Mimic the dirty log test and allow the user to pin demand paging test
tasks to physical CPUs.

Put the help message into a general helper as suggested by Sean.

Signed-off-by: Peter Xu <peterx@redhat.com>
[sean: rebase, tweak arg ordering, add "print" to helper, print program name]
Link: https://lore.kernel.org/r/20230607001226.1398889-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Move some helper functions from dirty_log_perf_test.c to the memstress
library so that they can be used in a future commit which tests page
splitting during dirty logging.

Reviewed-by: Vipin Sharma <vipinsh@google.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Link: https://lore.kernel.org/r/20230131181820.179033-2-bgardon@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Access the same memory addresses on each iteration of the memstress
guest code.  This ensures that the state of KVM's page tables
is the same after every iteration, including the pages that host the
guest page tables for args and vcpu_args.

This difference is visible when running the proposed
dirty_log_page_splitting_test[*] on AMD, or on Intel with pml=0 and
eptad=0.  The tests fail due to different semantics of dirty bits for
page-table pages on AMD (and eptad=0) and Intel.  Both AMD and Intel with
eptad=0 treat page-table accesses as writes, therefore more pages are
dropped before the repopulation phase when dirty logging is disabled.

The "missing" page had been included in the population phase because it
hosts the page tables for vcpu_args, but repopulation does not need it."

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Vipin Sharma <vipinsh@google.com>
Link: https://lore.kernel.org/r/20230412200913.1570873-1-pbonzini@redhat.com
[sean: add additional details in changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>

There's one PER_VCPU_DEBUG in per-vcpu uffd threads but it's never hit.

Trigger that when quit in normal ways (kick pollfd[1]), meanwhile fix the
number of nanosec calculation.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: James Houghton <jthoughton@google.com>
Link: https://lore.kernel.org/r/20230427201112.2164776-3-peterx@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM selftests, and an AMX/XCR0 bugfix, for 6.4:

 - Don't advertise XTILE_CFG in KVM_GET_SUPPORTED_CPUID if XTILE_DATA is
   not being reported due to userspace not opting in via prctl()

 - Overhaul the AMX selftests to improve coverage and cleanup the test

 - Misc cleanups

* kvm-arm64/smccc-filtering:
  : .
  : SMCCC call filtering and forwarding to userspace, courtesy of
  : Oliver Upton. From the cover letter:
  :
  : "The Arm SMCCC is rather prescriptive in regards to the allocation of
  : SMCCC function ID ranges. Many of the hypercall ranges have an
  : associated specification from Arm (FF-A, PSCI, SDEI, etc.) with some
  : room for vendor-specific implementations.
  :
  : The ever-expanding SMCCC surface leaves a lot of work within KVM for
  : providing new features. Furthermore, KVM implements its own
  : vendor-specific ABI, with little room for other implementations (like
  : Hyper-V, for example). Rather than cramming it all into the kernel we
  : should provide a way for userspace to handle hypercalls."
  : .
  KVM: selftests: Fix spelling mistake "KVM_HYPERCAL_EXIT_SMC" -> "KVM_HYPERCALL_EXIT_SMC"
  KVM: arm64: Test that SMC64 arch calls are reserved
  KVM: arm64: Prevent userspace from handling SMC64 arch range
  KVM: arm64: Expose SMC/HVC width to userspace
  KVM: selftests: Add test for SMCCC filter
  KVM: selftests: Add a helper for SMCCC calls with SMC instruction
  KVM: arm64: Let errors from SMCCC emulation to reach userspace
  KVM: arm64: Return NOT_SUPPORTED to guest for unknown PSCI version
  KVM: arm64: Introduce support for userspace SMCCC filtering
  KVM: arm64: Add support for KVM_EXIT_HYPERCALL
  KVM: arm64: Use a maple tree to represent the SMCCC filter
  KVM: arm64: Refactor hvc filtering to support different actions
  KVM: arm64: Start handling SMCs from EL1
  KVM: arm64: Rename SMC/HVC call handler to reflect reality
  KVM: arm64: Add vm fd device attribute accessors
  KVM: arm64: Add a helper to check if a VM has ran once
  KVM: x86: Redefine 'longmode' as a flag for KVM_EXIT_HYPERCALL

Signed-off-by: Marc Zyngier <maz@kernel.org>

There is a spelling mistake in a test report message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20230414080809.1678603-1-colin.i.king@gmail.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Take the XFeature mask in __vm_xsave_require_permission() instead of the
bit so that there's no need to define macros for both the bit and the
mask.  Asserting that only a single bit is set and retrieving said bit
is easy enough via log2 helpers.

Opportunistically clean up the error message for the
ARCH_REQ_XCOMP_GUEST_PERM sanity check.

Reviewed-by: Aaron Lewis <aaronlewis@google.com>
Tested-by: Aaron Lewis <aaronlewis@google.com>
Link: https://lore.kernel.org/r/20230405004520.421768-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Build a helper for doing SMCs in selftests by macro-izing the current
HVC implementation and taking the conduit instruction as an argument.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230404154050.2270077-13-oliver.upton@linux.dev

Bits [51:48] of the pgd address are stored at bits [5:2] of ttbr0_el1.
page_table_test stores its page tables at the far end of IPA space so
was tripping over this when run on a system that supports FEAT_LPA (or
FEAT_LPA2).

Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230308110948.1820163-4-ryan.roberts@arm.com