linux-stable.git/tools/testing/selftests/kvm/include, branch linux-5.0.y

KVM: selftests: complete IO before migrating guest state

2019-05-04T07:21:21+00:00

[ Upstream commit 0f73bbc851ed32d22bbd86be09e0365c460bcd2e ]

Documentation/virtual/kvm/api.txt states:

  NOTE: For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXIT_OSI, KVM_EXIT_PAPR and
        KVM_EXIT_EPR 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.

Because guest state may be inconsistent, starting state migration after
an IO exit without first completing IO may result in test failures, e.g.
a proposed change to KVM's handling of %rip in its fast PIO handling[1]
will cause the new VM, i.e. the post-migration VM, to have its %rip set
to the IN instruction that triggered KVM_EXIT_IO, leading to a test
assertion due to a stage mismatch.

For simplicitly, require KVM_CAP_IMMEDIATE_EXIT to complete IO and skip
the test if it's not available.  The addition of KVM_CAP_IMMEDIATE_EXIT
predates the state selftest by more than a year.

[1] https://patchwork.kernel.org/patch/10848545/

Fixes: fa3899add1056 ("kvm: selftests: add basic test for state save and restore")
Reported-by: Jim Mattson 
Signed-off-by: Sean Christopherson 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Sasha Levin (Microsoft)

kvm: selftests: aarch64: dirty_log_test: support greater than 40-bit IPAs

2018-12-21T10:28:30+00:00

When KVM has KVM_CAP_ARM_VM_IPA_SIZE we can test with > 40-bit IPAs by
using the 'type' field of KVM_CREATE_VM.

Signed-off-by: Andrew Jones 
Signed-off-by: Radim Krčmář

kvm: selftests: add pa-48/va-48 VM modes

2018-12-21T10:28:30+00:00

Signed-off-by: Andrew Jones 
Signed-off-by: Radim Krčmář

KVM: selftests: implement an unchecked version of vcpu_ioctl()

2018-12-14T16:59:55+00:00

In case we want to test failing ioctls we need an option to not
fail. Following _vcpu_run() precedent implement _vcpu_ioctl().

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Paolo Bonzini

kvm: introduce manual dirty log reprotect

2018-12-14T11:34:19+00:00

There are two problems with KVM_GET_DIRTY_LOG.  First, and less important,
it can take kvm->mmu_lock for an extended period of time.  Second, its user
can actually see many false positives in some cases.  The latter is due
to a benign race like this:

  1. KVM_GET_DIRTY_LOG returns a set of dirty pages and write protects
     them.
  2. The guest modifies the pages, causing them to be marked ditry.
  3. Userspace actually copies the pages.
  4. KVM_GET_DIRTY_LOG returns those pages as dirty again, even though
     they were not written to since (3).

This is especially a problem for large guests, where the time between
(1) and (3) can be substantial.  This patch introduces a new
capability which, when enabled, makes KVM_GET_DIRTY_LOG not
write-protect the pages it returns.  Instead, userspace has to
explicitly clear the dirty log bits just before using the content
of the page.  The new KVM_CLEAR_DIRTY_LOG ioctl can also operate on a
64-page granularity rather than requiring to sync a full memslot;
this way, the mmu_lock is taken for small amounts of time, and
only a small amount of time will pass between write protection
of pages and the sending of their content.

Signed-off-by: Paolo Bonzini

KVM: selftests: add Enlightened VMCS test

2018-10-16T22:30:21+00:00

Modify test library and add eVMCS test. This includes nVMX save/restore
testing.

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Paolo Bonzini

KVM: selftests: state_test: test bare VMXON migration

2018-10-16T22:30:18+00:00

Split prepare_for_vmx_operation() into prepare_for_vmx_operation() and
load_vmcs() so we can inject GUEST_SYNC() in between.

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Paolo Bonzini

kvm: selftests: stop lying to aarch64 tests about PA-bits

2018-10-16T22:29:38+00:00

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: Andrew Jones 
Signed-off-by: Paolo Bonzini

kvm: selftests: introduce new VM mode for 64K pages

2018-10-16T22:29:35+00:00

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: Andrew Jones 
Signed-off-by: Paolo Bonzini

kvm: selftests: add vcpu support for aarch64

2018-10-16T22:26:56+00:00

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: Andrew Jones 
Signed-off-by: Paolo Bonzini