Simplify LAPIC TMCCT calculation by using hrtimer provided
function to query remaining time until expiration.

Fixes host hang with nested ESX.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Software are not allow to access device MMIO using cacheable memory type, the
patch limit MMIO region with UC and WC(guest can select WC using PAT and
PCD/PWT).
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

There is no point in doing the ready_for_nmi_injection/
request_nmi_window dance with user space. First, we don't do this for
in-kernel irqchip anyway, while the code path is the same as for user
space irqchip mode. And second, there is nothing to loose if a pending
NMI is overwritten by another one (in contrast to IRQs where we have to
save the number). Actually, there is even the risk of raising spurious
NMIs this way because the reason for the held-back NMI might already be
handled while processing the first one.

Therefore this patch creates a simplified user space NMI injection
interface, exporting it under KVM_CAP_USER_NMI and dropping the old
KVM_CAP_NMI capability. And this time we also take care to provide the
interface only on archs supporting NMIs via KVM (right now only x86).
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

As with the kernel irqchip, don't allow an NMI to stomp over an already
injected IRQ; instead wait for the IRQ injection to be completed.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Impact: make global function static

  arch/x86/kvm/vmx.c:134:3: warning: symbol 'vmx_capability' was not declared. Should it be static?
Signed-off-by: NHannes Eder <hannes@hanneseder.net>
Signed-off-by: NAvi Kivity <avi@redhat.com>

If we're injecting an interrupt, and another one is pending, request
an interrupt window notification so we don't have excess latency on the
second interrupt.

This shouldn't happen in practice since an EOI will be issued, giving a second
chance to request an interrupt window, but...
Signed-off-by: NAvi Kivity <avi@redhat.com>

Along with some comments on why it is different from the core cpu_vmxoff()
function.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

It will be used by core code on kdump and reboot, to disable
vmx if needed.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

vmx.h will be used by core code that is independent of KVM, so I am
moving it outside the arch/x86/kvm directory.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

If emulate_invalid_guest_state is enabled, the emulator is called
when guest state is invalid.  Until now, we reported an mmio failure
when emulate_instruction() returned EMULATE_DO_MMIO.  This patch adds
the case where emulate_instruction() failed and an MMIO emulation
is needed.
Signed-off-by: NGuillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: NAvi Kivity <avi@redhat.com>

If we call the emulator we shouldn't call skip_emulated_instruction()
in the first place, since the emulator already computes the next rip
for us. Thus we move ->skip_emulated_instruction() out of
kvm_emulate_pio() and into handle_io() (and the svm equivalent). We
also replaced "return 0" by "break" in the "do_io:" case because now
the shadow register state needs to be committed. Otherwise eip will never
be updated.
Signed-off-by: NGuillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: NAvi Kivity <avi@redhat.com>

PCI device assignment would map guest MMIO spaces as separate slot, so it is
possible that the device has more than 2 MMIO spaces and overwrite current
private memslot.

The patch move private memory slot to the top of userspace visible memory slots.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The effective memory type of EPT is the mixture of MSR_IA32_CR_PAT and memory
type field of EPT entry.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

GUEST_PAT support is a new feature introduced by Intel Core i7 architecture.
With this, cpu would save/load guest and host PAT automatically, for EPT memory
type in guest depends on MSR_IA32_CR_PAT.

Also add save/restore for MSR_IA32_CR_PAT.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Older VMX supporting CPUs do not provide the "Virtual NMI" feature for
tracking the NMI-blocked state after injecting such events. For now
KVM is unable to inject NMIs on those CPUs.

Derived from Sheng Yang's suggestion to use the IRQ window notification
for detecting the end of NMI handlers, this patch implements virtual
NMI support without impact on the host's ability to receive real NMIs.
The downside is that the given approach requires some heuristics that
can cause NMI nesting in vary rare corner cases.

The approach works as follows:
 - inject NMI and set a software-based NMI-blocked flag
 - arm the IRQ window start notification whenever an NMI window is
   requested
 - if the guest exits due to an opening IRQ window, clear the emulated
   NMI-blocked flag
 - if the guest net execution time with NMI-blocked but without an IRQ
   window exceeds 1 second, force NMI-blocked reset and inject anyway

This approach covers most practical scenarios:
 - succeeding NMIs are seperated by at least one open IRQ window
 - the guest may spin with IRQs disabled (e.g. due to a bug), but
   leaving the NMI handler takes much less time than one second
 - the guest does not rely on strict ordering or timing of NMIs
   (would be problematic in virtualized environments anyway)

Successfully tested with the 'nmi n' monitor command, the kgdbts
testsuite on smp guests (additional patches required to add debug
register support to kvm) + the kernel's nmi_watchdog=1, and a Siemens-
specific board emulation (+ guest) that comes with its own NMI
watchdog mechanism.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This patch adds the required bits to the VMX side for user space
injected NMIs. As with the preexisting in-kernel irqchip support, the
CPU must provide the "virtual NMI" feature for proper tracking of the
NMI blocking state.

Based on the original patch by Sheng Yang.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NSheng Yang <sheng.yang@intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Fix NMI injection in real-mode with the same pattern we perform IRQ
injection.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

do_interrupt_requests and vmx_intr_assist go different way for
achieving the same: enabling the nmi/irq window start notification.
Unify their code over enable_{irq|nmi}_window, get rid of a redundant
call to enable_intr_window instead of direct enable_nmi_window
invocation and unroll enable_intr_window for both in-kernel and user
space irq injection accordingly.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

There are currently two ways in VMX to check if an IRQ or NMI can be
injected:
 - vmx_{nmi|irq}_enabled and
 - vcpu.arch.{nmi|interrupt}_window_open.
Even worse, one test (at the end of vmx_vcpu_run) uses an inconsistent,
likely incorrect logic.

This patch consolidates and unifies the tests over
{nmi|interrupt}_window_open as cache + vmx_update_window_states
for updating the cache content.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Properly set GUEST_INTR_STATE_NMI and reset nmi_injected when a
task-switch vmexit happened due to a task gate being used for handling
NMIs. Also avoid the false warning about valid vectoring info in
kvm_handle_exit.

Based on original patch by Gleb Natapov.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

irq_window_exits only tracks IRQ window exits due to user space
requests, nmi_window_exits include all exits. The latter makes more
sense, so let's adjust irq_window_exits accounting.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

If an interrupt cannot be injected for some reason (say, page fault
when fetching the IDT descriptor), the interrupt is marked for
reinjection.  However, if an NMI is queued at this time, the NMI
will be injected instead and the NMI will be lost.

Fix by deferring the NMI injection until the interrupt has been
injected successfully.

Analyzed by Jan Kiszka.
Signed-off-by: NAvi Kivity <avi@redhat.com>

There is a potential issue that, when guest using pagetable without vmexit when
EPT enabled, guest would use PAT/PCD/PWT bits to index PAT msr for it's memory,
which would be inconsistent with host side and would cause host MCE due to
inconsistent cache attribute.

The patch set IGMT bit in EPT entry to ignore guest PAT and use WB as default
memory type to protect host (notice that all memory mapped by KVM should be WB).
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Manually disabling EPT via module option fails to re-enable INVLPG
exiting.
Reported-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

With pages out of sync invlpg needs to be trapped. For now simply nuke
the entry.

Untested on AMD.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Convert gfn_to_pfn to use get_user_pages_fast, which can do lockless
pagetable lookups on x86. Kernel compilation on 4-way guest is 3.7%
faster on VMX.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NSheng Yang <sheng.yang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Commit 1c0f4f5011829dac96347b5f84ba37c2252e1e08 left a useless access
of VM_ENTRY_INTR_INFO_FIELD in vmx_intr_assist behind. Clean this up.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

These can help show whether a guest is making progress or not.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This is more emulation friendly, if not 100% correct.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Real mode cs is a data segment, not a code segment.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch modifies mode switching and vmentry function in order to
drive invalid guest state emulation.
Signed-off-by: NMohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This adds the invalid guest state handler function which invokes the x86
emulator until getting the guest to a VMX-friendly state.

[avi: leave atomic context if scheduling]
[guillaume: return to atomic context correctly]
Signed-off-by: NLaurent Vivier <laurent.vivier@bull.net>
Signed-off-by: NGuillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: NMohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

The patch adds the module parameter required to enable emulating invalid
guest state, as well as the emulation_required flag used to drive
emulation whenever needed.
Signed-off-by: NMohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch adds functions to check whether guest state is VMX compliant.
Signed-off-by: NMohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NSheng Yang <sheng.yang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Usually HOST_RSP retains its value across guest entries.  Take advantage
of this and avoid a vmwrite() when this is so.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NAvi Kivity <avi@qumranet.com>