kernel/tools/testing/selftests/kvm/include, branch linux-6.2.y

Merge remote-tracking branch 'kvm/queue' into HEAD

2022-12-12T20:54:07Z

x86 Xen-for-KVM: * Allow the Xen runstate information to cross a page boundary * Allow XEN_RUNSTATE_UPDATE flag behaviour to be configured * add support for 32-bit guests in SCHEDOP_poll x86 fixes: * One-off fixes for various emulation flows (SGX, VMXON, NRIPS=0). * Reinstate IBPB on emulated VM-Exit that was incorrectly dropped a few years back when eliminating unnecessary barriers when switching between vmcs01 and vmcs02. * Clean up the MSR filter docs. * Clean up vmread_error_trampoline() to make it more obvious that params must be passed on the stack, even for x86-64. * Let userspace set all supported bits in MSR_IA32_FEAT_CTL irrespective of the current guest CPUID. * Fudge around a race with TSC refinement that results in KVM incorrectly thinking a guest needs TSC scaling when running on a CPU with a constant TSC, but no hardware-enumerated TSC frequency. * Advertise (on AMD) that the SMM_CTL MSR is not supported * Remove unnecessary exports Selftests: * Fix an inverted check in the access tracking perf test, and restore support for asserting that there aren't too many idle pages when running on bare metal. * Fix an ordering issue in the AMX test introduced by recent conversions to use kvm_cpu_has(), and harden the code to guard against similar bugs in the future. Anything that tiggers caching of KVM's supported CPUID, kvm_cpu_has() in this case, effectively hides opt-in XSAVE features if the caching occurs before the test opts in via prctl(). * Fix build errors that occur in certain setups (unsure exactly what is unique about the problematic setup) due to glibc overriding static_assert() to a variant that requires a custom message. * Introduce actual atomics for clear/set_bit() in selftests Documentation: * Remove deleted ioctls from documentation * Various fixes

KVM: arm64: selftests: Align VA space allocator with TTBR0

2022-12-09T08:13:35Z

An interesting feature of the Arm architecture is that the stage-1 MMU supports two distinct VA regions, controlled by TTBR{0,1}_EL1. As KVM selftests on arm64 only uses TTBR0_EL1, the VA space is constrained to [0, 2^(va_bits-1)). This is different from other architectures that allow for addressing low and high regions of the VA space from a single page table. KVM selftests' VA space allocator presumes the valid address range is split between low and high memory based the MSB, which of course is a poor match for arm64's TTBR0 region. Allow architectures to override the default VA space layout. Make use of the override to align vpages_valid with the behavior of TTBR0 on arm64. Signed-off-by: Oliver Upton Message-Id: <20221207214809.489070-4-oliver.upton@linux.dev> Signed-off-by: Paolo Bonzini

Merge tag 'kvmarm-6.2' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2022-12-09T08:12:12Z

KVM/arm64 updates for 6.2 - Enable the per-vcpu dirty-ring tracking mechanism, together with an option to keep the good old dirty log around for pages that are dirtied by something other than a vcpu. - Switch to the relaxed parallel fault handling, using RCU to delay page table reclaim and giving better performance under load. - Relax the MTE ABI, allowing a VMM to use the MAP_SHARED mapping option, which multi-process VMMs such as crosvm rely on. - Merge the pKVM shadow vcpu state tracking that allows the hypervisor to have its own view of a vcpu, keeping that state private. - Add support for the PMUv3p5 architecture revision, bringing support for 64bit counters on systems that support it, and fix the no-quite-compliant CHAIN-ed counter support for the machines that actually exist out there. - Fix a handful of minor issues around 52bit VA/PA support (64kB pages only) as a prefix of the oncoming support for 4kB and 16kB pages. - Add/Enable/Fix a bunch of selftests covering memslots, breakpoints, stage-2 faults and access tracking. You name it, we got it, we probably broke it. - Pick a small set of documentation and spelling fixes, because no good merge window would be complete without those. As a side effect, this tag also drags: - The 'kvmarm-fixes-6.1-3' tag as a dependency to the dirty-ring series - A shared branch with the arm64 tree that repaints all the system registers to match the ARM ARM's naming, and resulting in interesting conflicts

Merge branch kvm-arm64/selftest/access-tracking into kvmarm-master/next

2022-12-05T14:16:55Z

* kvm-arm64/selftest/access-tracking: : . : Small series to add support for arm64 to access_tracking_perf_test and : correct a couple bugs along the way. : : Patches courtesy of Oliver Upton. : . KVM: selftests: Build access_tracking_perf_test for arm64 KVM: selftests: Have perf_test_util signal when to stop vCPUs Signed-off-by: Marc Zyngier

KVM: arm64: selftests: Enable single-step without a "full" ucall()

2022-12-02T18:22:31Z

Add a new ucall hook, GUEST_UCALL_NONE(), to allow tests to make ucalls without allocating a ucall struct, and use it to enable single-step in ARM's debug-exceptions test. Like the disable single-step path, the enabling path also needs to ensure that no exclusive access sequences are attempted after enabling single-step, as the exclusive monitor is cleared on ERET from the debug exception taken to EL2. The test currently "works" because clear_bit() isn't actually an atomic operation... yet. Signed-off-by: Sean Christopherson Message-Id: <20221119013450.2643007-4-seanjc@google.com> Signed-off-by: Paolo Bonzini

Merge tag 'kvm-x86-fixes-6.2-1' of https://github.com/kvm-x86/linux into HEAD

2022-12-02T17:56:25Z

Misc KVM x86 fixes and cleanups for 6.2: - One-off fixes for various emulation flows (SGX, VMXON, NRIPS=0). - Reinstate IBPB on emulated VM-Exit that was incorrectly dropped a few years back when eliminating unnecessary barriers when switching between vmcs01 and vmcs02. - Clean up the MSR filter docs. - Clean up vmread_error_trampoline() to make it more obvious that params must be passed on the stack, even for x86-64. - Let userspace set all supported bits in MSR_IA32_FEAT_CTL irrespective of the current guest CPUID. - Fudge around a race with TSC refinement that results in KVM incorrectly thinking a guest needs TSC scaling when running on a CPU with a constant TSC, but no hardware-enumerated TSC frequency.

KVM: selftests: Define and use a custom static assert in lib headers

2022-12-01T23:31:46Z

Define and use kvm_static_assert() in the common KVM selftests headers to provide deterministic behavior, and to allow creating static asserts without dummy messages. The kernel's static_assert() makes the message param optional, and on the surface, tools/include/linux/build_bug.h appears to follow suit. However, glibc may override static_assert() and redefine it as a direct alias of _Static_assert(), which makes the message parameter mandatory. This leads to non-deterministic behavior as KVM selftests code that utilizes static_assert() without a custom message may or not compile depending on the order of includes. E.g. recently added asserts in x86_64/processor.h fail on some systems with errors like In file included from lib/memstress.c:11:0: include/x86_64/processor.h: In function ‘this_cpu_has_p’: include/x86_64/processor.h:193:34: error: expected ‘,’ before ‘)’ token static_assert(low_bit < high_bit); \ ^ due to _Static_assert() expecting a comma before a message. The "message optional" version of static_assert() uses macro magic to strip away the comma when presented with empty an __VA_ARGS__ #ifndef static_assert #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) #endif // static_assert and effectively generates "_Static_assert(expr, #expr)". The incompatible version of static_assert() gets defined by this snippet in /usr/include/assert.h: #if defined __USE_ISOC11 && !defined __cplusplus # undef static_assert # define static_assert _Static_assert #endif which yields "_Static_assert(expr)" and thus fails as above. KVM selftests don't actually care about using C11, but __USE_ISOC11 gets defined because of _GNU_SOURCE, which many tests do #define. _GNU_SOURCE triggers a massive pile of defines in /usr/include/features.h, including _ISOC11_SOURCE: /* If _GNU_SOURCE was defined by the user, turn on all the other features. */ #ifdef _GNU_SOURCE # undef _ISOC95_SOURCE # define _ISOC95_SOURCE 1 # undef _ISOC99_SOURCE # define _ISOC99_SOURCE 1 # undef _ISOC11_SOURCE # define _ISOC11_SOURCE 1 # undef _POSIX_SOURCE # define _POSIX_SOURCE 1 # undef _POSIX_C_SOURCE # define _POSIX_C_SOURCE 200809L # undef _XOPEN_SOURCE # define _XOPEN_SOURCE 700 # undef _XOPEN_SOURCE_EXTENDED # define _XOPEN_SOURCE_EXTENDED 1 # undef _LARGEFILE64_SOURCE # define _LARGEFILE64_SOURCE 1 # undef _DEFAULT_SOURCE # define _DEFAULT_SOURCE 1 # undef _ATFILE_SOURCE # define _ATFILE_SOURCE 1 #endif which further down in /usr/include/features.h leads to: /* This is to enable the ISO C11 extension. */ #if (defined _ISOC11_SOURCE \ || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)) # define __USE_ISOC11 1 #endif To make matters worse, /usr/include/assert.h doesn't guard against multiple inclusion by turning itself into a nop, but instead #undefs a few macros and continues on. As a result, it's all but impossible to ensure the "message optional" version of static_assert() will actually be used, e.g. explicitly including assert.h and #undef'ing static_assert() doesn't work as a later inclusion of assert.h will again redefine its version. #ifdef _ASSERT_H # undef _ASSERT_H # undef assert # undef __ASSERT_VOID_CAST # ifdef __USE_GNU # undef assert_perror # endif #endif /* assert.h */ #define _ASSERT_H 1 #include Fixes: fcba483e8246 ("KVM: selftests: Sanity check input to ioctls() at build time") Fixes: ee3795536664 ("KVM: selftests: Refactor X86_FEATURE_* framework to prep for X86_PROPERTY_*") Fixes: 53a7dc0f215e ("KVM: selftests: Add X86_PROPERTY_* framework to retrieve CPUID values") Signed-off-by: Sean Christopherson Link: https://lore.kernel.org/r/20221122013309.1872347-1-seanjc@google.com

KVM: selftests: Restore assert for non-nested VMs in access tracking test

2022-12-01T23:31:39Z

Restore the assert (on x86-64) that <10% of pages are still idle when NOT running as a nested VM in the access tracking test. The original assert was converted to a "warning" to avoid false failures when running the test in a VM, but the non-nested case does not suffer from the same "infinite TLB size" issue. Using the HYPERVISOR flag isn't infallible as VMMs aren't strictly required to enumerate the "feature" in CPUID, but practically speaking anyone that is running KVM selftests in VMs is going to be using a VMM and hypervisor that sets the HYPERVISOR flag. Cc: David Matlack Reviewed-by: Emanuele Giuseppe Esposito Signed-off-by: Sean Christopherson Link: https://lore.kernel.org/r/20221129175300.4052283-3-seanjc@google.com

KVM: selftests: Verify userspace can stuff IA32_FEATURE_CONTROL at will

2022-12-01T00:29:54Z

Verify the KVM allows userspace to set all supported bits in the IA32_FEATURE_CONTROL MSR irrespective of the current guest CPUID, and that all unsupported bits are rejected. Throw the testcase into vmx_msrs_test even though it's not technically a VMX MSR; it's close enough, and the most frequently feature controlled by the MSR is VMX. Signed-off-by: Sean Christopherson Link: https://lore.kernel.org/r/20220607232353.3375324-4-seanjc@google.com

KVM: selftests: Have perf_test_util signal when to stop vCPUs

2022-11-29T17:29:42Z

Signal that a test run is complete through perf_test_args instead of having tests open code a similar solution. Ensure that the field resets to false at the beginning of a test run as the structure is reused between test runs, eliminating a couple of bugs: access_tracking_perf_test hangs indefinitely on a subsequent test run, as 'done' remains true. The bug doesn't amount to much right now, as x86 supports a single guest mode. However, this is a precondition of enabling the test for other architectures with >1 guest mode, like arm64. memslot_modification_stress_test has the exact opposite problem, where subsequent test runs complete immediately as 'run_vcpus' remains false. Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson [oliver: added commit message, preserve spin_wait_for_next_iteration()] Signed-off-by: Oliver Upton Reviewed-by: Gavin Shan Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20221118211503.4049023-2-oliver.upton@linux.dev