Commit Graph

200 Commits

Author SHA1 Message Date
Sean Christopherson
751f280017 KVM: selftests: Drop reserved bit checks from PTE accessor
Drop the reserved bit checks from the helper to retrieve a PTE, there's
very little value in sanity checking the constructed page tables as any
will quickly be noticed in the form of an unexpected #PF.  The checks
also place unnecessary restrictions on the usage of the helpers, e.g. if
a test _wanted_ to set reserved bits for whatever reason.

Removing the NX check in particular allows for the removal of the @vcpu
param, which will in turn allow the helper to be reused nearly verbatim
for addr_gva2gpa().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-3-seanjc@google.com
2022-11-16 16:58:54 -08:00
Sean Christopherson
816c54b747 KVM: selftests: Drop helpers to read/write page table entries
Drop vm_{g,s}et_page_table_entry() and instead expose the "inner"
helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the
PTE, i.e. let tests directly modify PTEs instead of bouncing through
helpers that just make life difficult.

Opportunsitically use BIT_ULL() in emulator_error_test, and use the
MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the
same value.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-2-seanjc@google.com
2022-11-16 16:58:54 -08:00
Peter Gonda
426729b2cf KVM: selftests: Add ucall pool based implementation
To play nice with guests whose stack memory is encrypted, e.g. AMD SEV,
introduce a new "ucall pool" implementation that passes the ucall struct
via dedicated memory (which can be mapped shared, a.k.a. as plain text).

Because not all architectures have access to the vCPU index in the guest,
use a bitmap with atomic accesses to track which entries in the pool are
free/used.  A list+lock could also work in theory, but synchronizing the
individual pointers to the guest would be a mess.

Note, there's no need to rewalk the bitmap to ensure success.  If all
vCPUs are simply allocating, success is guaranteed because there are
enough entries for all vCPUs.  If one or more vCPUs are freeing and then
reallocating, success is guaranteed because vCPUs _always_ walk the
bitmap from 0=>N; if vCPU frees an entry and then wins a race to
re-allocate, then either it will consume the entry it just freed (bit is
the first free bit), or the losing vCPU is guaranteed to see the freed
bit (winner consumes an earlier bit, which the loser hasn't yet visited).

Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Peter Gonda <pgonda@google.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006003409.649993-8-seanjc@google.com
2022-11-16 16:58:53 -08:00
Sean Christopherson
28a65567ac KVM: selftests: Drop now-unnecessary ucall_uninit()
Drop ucall_uninit() and ucall_arch_uninit() now that ARM doesn't modify
the host's copy of ucall_exit_mmio_addr, i.e. now that there's no need to
reset the pointer before potentially creating a new VM.  The few calls to
ucall_uninit() are all immediately followed by kvm_vm_free(), and that is
likely always going to hold true, i.e. it's extremely unlikely a test
will want to effectively disable ucall in the middle of a test.

Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Tested-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006003409.649993-7-seanjc@google.com
2022-11-16 16:58:53 -08:00
Sean Christopherson
dc88244bf5 KVM: selftests: Automatically do init_ucall() for non-barebones VMs
Do init_ucall() automatically during VM creation to kill two (three?)
birds with one stone.

First, initializing ucall immediately after VM creations allows forcing
aarch64's MMIO ucall address to immediately follow memslot0.  This is
still somewhat fragile as tests could clobber the MMIO address with a
new memslot, but it's safe-ish since tests have to be conversative when
accounting for memslot0.  And this can be hardened in the future by
creating a read-only memslot for the MMIO page (KVM ARM exits with MMIO
if the guest writes to a read-only memslot).  Add a TODO to document that
selftests can and should use a memslot for the ucall MMIO (doing so
requires yet more rework because tests assumes thay can use all memslots
except memslot0).

Second, initializing ucall for all VMs prepares for making ucall
initialization meaningful on all architectures.  aarch64 is currently the
only arch that needs to do any setup, but that will change in the future
by switching to a pool-based implementation (instead of the current
stack-based approach).

Lastly, defining the ucall MMIO address from common code will simplify
switching all architectures (except s390) to a common MMIO-based ucall
implementation (if there's ever sufficient motivation to do so).

Cc: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Tested-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006003409.649993-4-seanjc@google.com
2022-11-16 16:58:51 -08:00
Sean Christopherson
ef38871eb2 KVM: selftests: Consolidate boilerplate code in get_ucall()
Consolidate the actual copying of a ucall struct from guest=>host into
the common get_ucall().  Return a host virtual address instead of a guest
virtual address even though the addr_gva2hva() part could be moved to
get_ucall() too.  Conceptually, get_ucall() is invoked from the host and
should return a host virtual address (and returning NULL for "nothing to
see here" is far superior to returning 0).

Use pointer shenanigans instead of an unnecessary bounce buffer when the
caller of get_ucall() provides a valid pointer.

Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Tested-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006003409.649993-3-seanjc@google.com
2022-11-16 16:58:51 -08:00
Sean Christopherson
7046638192 KVM: selftests: Consolidate common code for populating ucall struct
Make ucall() a common helper that populates struct ucall, and only calls
into arch code to make the actually call out to userspace.

Rename all arch-specific helpers to make it clear they're arch-specific,
and to avoid collisions with common helpers (one more on its way...)

Add WRITE_ONCE() to stores in ucall() code (as already done to aarch64
code in commit 9e2f6498ef ("selftests: KVM: Handle compiler
optimizations in ucall")) to prevent clang optimizations breaking ucalls.

Cc: Colton Lewis <coltonlewis@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Tested-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006003409.649993-2-seanjc@google.com
2022-11-16 16:58:51 -08:00
David Matlack
7812d80c0f KVM: selftests: Rename perf_test_util symbols to memstress
Replace the perf_test_ prefix on symbol names with memstress_ to match
the new file name.

"memstress" better describes the functionality proveded by this library,
which is to provide functionality for creating and running a VM that
stresses VM memory by reading and writing to guest memory on all vCPUs
in parallel.

"memstress" also contains the same number of chracters as "perf_test",
making it a drop-in replacement in symbols, e.g. function names, without
impacting line lengths. Also the lack of underscore between "mem" and
"stress" makes it clear "memstress" is a noun.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221012165729.3505266-4-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-11-16 10:58:32 -08:00
David Matlack
9fda6753c9 KVM: selftests: Rename perf_test_util.[ch] to memstress.[ch]
Rename the perf_test_util.[ch] files to memstress.[ch]. Symbols are
renamed in the following commit to reduce the amount of churn here in
hopes of playiing nice with git's file rename detection.

The name "memstress" was chosen to better describe the functionality
proveded by this library, which is to create and run a VM that
reads/writes to guest memory on all vCPUs in parallel.

"memstress" also contains the same number of chracters as "perf_test",
making it a drop-in replacement in symbols, e.g. function names, without
impacting line lengths. Also the lack of underscore between "mem" and
"stress" makes it clear "memstress" is a noun.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221012165729.3505266-2-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-11-16 10:57:34 -08:00
Ricardo Koller
1446e33143 KVM: selftests: Use the right memslot for code, page-tables, and data allocations
Now that kvm_vm allows specifying different memslots for code, page tables,
and data, use the appropriate memslot when making allocations in
common/libraty code. Change them accordingly:

- code (allocated by lib/elf) use the CODE memslot
- stacks, exception tables, and other core data pages (like the TSS in x86)
  use the DATA memslot
- page tables and the PGD use the PT memslot
- test data (anything allocated with vm_vaddr_alloc()) uses the TEST_DATA
  memslot

No functional change intended. All allocators keep using memslot #0.

Cc: Sean Christopherson <seanjc@google.com>
Cc: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221017195834.2295901-10-ricarkol@google.com
2022-11-10 19:10:27 +00:00
David Matlack
458e98746f KVM: selftests: Fix nx_huge_pages_test on TDP-disabled hosts
Map the test's huge page region with 2MiB virtual mappings when TDP is
disabled so that KVM can shadow the region with huge pages. This fixes
nx_huge_pages_test on hosts where TDP hardware support is disabled.

Purposely do not skip this test on TDP-disabled hosts. While we don't
care about NX Huge Pages on TDP-disabled hosts from a security
perspective, KVM does support it, and so we should test it.

For TDP-enabled hosts, continue mapping the region with 4KiB pages to
ensure that KVM can map it with huge pages irrespective of the guest
mappings.

Fixes: 8448ec5993 ("KVM: selftests: Add NX huge pages test")
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220929181207.2281449-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-30 06:39:36 -04:00
David Matlack
4d2bd14319 KVM: selftests: Add helpers to read kvm_{intel,amd} boolean module parameters
Add helper functions for reading the value of kvm_intel and kvm_amd
boolean module parameters. Use the kvm_intel variant in
vm_is_unrestricted_guest() to simplify the check for
kvm_intel.unrestricted_guest.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220929181207.2281449-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-30 06:39:36 -04:00
Sean Christopherson
c96409d1e5 Revert "KVM: selftests: Fix nested SVM tests when built with clang"
Revert back to using memset() in generic_svm_setup() now that KVM
selftests override memset() and friends specifically to prevent the
compiler from generating fancy code and/or linking to the libc
implementation.

This reverts commit ed290e1c20.

Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220928233652.783504-8-seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-30 06:39:34 -04:00
David Matlack
0f816e024f KVM: selftests: Skip tests that require EPT when it is not available
Skip selftests that require EPT support in the VM when it is not
available. For example, if running on a machine where kvm_intel.ept=N
since KVM does not offer EPT support to guests if EPT is not supported
on the host.

This commit causes vmx_dirty_log_test to be skipped instead of failing
on hosts where kvm_intel.ept=N.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220926171457.532542-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-27 07:58:03 -04:00
Andrei Vagin
281106f938 selftests: kvm: set rax before vmcall
kvm_hypercall has to place the hypercall number in rax.

Trace events show that kvm_pv_test doesn't work properly:
     kvm_pv_test-53132: kvm_hypercall: nr 0x0 a0 0x0 a1 0x0 a2 0x0 a3 0x0
     kvm_pv_test-53132: kvm_hypercall: nr 0x0 a0 0x0 a1 0x0 a2 0x0 a3 0x0
     kvm_pv_test-53132: kvm_hypercall: nr 0x0 a0 0x0 a1 0x0 a2 0x0 a3 0x0

With this change, it starts working as expected:
     kvm_pv_test-54285: kvm_hypercall: nr 0x5 a0 0x0 a1 0x0 a2 0x0 a3 0x0
     kvm_pv_test-54285: kvm_hypercall: nr 0xa a0 0x0 a1 0x0 a2 0x0 a3 0x0
     kvm_pv_test-54285: kvm_hypercall: nr 0xb a0 0x0 a1 0x0 a2 0x0 a3 0x0

Signed-off-by: Andrei Vagin <avagin@google.com>
Message-Id: <20220722230241.1944655-5-avagin@google.com>
Fixes: ac4a4d6de2 ("selftests: kvm: test enforcement of paravirtual cpuid features")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-08-01 08:43:05 -04:00
Sean Christopherson
12a985aeb4 KVM: selftests: Use the common cpuid() helper in cpu_vendor_string_is()
Use cpuid() to get CPUID.0x0 in cpu_vendor_string_is(), thus eliminating
the last open coded usage of CPUID (ignoring debug_regs.c, which emits
CPUID from the guest to trigger a VM-Exit and doesn't actually care about
the results of CPUID).

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-42-seanjc@google.com
2022-07-13 18:14:25 -07:00
Sean Christopherson
090cd45b21 KVM: selftests: Clean up requirements for XFD-aware XSAVE features
Provide informative error messages for the various checks related to
requesting access to XSAVE features that are buried behind XSAVE Feature
Disabling (XFD).

Opportunistically rename the helper to have "require" in the name so that
it's somewhat obvious that the helper may skip the test.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-41-seanjc@google.com
2022-07-13 18:14:24 -07:00
Sean Christopherson
d4c94ee812 KVM: selftests: Skip AMX test if ARCH_REQ_XCOMP_GUEST_PERM isn't supported
Skip the AMX test instead of silently returning if the host kernel
doesn't support ARCH_REQ_XCOMP_GUEST_PERM.  KVM didn't support XFD until
v5.17, so it's extremely unlikely allowing the test to run on a pre-v5.15
kernel is the right thing to do.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-40-seanjc@google.com
2022-07-13 18:14:24 -07:00
Sean Christopherson
7fbb653e01 KVM: selftests: Check KVM's supported CPUID, not host CPUID, for XFD
Use kvm_cpu_has() to check for XFD supported in vm_xsave_req_perm(),
simply checking host CPUID doesn't guarantee KVM supports AMX/XFD.

Opportunistically hoist the check above the bit check; if XFD isn't
supported, it's far better to get a "not supported at all" message, as
opposed to a "feature X isn't supported" message".

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-39-seanjc@google.com
2022-07-13 18:14:24 -07:00
Sean Christopherson
d04019274d KVM: selftests: Inline "get max CPUID leaf" helpers
Make the "get max CPUID leaf" helpers static inline, there's no reason to
bury the one liners in processor.c.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-38-seanjc@google.com
2022-07-13 18:14:23 -07:00
Sean Christopherson
8fe09d6a91 KVM: selftests: Set input function/index in raw CPUID helper(s)
Set the function/index for CPUID in the helper instead of relying on the
caller to do so.  In addition to reducing the risk of consuming an
uninitialized ECX, having the function/index embedded in the call makes
it easier to understand what is being checked.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-32-seanjc@google.com
2022-07-13 18:14:21 -07:00
Sean Christopherson
813e38cd6d KVM: selftests: Make get_supported_cpuid() returns "const"
Tag the returned CPUID pointers from kvm_get_supported_cpuid(),
kvm_get_supported_hv_cpuid(), and vcpu_get_supported_hv_cpuid() "const"
to prevent reintroducing the broken pattern of modifying the static
"cpuid" variable used by kvm_get_supported_cpuid() to cache the results
of KVM_GET_SUPPORTED_CPUID.

Update downstream consumers as needed.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-31-seanjc@google.com
2022-07-13 18:14:20 -07:00
Sean Christopherson
4dcd130c9b KVM: selftests: Use vCPU's CPUID directly in Hyper-V test
Use the vCPU's persistent CPUID array directly when manipulating the set
of exposed Hyper-V CPUID features.  Drop set_cpuid() to route all future
modification through the vCPU helpers; the Hyper-V features test was the
last user.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-27-seanjc@google.com
2022-07-13 18:14:18 -07:00
Sean Christopherson
3a5d36b32b KVM: selftests: Use vcpu_get_cpuid_entry() in PV features test (sort of)
Add a new helper, vcpu_clear_cpuid_entry(), to do a RMW operation on the
vCPU's CPUID model to clear a given CPUID entry, and use it to clear
KVM's paravirt feature instead of operating on kvm_get_supported_cpuid()'s
static "cpuid" variable.  This also eliminates a user of
the soon-be-defunct set_cpuid() helper.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-26-seanjc@google.com
2022-07-13 18:14:18 -07:00
Sean Christopherson
1940af0b81 KVM: selftests: Add and use helper to set vCPU's CPUID maxphyaddr
Add a helper to set a vCPU's guest.MAXPHYADDR, and use it in the test
that verifies the emulator returns an error on an unknown instruction
when KVM emulates in response to an EPT violation with a GPA that is
legal in hardware but illegal with respect to the guest's MAXPHYADDR.

Add a helper even though there's only a single user at this time.  Before
its removal, mmu_role_test also stuffed guest.MAXPHYADDR, and the helper
provides a small amount of clarity.

More importantly, this eliminates a set_cpuid() user and an instance of
modifying kvm_get_supported_cpuid()'s static "cpuid".

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-25-seanjc@google.com
2022-07-13 18:14:17 -07:00
Sean Christopherson
7af7161d87 KVM: selftests: Use vm->pa_bits to generate reserved PA bits
Use vm->pa_bits to generate the mask of physical address bits that are
reserved in page table entries.  vm->pa_bits is set when the VM is
created, i.e. it's guaranteed to be valid when populating page tables.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-24-seanjc@google.com
2022-07-13 18:14:17 -07:00
Sean Christopherson
c41880b5f0 KVM: selftests: Add helpers to get and modify a vCPU's CPUID entries
Add helpers to get a specific CPUID entry for a given vCPU, and to toggle
a specific CPUID-based feature for a vCPU.  The helpers will reduce the
amount of boilerplate code needed to tweak a vCPU's CPUID model, improve
code clarity, and most importantly move tests away from modifying the
static "cpuid" returned by kvm_get_supported_cpuid().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-23-seanjc@google.com
2022-07-13 18:14:16 -07:00
Sean Christopherson
662162fed2 KVM: selftests: Use get_cpuid_entry() in kvm_get_supported_cpuid_index()
Use get_cpuid_entry() in kvm_get_supported_cpuid_index() to replace
functionally identical code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-22-seanjc@google.com
2022-07-13 18:14:16 -07:00
Sean Christopherson
8b02674103 KVM: selftests: Rename and tweak get_cpuid() to get_cpuid_entry()
Rename get_cpuid() to get_cpuid_entry() to better reflect its behavior.
Leave set_cpuid() as is to avoid unnecessary churn, that helper will soon
be removed entirely.

Oppurtunistically tweak the implementation to avoid using a temporary
variable in anticipation of taggin the input @cpuid with "const".

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-21-seanjc@google.com
2022-07-13 18:14:15 -07:00
Sean Christopherson
d838b313aa KVM: selftests: Don't use a static local in vcpu_get_supported_hv_cpuid()
Don't use a static variable for the Hyper-V supported CPUID array, the
helper unconditionally reallocates the array on every invocation (and all
callers free the array immediately after use).  The array is intentionally
recreated and refilled because the set of supported CPUID features is
dependent on vCPU state, e.g. whether or not eVMCS has been enabled.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-20-seanjc@google.com
2022-07-13 18:14:15 -07:00
Sean Christopherson
7fbc6038ac KVM: selftests: Cache CPUID in struct kvm_vcpu
Cache a vCPU's CPUID information in "struct kvm_vcpu" to allow fixing the
mess where tests, often unknowingly, modify the global/static "cpuid"
allocated by kvm_get_supported_cpuid().

Add vcpu_init_cpuid() to handle stuffing an entirely different CPUID
model, e.g. during vCPU creation or when switching to the Hyper-V enabled
CPUID model.  Automatically refresh the cache on vcpu_set_cpuid() so that
any adjustments made by KVM are always reflected in the cache.  Drop
vcpu_get_cpuid() entirely to force tests to use the cache, and to allow
adding e.g. vcpu_get_cpuid_entry() in the future without creating a
conflicting set of APIs where vcpu_get_cpuid() does KVM_GET_CPUID2, but
vcpu_get_cpuid_entry() does not.

Opportunistically convert the VMX nested state test and KVM PV test to
manipulating the vCPU's CPUID (because it's easy), but use
vcpu_init_cpuid() for the Hyper-V features test and "emulator error" test
to effectively retain their current behavior as they're less trivial to
convert.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-19-seanjc@google.com
2022-07-13 18:14:15 -07:00
Sean Christopherson
fc66963d7b KVM: selftests: Split out kvm_cpuid2_size() from allocate_kvm_cpuid2()
Split out the computation of the effective size of a kvm_cpuid2 struct
from allocate_kvm_cpuid2(), and modify both to take an arbitrary number
of entries.  Future commits will add caching of a vCPU's CPUID model, and
will (a) be able to precisely size the entries array, and (b) will need
to know the effective size of the struct in order to copy to/from the
cache.

Expose the helpers so that the Hyper-V Features test can use them in the
(somewhat distant) future.  The Hyper-V test very, very subtly relies on
propagating CPUID info across vCPU instances, and will need to make a
copy of the previous vCPU's CPUID information when it switches to using
the per-vCPU cache.  Alternatively, KVM could provide helpers to
duplicate and/or copy a kvm_cpuid2 instance, but each is literally a
single line of code if the helpers are exposed, and it's not like the
size of kvm_cpuid2 is secret knowledge.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-18-seanjc@google.com
2022-07-13 18:14:14 -07:00
Sean Christopherson
1ecbb337fa KVM: selftests: Use kvm_cpu_has() for nested VMX checks
Use kvm_cpu_has() to check for nested VMX support, and drop the helpers
now that their functionality is trivial to implement.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-7-seanjc@google.com
2022-07-13 18:14:10 -07:00
Sean Christopherson
f21940a3bb KVM: selftests: Use kvm_cpu_has() for nested SVM checks
Use kvm_cpu_has() to check for nested SVM support, and drop the helpers
now that their functionality is trivial to implement.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-6-seanjc@google.com
2022-07-13 18:14:10 -07:00
Sean Christopherson
61d76b8a69 KVM: selftests: Add framework to query KVM CPUID bits
Add X86_FEATURE_* magic in the style of KVM-Unit-Tests' implementation,
where the CPUID function, index, output register, and output bit position
are embedded in the macro value.  Add kvm_cpu_has() to query KVM's
supported CPUID and use it set_sregs_test, which is the most prolific
user of manual feature querying.

Opportunstically rename calc_cr4_feature_bits() to
calc_supported_cr4_feature_bits() to better capture how the CR4 bits are
chosen.

Link: https://lore.kernel.org/all/20210422005626.564163-1-ricarkol@google.com
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-4-seanjc@google.com
2022-07-13 18:14:09 -07:00
Sean Christopherson
4c16fa3ee9 KVM: selftests: Set KVM's supported CPUID as vCPU's CPUID during recreate
On x86-64, set KVM's supported CPUID as the vCPU's CPUID when recreating
a VM+vCPU to deduplicate code for state save/restore tests, and to
provide symmetry of sorts with respect to vm_create_with_one_vcpu().  The
extra KVM_SET_CPUID2 call is wasteful for Hyper-V, but ultimately is
nothing more than an expensive nop, and overriding the vCPU's CPUID with
the Hyper-V CPUID information is the only known scenario where a state
save/restore test wouldn't need/want the default CPUID.

Opportunistically use __weak for the default vm_compute_max_gfn(), it's
provided by tools' compiler.h.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-2-seanjc@google.com
2022-07-13 18:14:08 -07:00
Sean Christopherson
3b23054cd3 KVM: selftests: Add x86-64 support for exception fixup
Add x86-64 support for exception fixup on single instructions, without
forcing tests to install their own fault handlers.  Use registers r9-r11
to flag the instruction as "safe" and pass fixup/vector information,
i.e. introduce yet another flavor of fixup (versus the kernel's in-memory
tables and KUT's per-CPU area) to take advantage of KVM sefltests being
64-bit only.

Using only registers avoids the need to allocate fixup tables, ensure
FS or GS base is valid for the guest, ensure memory is mapped into the
guest, etc..., and also reduces the potential for recursive faults due to
accessing memory.

Providing exception fixup trivializes tests that just want to verify that
an instruction faults, e.g. no need to track start/end using global
labels, no need to install a dedicated handler, etc...

Deliberately do not support #DE in exception fixup so that the fixup glue
doesn't need to account for a fault with vector == 0, i.e. the vector can
also indicate that a fault occurred.  KVM injects #DE only for esoteric
emulation scenarios, i.e. there's very, very little value in testing #DE.
Force any test that wants to generate #DEs to install its own handler(s).

Use kvm_pv_test as a guinea pig for the new fixup, as it has a very
straightforward use case of wanting to verify that RDMSR and WRMSR fault.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220608224516.3788274-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-20 11:50:57 -04:00
Sean Christopherson
9393cb13fa KVM: selftests: Use kvm_has_cap(), not kvm_check_cap(), where possible
Replace calls to kvm_check_cap() that treat its return as a boolean with
calls to kvm_has_cap().  Several instances of kvm_check_cap() were missed
when kvm_has_cap() was introduced.

Reported-by: Andrew Jones <drjones@redhat.com>
Fixes: 3ea9b80965 ("KVM: selftests: Add kvm_has_cap() to provide syntactic sugar")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220613161942.1586791-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-14 12:44:47 -04:00
Sean Christopherson
fcba483e82 KVM: selftests: Sanity check input to ioctls() at build time
Add a static assert to the KVM/VM/vCPU ioctl() helpers to verify that the
size of the argument provided matches the expected size of the IOCTL.
Because ioctl() ultimately takes a "void *", it's all too easy to pass in
garbage and not detect the error until runtime.  E.g. while working on a
CPUID rework, selftests happily compiled when vcpu_set_cpuid()
unintentionally passed the cpuid() function as the parameter to ioctl()
(a local "cpuid" parameter was removed, but its use was not replaced with
"vcpu->cpuid" as intended).

Tweak a variety of benign issues that aren't compatible with the sanity
check, e.g. passing a non-pointer for ioctls().

Note, static_assert() requires a string on older versions of GCC.  Feed
it an empty string to make the compiler happy.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:48:09 -04:00
Sean Christopherson
7ed397d107 KVM: selftests: Add TEST_REQUIRE macros to reduce skipping copy+paste
Add TEST_REQUIRE() and __TEST_REQUIRE() to replace the myriad open coded
instances of selftests exiting with KSFT_SKIP after printing an
informational message.  In addition to reducing the amount of boilerplate
code in selftests, the UPPERCASE macro names make it easier to visually
identify a test's requirements.

Convert usage that erroneously uses something other than print_skip()
and/or "exits" with '0' or some other non-KSFT_SKIP value.

Intentionally drop a kvm_vm_free() in aarch64/debug-exceptions.c as part
of the conversion.  All memory and file descriptors are freed on process
exit, so the explicit free is superfluous.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:29 -04:00
Sean Christopherson
768e9a6185 KVM: selftests: Purge vm+vcpu_id == vcpu silliness
Take a vCPU directly instead of a VM+vcpu pair in all vCPU-scoped helpers
and ioctls.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:22 -04:00
Sean Christopherson
df84cef531 KVM: selftests: Stop conflating vCPU index and ID in perf tests
Track vCPUs by their 'struct kvm_vcpu' object, and stop assuming that a
vCPU's ID is the same as its index when referencing a vCPU's metadata.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:20 -04:00
Sean Christopherson
f742d94ff4 KVM: selftests: Rename vm_vcpu_add* helpers to better show relationships
Rename vm_vcpu_add() to __vm_vcpu_add(), and vm_vcpu_add_default() to
vm_vcpu_add() to show the relationship between the newly minted
vm_vcpu_add() and __vm_vcpu_add().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:04 -04:00
Sean Christopherson
1422efd6bb KVM: selftests: Return created vcpu from vm_vcpu_add_default()
Return the created 'struct kvm_vcpu' object from vm_vcpu_add_default(),
which cleans up a few tests and will eventually allow removing vcpu_get()
entirely.

Opportunistically rename @vcpuid to @vcpu_id to follow preferred kernel
style.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:03 -04:00
Sean Christopherson
9931be3fc6 KVM: selftests: Add "arch" to common utils that have arch implementations
Add "arch" into the name of utility functions that are declared in common
code, but (surprise!) have arch-specific implementations.  Shuffle code
around so that all such helpers' declarations are bundled together.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:03 -04:00
Sean Christopherson
b859244837 KVM: selftests: Move vm_is_unrestricted_guest() to x86-64
An "unrestricted guest" is an VMX-only concept, move the relevant helper
to x86-64 code.  Assume most readers can correctly convert underscores to
spaces and oppurtunistically trim the function comment.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:47:02 -04:00
Sean Christopherson
6ebfef83f0 KVM: selftest: Add proper helpers for x86-specific save/restore ioctls
Add helpers for the various one-off helpers used by x86's vCPU state
save/restore helpers, and convert the other open coded ioctl()s to use
existing helpers.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:46:29 -04:00
Sean Christopherson
877bd3997c KVM: selftests: Rename MP_STATE and GUEST_DEBUG helpers for consistency
Move the get/set part of the MP_STATE and GUEST_DEBUG helpers to the end
to align with the many other ioctl() wrappers/helpers.  Note, this is not
an endorsement of the predominant style, the goal is purely to provide
consistency in the selftests.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:46:28 -04:00
Sean Christopherson
2128e30b01 KVM: selftests: Dedup MSR index list helpers, simplify dedicated test
Consolidate the helper for retrieving the list of save/restore MSRs and
the list of feature MSRs, and use the common helpers in the related
get_msr_index_features test.  Switching to the common helpers eliminates
the testcase that KVM returns the same -E2BIG result if the input number
of MSRs is '1' versus '0', but considered that testcase isn't very
interesting, e.g. '0' and '1' are equally arbitrary, and certainly not
worth the additional code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:46:28 -04:00
Sean Christopherson
c095cb609b KVM: selftests: Cache list of MSRs to save/restore
Cache the list of MSRs to save restore, mostly to justify not freeing the
list in the caller, which simplifies consumption of the list.

Opportunistically move the XSS test's so called is_supported_msr() to
common code as kvm_msr_is_in_save_restore_list().  The XSS is "supported"
by KVM, it's simply not in the save/restore list because KVM doesn't yet
allow a non-zero value.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-11 11:46:26 -04:00