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2024-12-18KVM: selftests: Fix a bad TEST_REQUIRE() in x86's KVM PV testSean Christopherson
Actually check for KVM support for disabling HLT-exiting instead of effectively checking that KVM_CAP_X86_DISABLE_EXITS is #defined to a non-zero value, and convert the TEST_REQUIRE() to a simple return so that only the sub-test is skipped if HLT-exiting is mandatory. The goof has likely gone unnoticed because all x86 CPUs support disabling HLT-exiting, only systems with the opt-in mitigate_smt_rsb KVM module param disallow HLT-exiting. Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-17-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Drop the now unused KVM_X86_DISABLE_VALID_EXITSSean Christopherson
Drop the KVM_X86_DISABLE_VALID_EXITS definition, as it is misleading, and unused in KVM *because* it is misleading. The set of exits that can be disabled is dynamic, i.e. userspace (and KVM) must check KVM's actual capabilities. Suggested-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-16-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Reject disabling of MWAIT/HLT interception when not allowedSean Christopherson
Reject KVM_CAP_X86_DISABLE_EXITS if userspace attempts to disable MWAIT or HLT exits and KVM previously reported (via KVM_CHECK_EXTENSION) that disabling the exit(s) is not allowed. E.g. because MWAIT isn't supported or the CPU doesn't have an always-running APIC timer, or because KVM is configured to mitigate cross-thread vulnerabilities. Cc: Kechen Lu <kechenl@nvidia.com> Fixes: 4d5422cea3b6 ("KVM: X86: Provide a capability to disable MWAIT intercepts") Fixes: 6f0f2d5ef895 ("KVM: x86: Mitigate the cross-thread return address predictions bug") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-15-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Disallow KVM_CAP_X86_DISABLE_EXITS after vCPU creationSean Christopherson
Reject KVM_CAP_X86_DISABLE_EXITS if vCPUs have been created, as disabling PAUSE/MWAIT/HLT exits after vCPUs have been created is broken and useless, e.g. except for PAUSE on SVM, the relevant intercepts aren't updated after vCPU creation. vCPUs may also end up with an inconsistent configuration if exits are disabled between creation of multiple vCPUs. Cc: Hou Wenlong <houwenlong.hwl@antgroup.com> Link: https://lore.kernel.org/all/9227068821b275ac547eb2ede09ec65d2281fe07.1680179693.git.houwenlong.hwl@antgroup.com Link: https://lore.kernel.org/all/20230121020738.2973-2-kechenl@nvidia.com Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-14-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Drop now-redundant MAXPHYADDR and GPA rsvd bits from vCPU creationSean Christopherson
Drop the manual initialization of maxphyaddr and reserved_gpa_bits during vCPU creation now that kvm_arch_vcpu_create() unconditionally invokes kvm_vcpu_after_set_cpuid(), which handles all such CPUID caching. None of the helpers between the existing code in kvm_arch_vcpu_create() and the call to kvm_vcpu_after_set_cpuid() consume maxphyaddr or reserved_gpa_bits (though auditing vmx_vcpu_create() and svm_vcpu_create() isn't exactly easy). Link: https://lore.kernel.org/r/20241128013424.4096668-13-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86/pmu: Drop now-redundant refresh() during init()Sean Christopherson
Drop the manual kvm_pmu_refresh() from kvm_pmu_init() now that kvm_arch_vcpu_create() performs the refresh via kvm_vcpu_after_set_cpuid(). Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Link: https://lore.kernel.org/r/20241128013424.4096668-12-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Move __kvm_is_valid_cr4() definition to x86.hSean Christopherson
Let vendor code inline __kvm_is_valid_cr4() now x86.c's cr4_reserved_bits no longer exists, as keeping cr4_reserved_bits local to x86.c was the only reason for "hiding" the definition of __kvm_is_valid_cr4(). No functional change intended. Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Link: https://lore.kernel.org/r/20241128013424.4096668-11-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Verify KVM stuffs runtime CPUID OS bits on CR4 writesSean Christopherson
Extend x86's set sregs test to verify that KVM sets/clears OSXSAVE and OSKPKE according to CR4.XSAVE and CR4.PKE respectively. For performance reasons, KVM is responsible for emulating the architectural behavior of the OS CPUID bits tracking CR4. Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-10-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Refresh vCPU CPUID cache in __vcpu_get_cpuid_entry()Sean Christopherson
Refresh selftests' CPUID cache in the vCPU structure when querying a CPUID entry so that tests don't consume stale data when KVM modifies CPUID as a side effect to a completely unrelated change. E.g. KVM adjusts OSXSAVE in response to CR4.OSXSAVE changes. Unnecessarily invoking KVM_GET_CPUID is suboptimal, but vcpu->cpuid exists to simplify selftests development, not for performance reasons. And, unfortunately, trying to handle the side effects in tests or other flows is unpleasant, e.g. selftests could manually refresh if KVM_SET_SREGS is successful, but that would still leave a gap with respect to guest CR4 changes. Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Link: https://lore.kernel.org/r/20241128013424.4096668-9-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Assert that vcpu->cpuid is non-NULL when getting CPUID entriesSean Christopherson
Add a sanity check in __vcpu_get_cpuid_entry() to provide a friendlier error than a segfault when a test developer tries to use a vCPU CPUID helper on a barebones vCPU. Link: https://lore.kernel.org/r/20241128013424.4096668-8-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Update x86's set_sregs_test to match KVM's CPUID enforcementSean Christopherson
Rework x86's set sregs test to verify that KVM enforces CPUID vs. CR4 features even if userspace hasn't explicitly set guest CPUID. KVM used to allow userspace to set any KVM-supported CR4 value prior to KVM_SET_CPUID2, and the test verified that behavior. However, the testcase was written purely to verify KVM's existing behavior, i.e. was NOT written to match the needs of real world VMMs. Opportunistically verify that KVM continues to reject unsupported features after KVM_SET_CPUID2 (using KVM_GET_SUPPORTED_CPUID). Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Account for KVM-reserved CR4 bits when passing through CR4 on VMXSean Christopherson
Drop x86.c's local pre-computed cr4_reserved bits and instead fold KVM's reserved bits into the guest's reserved bits. This fixes a bug where VMX's set_cr4_guest_host_mask() fails to account for KVM-reserved bits when deciding which bits can be passed through to the guest. In most cases, letting the guest directly write reserved CR4 bits is ok, i.e. attempting to set the bit(s) will still #GP, but not if a feature is available in hardware but explicitly disabled by the host, e.g. if FSGSBASE support is disabled via "nofsgsbase". Note, the extra overhead of computing host reserved bits every time userspace sets guest CPUID is negligible. The feature bits that are queried are packed nicely into a handful of words, and so checking and setting each reserved bit costs in the neighborhood of ~5 cycles, i.e. the total cost will be in the noise even if the number of checked CR4 bits doubles over the next few years. In other words, x86 will run out of CR4 bits long before the overhead becomes problematic. Note #2, __cr4_reserved_bits() starts from CR4_RESERVED_BITS, which is why the existing __kvm_cpu_cap_has() processing doesn't explicitly OR in CR4_RESERVED_BITS (and why the new code doesn't do so either). Fixes: 2ed41aa631fc ("KVM: VMX: Intercept guest reserved CR4 bits to inject #GP fault") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Link: https://lore.kernel.org/r/20241128013424.4096668-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Explicitly do runtime CPUID updates "after" initial setupSean Christopherson
Explicitly perform runtime CPUID adjustments as part of the "after set CPUID" flow to guard against bugs where KVM consumes stale vCPU/CPUID state during kvm_update_cpuid_runtime(). E.g. see commit 4736d85f0d18 ("KVM: x86: Use actual kvm_cpuid.base for clearing KVM_FEATURE_PV_UNHALT"). Whacking each mole individually is not sustainable or robust, e.g. while the aforemention commit fixed KVM's PV features, the same issue lurks for Xen and Hyper-V features, Xen and Hyper-V simply don't have any runtime features (though spoiler alert, neither should KVM). Updating runtime features in the "full" path will also simplify adding a snapshot of the guest's capabilities, i.e. of caching the intersection of guest CPUID and kvm_cpu_caps (modulo a few edge cases). Link: https://lore.kernel.org/r/20241128013424.4096668-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Do all post-set CPUID processing during vCPU creationSean Christopherson
During vCPU creation, process KVM's default, empty CPUID as if userspace set an empty CPUID to ensure consistent and correct behavior with respect to guest CPUID. E.g. if userspace never sets guest CPUID, KVM will never configure cr4_guest_rsvd_bits, and thus create divergent, incorrect, guest- visible behavior due to letting the guest set any KVM-supported CR4 bits despite the features not being allowed per guest CPUID. Note! This changes KVM's ABI, as lack of full CPUID processing allowed userspace to stuff garbage vCPU state, e.g. userspace could set CR4 to a guest-unsupported value via KVM_SET_SREGS. But it's extremely unlikely that this is a breaking change, as KVM already has many flows that require userspace to set guest CPUID before loading vCPU state. E.g. multiple MSR flows consult guest CPUID on host writes, and KVM_SET_SREGS itself already relies on guest CPUID being up-to-date, as KVM's validity check on CR3 consumes CPUID.0x7.1 (for LAM) and CPUID.0x80000008 (for MAXPHYADDR). Furthermore, the plan is to commit to enforcing guest CPUID for userspace writes to MSRs, at which point bypassing sregs CPUID checks is even more nonsensical. Link: https://lore.kernel.org/r/20241128013424.4096668-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Limit use of F() and SF() to kvm_cpu_cap_{mask,init_kvm_defined}()Sean Christopherson
Define and undefine the F() and SF() macros precisely around kvm_set_cpu_caps() to make it all but impossible to use the macros outside of kvm_cpu_cap_{mask,init_kvm_defined}(). Currently, F() is a simple passthrough, but SF() is actively dangerous as it checks that the scattered feature is supported by the host kernel. And usage outside of the aforementioned helpers will run afoul of future changes to harden KVM's CPUID management. Opportunistically switch to feature_bit() when stuffing LA57 based on raw hardware support. No functional change intended. Link: https://lore.kernel.org/r/20241128013424.4096668-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: x86: Use feature_bit() to clear CONSTANT_TSC when emulating CPUIDSean Christopherson
When clearing CONSTANT_TSC during CPUID emulation due to a Hyper-V quirk, use feature_bit() instead of SF() to ensure the bit is actually cleared. SF() evaluates to zero if the _host_ doesn't support the feature. I.e. KVM could keep the bit set if userspace advertised CONSTANT_TSC despite it not being supported in hardware. Note, translating from a scattered feature to a the hardware version is done by __feature_translate(), not SF(). The sole purpose of SF() is to check kernel support for the scattered feature, *before* translation. Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20241128013424.4096668-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Override ARCH for x86_64 instead of using ARCH_DIRSean Christopherson
Now that KVM selftests uses the kernel's canonical arch paths, directly override ARCH to 'x86' when targeting x86_64 instead of defining ARCH_DIR to redirect to appropriate paths. ARCH_DIR was originally added to deal with KVM selftests using the target triple ARCH for directories, e.g. s390x and aarch64; keeping it around just to deal with the one-off alias from x86_64=>x86 is unnecessary and confusing. Note, even when selftests are built from the top-level Makefile, ARCH is scoped to KVM's makefiles, i.e. overriding ARCH won't trip up some other selftests that (somehow) expects x86_64 and can't work with x86. Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/20241128005547.4077116-17-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Use canonical $(ARCH) paths for KVM selftests directoriesSean Christopherson
Use the kernel's canonical $(ARCH) paths instead of the raw target triple for KVM selftests directories. KVM selftests are quite nearly the only place in the entire kernel that using the target triple for directories, tools/testing/selftests/drivers/s390x being the lone holdout. Using the kernel's preferred nomenclature eliminates the minor, but annoying, friction of having to translate to KVM's selftests directories, e.g. for pattern matching, opening files, running selftests, etc. Opportunsitically delete file comments that reference the full path of the file, as they are obviously prone to becoming stale, and serve no known purpose. Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Acked-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-16-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Provide empty 'all' and 'clean' targets for unsupported ARCHsSean Christopherson
Provide empty targets for KVM selftests if the target architecture is unsupported to make it obvious which architectures are supported, and so that various side effects don't fail and/or do weird things, e.g. as is, "mkdir -p $(sort $(dir $(TEST_GEN_PROGS)))" fails due to a missing operand, and conversely, "$(shell mkdir -p $(sort $(OUTPUT)/$(ARCH_DIR) ..." will create an empty, useless directory for the unsupported architecture. Move the guts of the Makefile to Makefile.kvm so that it's easier to see that the if-statement effectively guards all of KVM selftests. Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Acked-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Acked-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-15-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Verify KVM correctly handles mprotect(PROT_READ)Sean Christopherson
Add two phases to mmu_stress_test to verify that KVM correctly handles guest memory that was writable, and then made read-only in the primary MMU, and then made writable again. Add bonus coverage for x86 and arm64 to verify that all of guest memory was marked read-only. Making forward progress (without making memory writable) requires arch specific code to skip over the faulting instruction, but the test can at least verify each vCPU's starting page was made read-only for other architectures. Link: https://lore.kernel.org/r/20241128005547.4077116-14-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Add a read-only mprotect() phase to mmu_stress_testSean Christopherson
Add a third phase of mmu_stress_test to verify that mprotect()ing guest memory to make it read-only doesn't cause explosions, e.g. to verify KVM correctly handles the resulting mmu_notifier invalidations. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-13-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Precisely limit the number of guest loops in mmu_stress_testSean Christopherson
Run the exact number of guest loops required in mmu_stress_test instead of looping indefinitely in anticipation of adding more stages that run different code (e.g. reads instead of writes). Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-12-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Use vcpu_arch_put_guest() in mmu_stress_testSean Christopherson
Use vcpu_arch_put_guest() to write memory from the guest in mmu_stress_test as an easy way to provide a bit of extra coverage. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-11-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Enable mmu_stress_test on arm64Sean Christopherson
Enable the mmu_stress_test on arm64. The intent was to enable the test across all architectures when it was first added, but a few goofs made it unrunnable on !x86. Now that those goofs are fixed, at least for arm64, enable the test. Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Marc Zyngier <maz@kernel.org> Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-10-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: sefltests: Explicitly include ucall_common.h in mmu_stress_test.cSean Christopherson
Explicitly include ucall_common.h in the MMU stress test, as unlike arm64 and x86-64, RISC-V doesn't include ucall_common.h in its processor.h, i.e. this will allow enabling the test on RISC-V. Reported-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-9-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Compute number of extra pages needed in mmu_stress_testSean Christopherson
Create mmu_stress_tests's VM with the correct number of extra pages needed to map all of memory in the guest. The bug hasn't been noticed before as the test currently runs only on x86, which maps guest memory with 1GiB pages, i.e. doesn't need much memory in the guest for page tables. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-8-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Only muck with SREGS on x86 in mmu_stress_testSean Christopherson
Try to get/set SREGS in mmu_stress_test only when running on x86, as the ioctls are supported only by x86 and PPC, and the latter doesn't yet support KVM selftests. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Rename max_guest_memory_test to mmu_stress_testSean Christopherson
Rename max_guest_memory_test to mmu_stress_test so that the name isn't horribly misleading when future changes extend the test to verify things like mprotect() interactions, and because the test is useful even when its configured to populate far less than the maximum amount of guest memory. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Check for a potential unhandled exception iff KVM_RUN succeededSean Christopherson
Don't check for an unhandled exception if KVM_RUN failed, e.g. if it returned errno=EFAULT, as reporting unhandled exceptions is done via a ucall, i.e. requires KVM_RUN to exit cleanly. Theoretically, checking for a ucall on a failed KVM_RUN could get a false positive, e.g. if there were stale data in vcpu->run from a previous exit. Reviewed-by: James Houghton <jthoughton@google.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Assert that vcpu_{g,s}et_reg() won't truncateSean Christopherson
Assert that the register being read/written by vcpu_{g,s}et_reg() is no larger than a uint64_t, i.e. that a selftest isn't unintentionally truncating the value being read/written. Ideally, the assert would be done at compile-time, but that would limit the checks to hardcoded accesses and/or require fancier compile-time assertion infrastructure to filter out dynamic usage. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20241128005547.4077116-4-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18KVM: selftests: Return a value from vcpu_get_reg() instead of using an out-paramSean Christopherson
Return a uint64_t from vcpu_get_reg() instead of having the caller provide a pointer to storage, as none of the vcpu_get_reg() usage in KVM selftests accesses a register larger than 64 bits, and vcpu_set_reg() only accepts a 64-bit value. If a use case comes along that needs to get a register that is larger than 64 bits, then a utility can be added to assert success and take a void pointer, but until then, forcing an out param yields ugly code and prevents feeding the output of vcpu_get_reg() into vcpu_set_reg(). Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Link: https://lore.kernel.org/r/20241128005547.4077116-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-17KVM: Move KVM_REG_SIZE() definition to common uAPI headerSean Christopherson
Define KVM_REG_SIZE() in the common kvm.h header, and delete the arm64 and RISC-V versions. As evidenced by the surrounding definitions, all aspects of the register size encoding are generic, i.e. RISC-V should have moved arm64's definition to common code instead of copy+pasting. Acked-by: Anup Patel <anup@brainfault.org> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/20241128005547.4077116-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-13Merge tag 'kvm-riscv-fixes-6.13-1' of https://github.com/kvm-riscv/linux ↵Paolo Bonzini
into HEAD KVM/riscv fixes for 6.13, take #1 - Replace csr_write() with csr_set() for HVIEN PMU overflow bit
2024-12-13KVM: x86: Cache CPUID.0xD XSTATE offsets+sizes during module initSean Christopherson
Snapshot the output of CPUID.0xD.[1..n] during kvm.ko initiliaization to avoid the overead of CPUID during runtime. The offset, size, and metadata for CPUID.0xD.[1..n] sub-leaves does not depend on XCR0 or XSS values, i.e. is constant for a given CPU, and thus can be cached during module load. On Intel's Emerald Rapids, CPUID is *wildly* expensive, to the point where recomputing XSAVE offsets and sizes results in a 4x increase in latency of nested VM-Enter and VM-Exit (nested transitions can trigger xstate_required_size() multiple times per transition), relative to using cached values. The issue is easily visible by running `perf top` while triggering nested transitions: kvm_update_cpuid_runtime() shows up at a whopping 50%. As measured via RDTSC from L2 (using KVM-Unit-Test's CPUID VM-Exit test and a slightly modified L1 KVM to handle CPUID in the fastpath), a nested roundtrip to emulate CPUID on Skylake (SKX), Icelake (ICX), and Emerald Rapids (EMR) takes: SKX 11650 ICX 22350 EMR 28850 Using cached values, the latency drops to: SKX 6850 ICX 9000 EMR 7900 The underlying issue is that CPUID itself is slow on ICX, and comically slow on EMR. The problem is exacerbated on CPUs which support XSAVES and/or XSAVEC, as KVM invokes xstate_required_size() twice on each runtime CPUID update, and because there are more supported XSAVE features (CPUID for supported XSAVE feature sub-leafs is significantly slower). SKX: CPUID.0xD.2 = 348 cycles CPUID.0xD.3 = 400 cycles CPUID.0xD.4 = 276 cycles CPUID.0xD.5 = 236 cycles <other sub-leaves are similar> EMR: CPUID.0xD.2 = 1138 cycles CPUID.0xD.3 = 1362 cycles CPUID.0xD.4 = 1068 cycles CPUID.0xD.5 = 910 cycles CPUID.0xD.6 = 914 cycles CPUID.0xD.7 = 1350 cycles CPUID.0xD.8 = 734 cycles CPUID.0xD.9 = 766 cycles CPUID.0xD.10 = 732 cycles CPUID.0xD.11 = 718 cycles CPUID.0xD.12 = 734 cycles CPUID.0xD.13 = 1700 cycles CPUID.0xD.14 = 1126 cycles CPUID.0xD.15 = 898 cycles CPUID.0xD.16 = 716 cycles CPUID.0xD.17 = 748 cycles CPUID.0xD.18 = 776 cycles Note, updating runtime CPUID information multiple times per nested transition is itself a flaw, especially since CPUID is a mandotory intercept on both Intel and AMD. E.g. KVM doesn't need to ensure emulated CPUID state is up-to-date while running L2. That flaw will be fixed in a future patch, as deferring runtime CPUID updates is more subtle than it appears at first glance, the benefits aren't super critical to have once the XSAVE issue is resolved, and caching CPUID output is desirable even if KVM's updates are deferred. Cc: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20241211013302.1347853-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-12-10Merge tag 'kvmarm-fixes-6.13-2' of ↵Paolo Bonzini
https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.13, part #2 - Fix confusion with implicitly-shifted MDCR_EL2 masks breaking SPE/TRBE initialization - Align nested page table walker with the intended memory attribute combining rules of the architecture - Prevent userspace from constraining the advertised ASID width, avoiding horrors of guest TLBIs not matching the intended context in hardware - Don't leak references on LPIs when insertion into the translation cache fails
2024-12-08Linux 6.13-rc2v6.13-rc2Linus Torvalds
2024-12-08Merge tag 'kbuild-fixes-v6.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - Fix a section mismatch warning in modpost - Fix Debian package build error with the O= option * tag 'kbuild-fixes-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: deb-pkg: fix build error with O= modpost: Add .irqentry.text to OTHER_SECTIONS
2024-12-08Merge tag 'irq_urgent_for_v6.13_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Borislav Petkov: - Fix a /proc/interrupts formatting regression - Have the BCM2836 interrupt controller enter power management states properly - Other fixlets * tag 'irq_urgent_for_v6.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/stm32mp-exti: CONFIG_STM32MP_EXTI should not default to y when compile-testing genirq/proc: Add missing space separator back irqchip/bcm2836: Enable SKIP_SET_WAKE and MASK_ON_SUSPEND irqchip/gic-v3: Fix irq_complete_ack() comment
2024-12-08Merge tag 'timers_urgent_for_v6.13_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Borislav Petkov: - Handle the case where clocksources with small counter width can, in conjunction with overly long idle sleeps, falsely trigger the negative motion detection of clocksources * tag 'timers_urgent_for_v6.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: Make negative motion detection more robust
2024-12-08Merge tag 'x86_urgent_for_v6.13_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Have the Automatic IBRS setting check on AMD does not falsely fire in the guest when it has been set already on the host - Make sure cacheinfo structures memory is allocated to address a boot NULL ptr dereference on Intel Meteor Lake which has different numbers of subleafs in its CPUID(4) leaf - Take care of the GDT restoring on the kexec path too, as expected by the kernel - Make sure SMP is not disabled when IO-APIC is disabled on the kernel cmdline - Add a PGD flag _PAGE_NOPTISHADOW to instruct machinery not to propagate changes to the kernelmode page tables, to the user portion, in PTI - Mark Intel Lunar Lake as affected by an issue where MONITOR wakeups can get lost and thus user-visible delays happen - Make sure PKRU is properly restored with XRSTOR on AMD after a PRKU write of 0 (WRPKRU) which will mark PKRU in its init state and thus lose the actual buffer * tag 'x86_urgent_for_v6.13_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU/AMD: WARN when setting EFER.AUTOIBRS if and only if the WRMSR fails x86/cacheinfo: Delete global num_cache_leaves cacheinfo: Allocate memory during CPU hotplug if not done from the primary CPU x86/kexec: Restore GDT on return from ::preserve_context kexec x86/cpu/topology: Remove limit of CPUs due to disabled IO/APIC x86/mm: Add _PAGE_NOPTISHADOW bit to avoid updating userspace page tables x86/cpu: Add Lunar Lake to list of CPUs with a broken MONITOR implementation x86/pkeys: Ensure updated PKRU value is XRSTOR'd x86/pkeys: Change caller of update_pkru_in_sigframe()
2024-12-08Merge tag 'mm-hotfixes-stable-2024-12-07-22-39' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "24 hotfixes. 17 are cc:stable. 15 are MM and 9 are non-MM. The usual bunch of singletons - please see the relevant changelogs for details" * tag 'mm-hotfixes-stable-2024-12-07-22-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (24 commits) iio: magnetometer: yas530: use signed integer type for clamp limits sched/numa: fix memory leak due to the overwritten vma->numab_state mm/damon: fix order of arguments in damos_before_apply tracepoint lib: stackinit: hide never-taken branch from compiler mm/filemap: don't call folio_test_locked() without a reference in next_uptodate_folio() scatterlist: fix incorrect func name in kernel-doc mm: correct typo in MMAP_STATE() macro mm: respect mmap hint address when aligning for THP mm: memcg: declare do_memsw_account inline mm/codetag: swap tags when migrate pages ocfs2: update seq_file index in ocfs2_dlm_seq_next stackdepot: fix stack_depot_save_flags() in NMI context mm: open-code page_folio() in dump_page() mm: open-code PageTail in folio_flags() and const_folio_flags() mm: fix vrealloc()'s KASAN poisoning logic Revert "readahead: properly shorten readahead when falling back to do_page_cache_ra()" selftests/damon: add _damon_sysfs.py to TEST_FILES selftest: hugetlb_dio: fix test naming ocfs2: free inode when ocfs2_get_init_inode() fails nilfs2: fix potential out-of-bounds memory access in nilfs_find_entry() ...
2024-12-08kbuild: deb-pkg: fix build error with O=Masahiro Yamada
Since commit 13b25489b6f8 ("kbuild: change working directory to external module directory with M="), the Debian package build fails if a relative path is specified with the O= option. $ make O=build bindeb-pkg [ snip ] dpkg-deb: building package 'linux-image-6.13.0-rc1' in '../linux-image-6.13.0-rc1_6.13.0-rc1-6_amd64.deb'. Rebuilding host programs with x86_64-linux-gnu-gcc... make[6]: Entering directory '/home/masahiro/linux/build' /home/masahiro/linux/Makefile:190: *** specified kernel directory "build" does not exist. Stop. This occurs because the sub_make_done flag is cleared, even though the working directory is already in the output directory. Passing KBUILD_OUTPUT=. resolves the issue. Fixes: 13b25489b6f8 ("kbuild: change working directory to external module directory with M=") Reported-by: Charlie Jenkins <charlie@rivosinc.com> Closes: https://lore.kernel.org/all/Z1DnP-GJcfseyrM3@ghost/ Tested-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-12-08modpost: Add .irqentry.text to OTHER_SECTIONSThomas Gleixner
The compiler can fully inline the actual handler function of an interrupt entry into the .irqentry.text entry point. If such a function contains an access which has an exception table entry, modpost complains about a section mismatch: WARNING: vmlinux.o(__ex_table+0x447c): Section mismatch in reference ... The relocation at __ex_table+0x447c references section ".irqentry.text" which is not in the list of authorized sections. Add .irqentry.text to OTHER_SECTIONS to cure the issue. Reported-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org # needed for linux-5.4-y Link: https://lore.kernel.org/all/20241128111844.GE10431@google.com/ Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-12-07Merge tag '6.13-rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull smb client fixes from Steve French: - DFS fix (for race with tree disconnect and dfs cache worker) - Four fixes for SMB3.1.1 posix extensions: - improve special file support e.g. to Samba, retrieving the file type earlier - reduce roundtrips (e.g. on ls -l, in some cases) * tag '6.13-rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: smb: client: fix potential race in cifs_put_tcon() smb3.1.1: fix posix mounts to older servers fs/smb/client: cifs_prime_dcache() for SMB3 POSIX reparse points fs/smb/client: Implement new SMB3 POSIX type fs/smb/client: avoid querying SMB2_OP_QUERY_WSL_EA for SMB3 POSIX
2024-12-07Merge tag 'scsi-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "Large number of small fixes, all in drivers" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (32 commits) scsi: scsi_debug: Fix hrtimer support for ndelay scsi: storvsc: Do not flag MAINTENANCE_IN return of SRB_STATUS_DATA_OVERRUN as an error scsi: ufs: core: Add missing post notify for power mode change scsi: sg: Fix slab-use-after-free read in sg_release() scsi: ufs: core: sysfs: Prevent div by zero scsi: qla2xxx: Update version to 10.02.09.400-k scsi: qla2xxx: Supported speed displayed incorrectly for VPorts scsi: qla2xxx: Fix NVMe and NPIV connect issue scsi: qla2xxx: Remove check req_sg_cnt should be equal to rsp_sg_cnt scsi: qla2xxx: Fix use after free on unload scsi: qla2xxx: Fix abort in bsg timeout scsi: mpi3mr: Update driver version to 8.12.0.3.50 scsi: mpi3mr: Handling of fault code for insufficient power scsi: mpi3mr: Start controller indexing from 0 scsi: mpi3mr: Fix corrupt config pages PHY state is switched in sysfs scsi: mpi3mr: Synchronize access to ioctl data buffer scsi: mpt3sas: Update driver version to 51.100.00.00 scsi: mpt3sas: Diag-Reset when Doorbell-In-Use bit is set during driver load time scsi: ufs: pltfrm: Dellocate HBA during ufshcd_pltfrm_remove() scsi: ufs: pltfrm: Drop PM runtime reference count after ufshcd_remove() ...
2024-12-07Merge tag 'block-6.13-20241207' of git://git.kernel.dk/linuxLinus Torvalds
Pull block fixes from Jens Axboe: - NVMe pull request via Keith: - Target fix using incorrect zero buffer (Nilay) - Device specifc deallocate quirk fixes (Christoph, Keith) - Fabrics fix for handling max command target bugs (Maurizio) - Cocci fix usage for kzalloc (Yu-Chen) - DMA size fix for host memory buffer feature (Christoph) - Fabrics queue cleanup fixes (Chunguang) - CPU hotplug ordering fixes - Add missing MODULE_DESCRIPTION for rnull - bcache error value fix - virtio-blk queue freeze fix * tag 'block-6.13-20241207' of git://git.kernel.dk/linux: blk-mq: move cpuhp callback registering out of q->sysfs_lock blk-mq: register cpuhp callback after hctx is added to xarray table virtio-blk: don't keep queue frozen during system suspend nvme-tcp: simplify nvme_tcp_teardown_io_queues() nvme-tcp: no need to quiesce admin_q in nvme_tcp_teardown_io_queues() nvme-rdma: unquiesce admin_q before destroy it nvme-tcp: fix the memleak while create new ctrl failed nvme-pci: don't use dma_alloc_noncontiguous with 0 merge boundary nvmet: replace kmalloc + memset with kzalloc for data allocation nvme-fabrics: handle zero MAXCMD without closing the connection bcache: revert replacing IS_ERR_OR_NULL with IS_ERR again nvme-pci: remove two deallocate zeroes quirks block: rnull: add missing MODULE_DESCRIPTION nvme: don't apply NVME_QUIRK_DEALLOCATE_ZEROES when DSM is not supported nvmet: use kzalloc instead of ZERO_PAGE in nvme_execute_identify_ns_nvm()
2024-12-07Merge tag 'io_uring-6.13-20241207' of git://git.kernel.dk/linuxLinus Torvalds
Pull io_uring fix from Jens Axboe: "A single fix for a parameter type which affects 32-bit" * tag 'io_uring-6.13-20241207' of git://git.kernel.dk/linux: io_uring: Change res2 parameter type in io_uring_cmd_done
2024-12-07Merge tag 'ubifs-for-linus-6.13-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs Pull jffs2 fix from Richard Weinberger: - Fixup rtime compressor bounds checking * tag 'ubifs-for-linus-6.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs: jffs2: Fix rtime decompressor
2024-12-06Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds
Pull bpf fixes from Daniel Borkmann:: - Fix several issues for BPF LPM trie map which were found by syzbot and during addition of new test cases (Hou Tao) - Fix a missing process_iter_arg register type check in the BPF verifier (Kumar Kartikeya Dwivedi, Tao Lyu) - Fix several correctness gaps in the BPF verifier when interacting with the BPF stack without CAP_PERFMON (Kumar Kartikeya Dwivedi, Eduard Zingerman, Tao Lyu) - Fix OOB BPF map writes when deleting elements for the case of xsk map as well as devmap (Maciej Fijalkowski) - Fix xsk sockets to always clear DMA mapping information when unmapping the pool (Larysa Zaremba) - Fix sk_mem_uncharge logic in tcp_bpf_sendmsg to only uncharge after sent bytes have been finalized (Zijian Zhang) - Fix BPF sockmap with vsocks which was missing a queue check in poll and sockmap cleanup on close (Michal Luczaj) - Fix tools infra to override makefile ARCH variable if defined but empty, which addresses cross-building tools. (Björn Töpel) - Fix two resolve_btfids build warnings on unresolved bpf_lsm symbols (Thomas Weißschuh) - Fix a NULL pointer dereference in bpftool (Amir Mohammadi) - Fix BPF selftests to check for CONFIG_PREEMPTION instead of CONFIG_PREEMPT (Sebastian Andrzej Siewior) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (31 commits) selftests/bpf: Add more test cases for LPM trie selftests/bpf: Move test_lpm_map.c to map_tests bpf: Use raw_spinlock_t for LPM trie bpf: Switch to bpf mem allocator for LPM trie bpf: Fix exact match conditions in trie_get_next_key() bpf: Handle in-place update for full LPM trie correctly bpf: Handle BPF_EXIST and BPF_NOEXIST for LPM trie bpf: Remove unnecessary kfree(im_node) in lpm_trie_update_elem bpf: Remove unnecessary check when updating LPM trie selftests/bpf: Add test for narrow spill into 64-bit spilled scalar selftests/bpf: Add test for reading from STACK_INVALID slots selftests/bpf: Introduce __caps_unpriv annotation for tests bpf: Fix narrow scalar spill onto 64-bit spilled scalar slots bpf: Don't mark STACK_INVALID as STACK_MISC in mark_stack_slot_misc samples/bpf: Remove unnecessary -I flags from libbpf EXTRA_CFLAGS bpf: Zero index arg error string for dynptr and iter selftests/bpf: Add tests for iter arg check bpf: Ensure reg is PTR_TO_STACK in process_iter_arg tools: Override makefile ARCH variable if defined, but empty selftests/bpf: Add apply_bytes test to test_txmsg_redir_wait_sndmem in test_sockmap ...
2024-12-06Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: "Nothing major, some left-overs from the recent merging window (MTE, coco) and some newly found issues like the ptrace() ones. - MTE/hugetlbfs: - Set VM_MTE_ALLOWED in the arch code and remove it from the core code for hugetlbfs mappings - Fix copy_highpage() warning when the source is a huge page but not MTE tagged, taking the wrong small page path - drivers/virt/coco: - Add the pKVM and Arm CCA drivers under the arm64 maintainership - Fix the pkvm driver to fall back to ioremap() (and warn) if the MMIO_GUARD hypercall fails - Keep the Arm CCA driver default 'n' rather than 'm' - A series of fixes for the arm64 ptrace() implementation, potentially leading to the kernel consuming uninitialised stack variables when PTRACE_SETREGSET is invoked with a length of 0 - Fix zone_dma_limit calculation when RAM starts below 4GB and ZONE_DMA is capped to this limit - Fix early boot warning with CONFIG_DEBUG_VIRTUAL=y triggered by a call to page_to_phys() (from patch_map()) which checks pfn_valid() before vmemmap has been set up - Do not clobber bits 15:8 of the ASID used for TTBR1_EL1 and TLBI ops when the kernel assumes 8-bit ASIDs but running under a hypervisor on a system that implements 16-bit ASIDs (found running Linux under Parallels on Apple M4) - ACPI/IORT: Add PMCG platform information for HiSilicon HIP09A as it is using the same SMMU PMCG as HIP09 and suffers from the same errata - Add GCS to cpucap_is_possible(), missed in the recent merge" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: ptrace: fix partial SETREGSET for NT_ARM_GCS arm64: ptrace: fix partial SETREGSET for NT_ARM_POE arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR arm64: ptrace: fix partial SETREGSET for NT_ARM_TAGGED_ADDR_CTRL arm64: cpufeature: Add GCS to cpucap_is_possible() coco: virt: arm64: Do not enable cca guest driver by default arm64: mte: Fix copy_highpage() warning on hugetlb folios arm64: Ensure bits ASID[15:8] are masked out when the kernel uses 8-bit ASIDs ACPI/IORT: Add PMCG platform information for HiSilicon HIP09A MAINTAINERS: Add CCA and pKVM CoCO guest support to the ARM64 entry drivers/virt: pkvm: Don't fail ioremap() call if MMIO_GUARD fails arm64: patching: avoid early page_to_phys() arm64: mm: Fix zone_dma_limit calculation arm64: mte: set VM_MTE_ALLOWED for hugetlbfs at correct place