blaster4385/linux-IllusionX/tools/testing/selftests/kvm/include/x86_64/processor.h, branch v6.13

KVM: selftests: Configure XCR0 to max supported value by default

2024-11-01T16:26:31Z

To play nice with compilers generating AVX instructions, set CR4.OSXSAVE and configure XCR0 by default when creating selftests vCPUs. Some distros have switched gcc to '-march=x86-64-v3' by default, and while it's hard to find a CPU which doesn't support AVX today, many KVM selftests fail with ==== Test Assertion Failure ==== lib/x86_64/processor.c:570: Unhandled exception in guest pid=72747 tid=72747 errno=4 - Interrupted system call Unhandled exception '0x6' at guest RIP '0x4104f7' due to selftests not enabling AVX by default for the guest. The failure is easy to reproduce elsewhere with: $ make clean && CFLAGS='-march=x86-64-v3' make -j && ./x86_64/kvm_pv_test E.g. gcc-13 with -march=x86-64-v3 compiles this chunk from selftests' kvm_fixup_exception(): regs->rip = regs->r11; regs->r9 = regs->vector; regs->r10 = regs->error_code; into this monstronsity (which is clever, but oof): 405313: c4 e1 f9 6e c8 vmovq %rax,%xmm1 405318: 48 89 68 08 mov %rbp,0x8(%rax) 40531c: 48 89 e8 mov %rbp,%rax 40531f: c4 c3 f1 22 c4 01 vpinsrq $0x1,%r12,%xmm1,%xmm0 405325: 49 89 6d 38 mov %rbp,0x38(%r13) 405329: c5 fa 7f 45 00 vmovdqu %xmm0,0x0(%rbp) Alternatively, KVM selftests could explicitly restrict the compiler to -march=x86-64-v2, but odds are very good that punting on AVX enabling will simply result in tests that "need" AVX doing their own thing, e.g. there are already three or so additional cleanups that can be done on top. Reported-by: Vitaly Kuznetsov Closes: https://lore.kernel.org/all/20240920154422.2890096-1-vkuznets@redhat.com Reviewed-and-tested-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20241003234337.273364-6-seanjc@google.com Signed-off-by: Sean Christopherson

KVM: selftests: Move Hyper-V specific functions out of processor.c

2024-08-22T19:14:42Z

Since there is 'hyperv.c' for Hyper-V specific functions already, move Hyper-V specific functions out of processor.c there. No functional change intended. Signed-off-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20240816130139.286246-2-vkuznets@redhat.com Signed-off-by: Sean Christopherson

Merge tag 'kvm-x86-misc-6.11' of https://github.com/kvm-x86/linux into HEAD

2024-07-16T13:53:05Z

KVM x86 misc changes for 6.11 - Add a global struct to consolidate tracking of host values, e.g. EFER, and move "shadow_phys_bits" into the structure as "maxphyaddr". - Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the effective APIC bus frequency, because TDX. - Print the name of the APICv/AVIC inhibits in the relevant tracepoint. - Clean up KVM's handling of vendor specific emulation to consistently act on "compatible with Intel/AMD", versus checking for a specific vendor. - Misc cleanups

KVM: selftests: Add guest udelay() utility for x86

2024-06-28T18:40:38Z

Add udelay() for x86 tests to allow busy waiting in the guest for a specific duration, and to match ARM and RISC-V's udelay() in the hopes of eventually making udelay() available on all architectures. Get the guest's TSC frequency using KVM_GET_TSC_KHZ and expose it to all VMs via a new global, guest_tsc_khz. Assert that KVM_GET_TSC_KHZ returns a valid frequency, instead of simply skipping tests, which would require detecting which tests actually need/want udelay(). KVM hasn't returned an error for KVM_GET_TSC_KHZ since commit cc578287e322 ("KVM: Infrastructure for software and hardware based TSC rate scaling"), which predates KVM selftests by 6+ years (KVM_GET_TSC_KHZ itself predates KVM selftest by 7+ years). Note, if the GUEST_ASSERT() in udelay() somehow fires and the test doesn't check for guest asserts, then the test will fail with a very cryptic message. But fixing that, e.g. by automatically handling guest asserts, is a much larger task, and practically speaking the odds of a test afoul of this wart are infinitesimally small. Signed-off-by: Reinette Chatre Link: https://lore.kernel.org/r/5aa86285d1c1d7fe1960e3fe490f4b22273977e6.1718214999.git.reinette.chatre@intel.com Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson

KVM: selftests: x86: Prioritize getting max_gfn from GuestPhysBits

2024-06-05T13:16:10Z

Use the max mappable GPA via GuestPhysBits advertised by KVM to calculate max_gfn. Currently some selftests (e.g. access_tracking_perf_test, dirty_log_test...) add RAM regions close to max_gfn, so guest may access GPA beyond its mappable range and cause infinite loop. Adjust max_gfn in vm_compute_max_gfn() since x86 selftests already overrides vm_compute_max_gfn() specifically to deal with goofy edge cases. Reported-by: Yi Lai Signed-off-by: Tao Su Tested-by: Yi Lai Reviewed-by: Xiaoyao Li Link: https://lore.kernel.org/r/20240513014003.104593-1-tao1.su@linux.intel.com [sean: tweak name, add comment and sanity check] Signed-off-by: Sean Christopherson

KVM: selftests: Init IDT and exception handlers for all VMs/vCPUs on x86

2024-04-29T19:55:15Z

Initialize the IDT and exception handlers for all non-barebones VMs and vCPUs on x86. Forcing tests to manually configure the IDT just to save 8KiB of memory is a terrible tradeoff, and also leads to weird tests (multiple tests have deliberately relied on shutdown to indicate success), and hard-to-debug failures, e.g. instead of a precise unexpected exception failure, tests see only shutdown. Reviewed-by: Ackerley Tng Link: https://lore.kernel.org/r/20240314232637.2538648-11-seanjc@google.com Signed-off-by: Sean Christopherson

Revert "kvm: selftests: move base kvm_util.h declarations to kvm_util_base.h"

2024-04-29T19:54:13Z

Effectively revert the movement of code from kvm_util.h => kvm_util_base.h, as the TL;DR of the justification for the move was to avoid #idefs and/or circular dependencies between what ended up being ucall_common.h and what was (and now again, is), kvm_util.h. But avoiding #ifdef and circular includes is trivial: don't do that. The cost of removing kvm_util_base.h is a few extra includes of ucall_common.h, but that cost is practically nothing. On the other hand, having a "base" version of a header that is really just the header itself is confusing, and makes it weird/hard to choose names for headers that actually are "base" headers, e.g. to hold core KVM selftests typedefs. For all intents and purposes, this reverts commit 7d9a662ed9f0403e7b94940dceb81552b8edb931. Reviewed-by: Ackerley Tng Link: https://lore.kernel.org/r/20240314232637.2538648-2-seanjc@google.com Signed-off-by: Sean Christopherson

selftests: kvm: switch to using KVM_X86_*_VM

2024-04-11T17:08:27Z

This removes the concept of "subtypes", instead letting the tests use proper VM types that were recently added. While the sev_init_vm() and sev_es_init_vm() are still able to operate with the legacy KVM_SEV_INIT and KVM_SEV_ES_INIT ioctls, this is limited to VMs that are created manually with vm_create_barebones(). Signed-off-by: Paolo Bonzini Message-ID: <20240404121327.3107131-16-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini

Merge tag 'kvm-x86-pvunhalt-6.9' of https://github.com/kvm-x86/linux into HEAD

2024-03-18T23:19:08Z

Fix a bug in KVM_SET_CPUID{2,} where KVM looks at the wrong CPUID entries (old vs. new) and ultimately neglects to clear PV_UNHALT from vCPUs with HLT-exiting disabled.

Merge tag 'kvm-x86-pmu-6.9' of https://github.com/kvm-x86/linux into HEAD

2024-03-11T14:41:09Z

KVM x86 PMU changes for 6.9: - Fix several bugs where KVM speciously prevents the guest from utilizing fixed counters and architectural event encodings based on whether or not guest CPUID reports support for the _architectural_ encoding. - Fix a variety of bugs in KVM's emulation of RDPMC, e.g. for "fast" reads, priority of VMX interception vs #GP, PMC types in architectural PMUs, etc. - Add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID, i.e. are difficult to validate via KVM-Unit-Tests. - Zero out PMU metadata on AMD if the virtual PMU is disabled to avoid wasting cycles, e.g. when checking if a PMC event needs to be synthesized when skipping an instruction. - Optimize triggering of emulated events, e.g. for "count instructions" events when skipping an instruction, which yields a ~10% performance improvement in VM-Exit microbenchmarks when a vPMU is exposed to the guest. - Tighten the check for "PMI in guest" to reduce false positives if an NMI arrives in the host while KVM is handling an IRQ VM-Exit.