assume we are done when the delta
is within a small scope e.g. 100 cycles. This patch reduces latency
(kvm-unit-tests/tscdeadline_latency, busy waits, preemption_timer enabled)
from ~2600 cyles to ~1200 cyles on our Skylake server.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If L1 uses VPID, it expects TLB to not be flushed on L1<->L2
transitions. However, code currently flushes TLB nonetheless if we
didn't allocate a vpid02 for L2. As in this case,
vmcs02->vpid == vmcs01->vpid == vmx->vpid.

But, if L1 uses EPT, TLB entires populated by L2 are tagged with EPTP02
while TLB entries populated by L1 are tagged with EPTP01.
Therefore, we can also avoid TLB flush if L1 uses VPID and EPT.
Reviewed-by: NMihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: NDarren Kenny <darren.kenny@oracle.com>
Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

All VPID12s used on a given L1 vCPU is translated to a single
VPID02 (vmx->nested.vpid02 or vmx->vpid). Therefore, on L1->L2 VMEntry,
we need to invalidate linear and combined mappings tagged by
VPID02 in case L1 uses VPID and vmcs12->vpid was changed since
last L1->L2 VMEntry.

However, current code invalidates the wrong mappings as it calls
__vmx_flush_tlb() with invalidate_gpa parameter set to true which will
result in invalidating combined and guest-physical mappings tagged with
active EPTP which is EPTP01.

Similarly, INVVPID emulation have the exact same issue.

Fix both issues by just setting invalidate_gpa parameter to false which
will result in invalidating linear and combined mappings tagged with
given VPID02 as required.
Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: NMark Kanda <mark.kanda@oracle.com>
Signed-off-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In case L0 didn't allocate vmx->nested.vpid02 for L2,
vmcs02->vpid is set to vmx->vpid.
Consider this case when emulating L1 INVVPID in L0.
Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: NMark Kanda <mark.kanda@oracle.com>
Signed-off-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>