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* 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (269 commits)
  KVM: x86: Add missing locking to arch specific vcpu ioctls
  KVM: PPC: Add missing vcpu_load()/vcpu_put() in vcpu ioctls
  KVM: MMU: Segregate shadow pages with different cr0.wp
  KVM: x86: Check LMA bit before set_efer
  KVM: Don't allow lmsw to clear cr0.pe
  KVM: Add cpuid.txt file
  KVM: x86: Tell the guest we'll warn it about tsc stability
  x86, paravirt: don't compute pvclock adjustments if we trust the tsc
  x86: KVM guest: Try using new kvm clock msrs
  KVM: x86: export paravirtual cpuid flags in KVM_GET_SUPPORTED_CPUID
  KVM: x86: add new KVMCLOCK cpuid feature
  KVM: x86: change msr numbers for kvmclock
  x86, paravirt: Add a global synchronization point for pvclock
  x86, paravirt: Enable pvclock flags in vcpu_time_info structure
  KVM: x86: Inject #GP with the right rip on efer writes
  KVM: SVM: Don't allow nested guest to VMMCALL into host
  KVM: x86: Fix exception reinjection forced to true
  KVM: Fix wallclock version writing race
  KVM: MMU: Don't read pdptrs with mmu spinlock held in mmu_alloc_roots
  KVM: VMX: enable VMXON check with SMX enabled (Intel TXT)
  ...
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torvalds committed May 22, 2010
2 parents a825109 + 8fbf065 commit 98edb6c
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Showing 81 changed files with 7,858 additions and 2,843 deletions.
208 changes: 206 additions & 2 deletions Documentation/kvm/api.txt
Original file line number Diff line number Diff line change
Expand Up @@ -656,6 +656,7 @@ struct kvm_clock_data {
4.29 KVM_GET_VCPU_EVENTS

Capability: KVM_CAP_VCPU_EVENTS
Extended by: KVM_CAP_INTR_SHADOW
Architectures: x86
Type: vm ioctl
Parameters: struct kvm_vcpu_event (out)
Expand All @@ -676,7 +677,7 @@ struct kvm_vcpu_events {
__u8 injected;
__u8 nr;
__u8 soft;
__u8 pad;
__u8 shadow;
} interrupt;
struct {
__u8 injected;
Expand All @@ -688,9 +689,13 @@ struct kvm_vcpu_events {
__u32 flags;
};

KVM_VCPUEVENT_VALID_SHADOW may be set in the flags field to signal that
interrupt.shadow contains a valid state. Otherwise, this field is undefined.

4.30 KVM_SET_VCPU_EVENTS

Capability: KVM_CAP_VCPU_EVENTS
Extended by: KVM_CAP_INTR_SHADOW
Architectures: x86
Type: vm ioctl
Parameters: struct kvm_vcpu_event (in)
Expand All @@ -709,6 +714,183 @@ current in-kernel state. The bits are:
KVM_VCPUEVENT_VALID_NMI_PENDING - transfer nmi.pending to the kernel
KVM_VCPUEVENT_VALID_SIPI_VECTOR - transfer sipi_vector

If KVM_CAP_INTR_SHADOW is available, KVM_VCPUEVENT_VALID_SHADOW can be set in
the flags field to signal that interrupt.shadow contains a valid state and
shall be written into the VCPU.

4.32 KVM_GET_DEBUGREGS

Capability: KVM_CAP_DEBUGREGS
Architectures: x86
Type: vm ioctl
Parameters: struct kvm_debugregs (out)
Returns: 0 on success, -1 on error

Reads debug registers from the vcpu.

struct kvm_debugregs {
__u64 db[4];
__u64 dr6;
__u64 dr7;
__u64 flags;
__u64 reserved[9];
};

4.33 KVM_SET_DEBUGREGS

Capability: KVM_CAP_DEBUGREGS
Architectures: x86
Type: vm ioctl
Parameters: struct kvm_debugregs (in)
Returns: 0 on success, -1 on error

Writes debug registers into the vcpu.

See KVM_GET_DEBUGREGS for the data structure. The flags field is unused
yet and must be cleared on entry.

4.34 KVM_SET_USER_MEMORY_REGION

Capability: KVM_CAP_USER_MEM
Architectures: all
Type: vm ioctl
Parameters: struct kvm_userspace_memory_region (in)
Returns: 0 on success, -1 on error

struct kvm_userspace_memory_region {
__u32 slot;
__u32 flags;
__u64 guest_phys_addr;
__u64 memory_size; /* bytes */
__u64 userspace_addr; /* start of the userspace allocated memory */
};

/* for kvm_memory_region::flags */
#define KVM_MEM_LOG_DIRTY_PAGES 1UL

This ioctl allows the user to create or modify a guest physical memory
slot. When changing an existing slot, it may be moved in the guest
physical memory space, or its flags may be modified. It may not be
resized. Slots may not overlap in guest physical address space.

Memory for the region is taken starting at the address denoted by the
field userspace_addr, which must point at user addressable memory for
the entire memory slot size. Any object may back this memory, including
anonymous memory, ordinary files, and hugetlbfs.

It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr
be identical. This allows large pages in the guest to be backed by large
pages in the host.

The flags field supports just one flag, KVM_MEM_LOG_DIRTY_PAGES, which
instructs kvm to keep track of writes to memory within the slot. See
the KVM_GET_DIRTY_LOG ioctl.

When the KVM_CAP_SYNC_MMU capability, changes in the backing of the memory
region are automatically reflected into the guest. For example, an mmap()
that affects the region will be made visible immediately. Another example
is madvise(MADV_DROP).

It is recommended to use this API instead of the KVM_SET_MEMORY_REGION ioctl.
The KVM_SET_MEMORY_REGION does not allow fine grained control over memory
allocation and is deprecated.

4.35 KVM_SET_TSS_ADDR

Capability: KVM_CAP_SET_TSS_ADDR
Architectures: x86
Type: vm ioctl
Parameters: unsigned long tss_address (in)
Returns: 0 on success, -1 on error

This ioctl defines the physical address of a three-page region in the guest
physical address space. The region must be within the first 4GB of the
guest physical address space and must not conflict with any memory slot
or any mmio address. The guest may malfunction if it accesses this memory
region.

This ioctl is required on Intel-based hosts. This is needed on Intel hardware
because of a quirk in the virtualization implementation (see the internals
documentation when it pops into existence).

4.36 KVM_ENABLE_CAP

Capability: KVM_CAP_ENABLE_CAP
Architectures: ppc
Type: vcpu ioctl
Parameters: struct kvm_enable_cap (in)
Returns: 0 on success; -1 on error

+Not all extensions are enabled by default. Using this ioctl the application
can enable an extension, making it available to the guest.

On systems that do not support this ioctl, it always fails. On systems that
do support it, it only works for extensions that are supported for enablement.

To check if a capability can be enabled, the KVM_CHECK_EXTENSION ioctl should
be used.

struct kvm_enable_cap {
/* in */
__u32 cap;

The capability that is supposed to get enabled.

__u32 flags;

A bitfield indicating future enhancements. Has to be 0 for now.

__u64 args[4];

Arguments for enabling a feature. If a feature needs initial values to
function properly, this is the place to put them.

__u8 pad[64];
};

4.37 KVM_GET_MP_STATE

Capability: KVM_CAP_MP_STATE
Architectures: x86, ia64
Type: vcpu ioctl
Parameters: struct kvm_mp_state (out)
Returns: 0 on success; -1 on error

struct kvm_mp_state {
__u32 mp_state;
};

Returns the vcpu's current "multiprocessing state" (though also valid on
uniprocessor guests).

Possible values are:

- KVM_MP_STATE_RUNNABLE: the vcpu is currently running
- KVM_MP_STATE_UNINITIALIZED: the vcpu is an application processor (AP)
which has not yet received an INIT signal
- KVM_MP_STATE_INIT_RECEIVED: the vcpu has received an INIT signal, and is
now ready for a SIPI
- KVM_MP_STATE_HALTED: the vcpu has executed a HLT instruction and
is waiting for an interrupt
- KVM_MP_STATE_SIPI_RECEIVED: the vcpu has just received a SIPI (vector
accesible via KVM_GET_VCPU_EVENTS)

This ioctl is only useful after KVM_CREATE_IRQCHIP. Without an in-kernel
irqchip, the multiprocessing state must be maintained by userspace.

4.38 KVM_SET_MP_STATE

Capability: KVM_CAP_MP_STATE
Architectures: x86, ia64
Type: vcpu ioctl
Parameters: struct kvm_mp_state (in)
Returns: 0 on success; -1 on error

Sets the vcpu's current "multiprocessing state"; see KVM_GET_MP_STATE for
arguments.

This ioctl is only useful after KVM_CREATE_IRQCHIP. Without an in-kernel
irqchip, the multiprocessing state must be maintained by userspace.

5. The kvm_run structure

Expand Down Expand Up @@ -820,6 +1002,13 @@ executed a memory-mapped I/O instruction which could not be satisfied
by kvm. The 'data' member contains the written data if 'is_write' is
true, and should be filled by application code otherwise.

NOTE: For KVM_EXIT_IO, KVM_EXIT_MMIO and KVM_EXIT_OSI, the corresponding
operations are complete (and guest state is consistent) only after userspace
has re-entered the kernel with KVM_RUN. The kernel side will first finish
incomplete operations and then check for pending signals. Userspace
can re-enter the guest with an unmasked signal pending to complete
pending operations.

/* KVM_EXIT_HYPERCALL */
struct {
__u64 nr;
Expand All @@ -829,7 +1018,9 @@ true, and should be filled by application code otherwise.
__u32 pad;
} hypercall;

Unused.
Unused. This was once used for 'hypercall to userspace'. To implement
such functionality, use KVM_EXIT_IO (x86) or KVM_EXIT_MMIO (all except s390).
Note KVM_EXIT_IO is significantly faster than KVM_EXIT_MMIO.

/* KVM_EXIT_TPR_ACCESS */
struct {
Expand Down Expand Up @@ -870,6 +1061,19 @@ s390 specific.

powerpc specific.

/* KVM_EXIT_OSI */
struct {
__u64 gprs[32];
} osi;

MOL uses a special hypercall interface it calls 'OSI'. To enable it, we catch
hypercalls and exit with this exit struct that contains all the guest gprs.

If exit_reason is KVM_EXIT_OSI, then the vcpu has triggered such a hypercall.
Userspace can now handle the hypercall and when it's done modify the gprs as
necessary. Upon guest entry all guest GPRs will then be replaced by the values
in this struct.

/* Fix the size of the union. */
char padding[256];
};
Expand Down
42 changes: 42 additions & 0 deletions Documentation/kvm/cpuid.txt
Original file line number Diff line number Diff line change
@@ -0,0 +1,42 @@
KVM CPUID bits
Glauber Costa <glommer@redhat.com>, Red Hat Inc, 2010
=====================================================

A guest running on a kvm host, can check some of its features using
cpuid. This is not always guaranteed to work, since userspace can
mask-out some, or even all KVM-related cpuid features before launching
a guest.

KVM cpuid functions are:

function: KVM_CPUID_SIGNATURE (0x40000000)
returns : eax = 0,
ebx = 0x4b4d564b,
ecx = 0x564b4d56,
edx = 0x4d.
Note that this value in ebx, ecx and edx corresponds to the string "KVMKVMKVM".
This function queries the presence of KVM cpuid leafs.


function: define KVM_CPUID_FEATURES (0x40000001)
returns : ebx, ecx, edx = 0
eax = and OR'ed group of (1 << flag), where each flags is:


flag || value || meaning
=============================================================================
KVM_FEATURE_CLOCKSOURCE || 0 || kvmclock available at msrs
|| || 0x11 and 0x12.
------------------------------------------------------------------------------
KVM_FEATURE_NOP_IO_DELAY || 1 || not necessary to perform delays
|| || on PIO operations.
------------------------------------------------------------------------------
KVM_FEATURE_MMU_OP || 2 || deprecated.
------------------------------------------------------------------------------
KVM_FEATURE_CLOCKSOURCE2 || 3 || kvmclock available at msrs
|| || 0x4b564d00 and 0x4b564d01
------------------------------------------------------------------------------
KVM_FEATURE_CLOCKSOURCE_STABLE_BIT || 24 || host will warn if no guest-side
|| || per-cpu warps are expected in
|| || kvmclock.
------------------------------------------------------------------------------
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