When executing a test program called "crashme", we found the KVM guest cannot
survive more than ten seconds, then encounterd kernel panic. The basic concept
of "crashme" is generating random assembly code and trying to execute it.

After some fixes on emulator insn validity judgment, we found it's hard to
get the current emulator handle the invalid instructions correctly, for the
#UD trap for hypercall patching caused troubles. The problem is, if the opcode
itself was OK, but combination of opcode and modrm_reg was invalid, and one
operand of the opcode was memory (SrcMem or DstMem), the emulator will fetch
the memory operand first rather than checking the validity, and may encounter
an error there. For example, ".byte 0xfe, 0x34, 0xcd" has this problem.

In the patch, we simply check that if the invalid opcode wasn't vmcall/vmmcall,
then return from emulate_instruction() and inject a #UD to guest. With the
patch, the guest had been running for more than 12 hours.
Signed-off-by: NFeng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: NSheng Yang <sheng.yang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Do not hold kvm->lock mutex across the entire pagefault code,
only acquire it in places where it is necessary, such as mmu
hash list, active list, rmap and parent pte handling.

Allow concurrent guest walkers by switching walk_addr() to use
mmap_sem in read-mode.

And get rid of the lockless __gfn_to_page.

[avi: move kvm_mmu_pte_write() locking inside the function]
[avi: add locking for real mode]
[avi: fix cmpxchg locking]
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

FlexPriority accelerates the tpr without any patching.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This adds a mechanism for exposing the virtual apic tpr to the guest, and a
protocol for letting the guest update the tpr without causing a vmexit if
conditions allow (e.g. there is no interrupt pending with a higher priority
than the new tpr).
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Add a facility to report on accesses to the local apic tpr even if the
local apic is emulated in the kernel.  This is basically a hack that
allows userspace to patch Windows which tends to bang on the tpr a lot.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This can help diagnosing what the guest is trying to do.  In many cases
we can get away with partial emulation of msrs.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

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

Moving kvm_vcpu_kick() to x86.c. Since it should be
common for all archs, put its declarations in <linux/kvm_host.h>
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This paves the way for multiple architecture support.  Note that while
ioapic.c could potentially be shared with ia64, it is also moved.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patches moves two fields vpid and vioapic to kvm_arch
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patches moves mmu-related fields to kvm_arch.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patches create kvm_arch to hold arch-specific kvm fileds
and moves fields naliases and aliases to kvm_arch.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Since these functions need to know the details of kvm or kvm_vcpu structure,
it can't be put in x86.h.  Create mmu.h to hold them.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Move all the architecture-specific fields in kvm_vcpu into a new struct
kvm_vcpu_arch.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Emulate cmpxchg8b atomically on i386. This is required to avoid a guest
pte walker from seeing a splitted write.

[avi: make it compile]
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This patch adds code to emulate the access to the cr8 register to the x86
instruction emulator in kvm.  This is needed on svm, where there is no
hardware decode for control register access.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NMarkus Rechberger <markus.rechberger@amd.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

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

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

Instead of each subarch doing its own thing, add an API for queuing an
injection, and manage failed exception injection centerally (i.e., if
an inject failed due to a shadow page fault, we need to requeue it).
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Other archs doesn't need it.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Previous patches have removed the dependency on cr2; we can now stop passing
it to the emulator and rename uses to 'memop'.
Signed-off-by: NSheng Yang <sheng.yang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

mmio was already handled in kvm_arch_vcpu_ioctl_run(), so no need to check
again.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Non-x86 archs don't need this mechanism. Move it to arch, and
keep its interface in common.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

The current cpuid management suffers from several problems, which inhibit
passing through the host feature set to the guest:

 - No way to tell which features the host supports

  While some features can be supported with no changes to kvm, others
  need explicit support.  That means kvm needs to vet the feature set
  before it is passed to the guest.

 - No support for indexed or stateful cpuid entries

  Some cpuid entries depend on ecx as well as on eax, or on internal
  state in the processor (running cpuid multiple times with the same
  input returns different output).  The current cpuid machinery only
  supports keying on eax.

 - No support for save/restore/migrate

  The internal state above needs to be exposed to userspace so it can
  be saved or migrated.

This patch adds extended cpuid support by means of three new ioctls:

 - KVM_GET_SUPPORTED_CPUID: get all cpuid entries the host (and kvm)
   supports

 - KVM_SET_CPUID2: sets the vcpu's cpuid table

 - KVM_GET_CPUID2: gets the vcpu's cpuid table, including hidden state

[avi: fix original KVM_SET_CPUID not removing nx on non-nx hosts as it did
      before]
Signed-off-by: NDan Kenigsberg <danken@qumranet.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

If the guest requests just a tlb flush, don't take the vm lock and
drop the mmu context pointlessly.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

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

Split kvm_arch_vcpu_create() into kvm_arch_vcpu_create() and
kvm_arch_vcpu_setup(), enabling preemption notification between the two.
This mean that we can now do vcpu_load() within kvm_arch_vcpu_setup().
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Moving !user_alloc case to kvm_arch to avoid unnecessary
code logic in non-x86 platform.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Theoretically used to acccess memory known to be ordinary RAM, it was
never implemented.  It is questionable whether it is possible to implement
it correctly.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Improve dirty bit setting for pages that kvm release, until now every page
that we released we marked dirty, from now only pages that have potential
to get dirty we mark dirty.
Signed-off-by: NIzik Eidus <izike@qumranet.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Move out kvm_mmu init and exit functionality from kvm_main.c
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Meanwhile keep the interface in common, and leave as more logic in common
as possible.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Instead of having each architecture do it individually, we
do this in the arch-independent code (just x86 as of now).

[avi: add svm to the mix, which was added to mainline during the
 2.6.24-rc process]
Signed-off-by: NAmit Shah <amit.shah@qumranet.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

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

This is in addition to the current virtual cpu statistics.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Measure the number of times we switch the fpu state.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This is a little more accurate (since it counts actual reloads, not potential
reloads), and reverses the sense of the statistic to measure a bad event like
most of the other stats (e.g. we want to minimize all counters).
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Add two arch hooks to handle kvm_create_vm and kvm destroy_vm. Now, just
put io_bus init and destory in common.
Signed-off-by: NZhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>