kernel/linux.git/arch/arm64/include/asm/cpu.h, branch v6.12.80

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2024-03-15T20:03:13+00:00

Pull kvm updates from Paolo Bonzini: "S390: - Changes to FPU handling came in via the main s390 pull request - Only deliver to the guest the SCLP events that userspace has requested - More virtual vs physical address fixes (only a cleanup since virtual and physical address spaces are currently the same) - Fix selftests undefined behavior x86: - Fix a restriction that the guest can't program a PMU event whose encoding matches an architectural event that isn't included in the guest CPUID. The enumeration of an architectural event only says that if a CPU supports an architectural event, then the event can be programmed *using the architectural encoding*. The enumeration does NOT say anything about the encoding when the CPU doesn't report support the event *in general*. It might support it, and it might support it using the same encoding that made it into the architectural PMU spec - Fix a variety of bugs in KVM's emulation of RDPMC (more details on individual commits) and add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID and therefore are easier to validate with selftests than with custom guests (aka kvm-unit-tests) - Zero out PMU state on AMD if the virtual PMU is disabled, it does not cause any bug but it wastes time in various cases where KVM would check if a PMC event needs to be synthesized - Optimize triggering of emulated events, with a nice ~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 - Fix a bug where KVM would report stale/bogus exit qualification information when exiting to userspace with an internal error exit code - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support - Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for read, e.g. to avoid serializing vCPUs when userspace deletes a memslot - Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB). KVM doesn't support yielding in the middle of processing a zap, and 1GiB granularity resulted in multi-millisecond lags that are quite impolite for CONFIG_PREEMPT kernels - Allocate write-tracking metadata on-demand to avoid the memory overhead when a kernel is built with i915 virtualization support but the workloads use neither shadow paging nor i915 virtualization - Explicitly initialize a variety of on-stack variables in the emulator that triggered KMSAN false positives - Fix the debugregs ABI for 32-bit KVM - Rework the "force immediate exit" code so that vendor code ultimately decides how and when to force the exit, which allowed some optimization for both Intel and AMD - Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if vCPU creation ultimately failed, causing extra unnecessary work - Cleanup the logic for checking if the currently loaded vCPU is in-kernel - Harden against underflowing the active mmu_notifier invalidation count, so that "bad" invalidations (usually due to bugs elsehwere in the kernel) are detected earlier and are less likely to hang the kernel x86 Xen emulation: - Overlay pages can now be cached based on host virtual address, instead of guest physical addresses. This removes the need to reconfigure and invalidate the cache if the guest changes the gpa but the underlying host virtual address remains the same - When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation - Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior) - Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs RISC-V: - Support exception and interrupt handling in selftests - New self test for RISC-V architectural timer (Sstc extension) - New extension support (Ztso, Zacas) - Support userspace emulation of random number seed CSRs ARM: - Infrastructure for building KVM's trap configuration based on the architectural features (or lack thereof) advertised in the VM's ID registers - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to x86's WC) at stage-2, improving the performance of interacting with assigned devices that can tolerate it - Conversion of KVM's representation of LPIs to an xarray, utilized to address serialization some of the serialization on the LPI injection path - Support for _architectural_ VHE-only systems, advertised through the absence of FEAT_E2H0 in the CPU's ID register - Miscellaneous cleanups, fixes, and spelling corrections to KVM and selftests LoongArch: - Set reserved bits as zero in CPUCFG - Start SW timer only when vcpu is blocking - Do not restart SW timer when it is expired - Remove unnecessary CSR register saving during enter guest - Misc cleanups and fixes as usual Generic: - Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically always true on all architectures except MIPS (where Kconfig determines the available depending on CPU capabilities). It is replaced either by an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM) everywhere else - Factor common "select" statements in common code instead of requiring each architecture to specify it - Remove thoroughly obsolete APIs from the uapi headers - Move architecture-dependent stuff to uapi/asm/kvm.h - Always flush the async page fault workqueue when a work item is being removed, especially during vCPU destruction, to ensure that there are no workers running in KVM code when all references to KVM-the-module are gone, i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded - Grab a reference to the VM's mm_struct in the async #PF worker itself instead of gifting the worker a reference, so that there's no need to remember to *conditionally* clean up after the worker Selftests: - Reduce boilerplate especially when utilize selftest TAP infrastructure - Add basic smoke tests for SEV and SEV-ES, along with a pile of library support for handling private/encrypted/protected memory - Fix benign bugs where tests neglect to close() guest_memfd files" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits) selftests: kvm: remove meaningless assignments in Makefiles KVM: riscv: selftests: Add Zacas extension to get-reg-list test RISC-V: KVM: Allow Zacas extension for Guest/VM KVM: riscv: selftests: Add Ztso extension to get-reg-list test RISC-V: KVM: Allow Ztso extension for Guest/VM RISC-V: KVM: Forward SEED CSR access to user space KVM: riscv: selftests: Add sstc timer test KVM: riscv: selftests: Change vcpu_has_ext to a common function KVM: riscv: selftests: Add guest helper to get vcpu id KVM: riscv: selftests: Add exception handling support LoongArch: KVM: Remove unnecessary CSR register saving during enter guest LoongArch: KVM: Do not restart SW timer when it is expired LoongArch: KVM: Start SW timer only when vcpu is blocking LoongArch: KVM: Set reserved bits as zero in CPUCFG KVM: selftests: Explicitly close guest_memfd files in some gmem tests KVM: x86/xen: fix recursive deadlock in timer injection KVM: pfncache: simplify locking and make more self-contained KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled KVM: x86/xen: improve accuracy of Xen timers ...

arm64/cpufeature: Hook new identification registers up to cpufeature

2024-03-07T17:14:52+00:00

The 2023 architecture extensions have defined several new ID registers, hook them up to the cpufeature code so we can add feature checks and hwcaps based on their contents. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-1-c568edc8ed7f@kernel.org Signed-off-by: Catalin Marinas

arm64: cpufeature: Add ID_AA64MMFR4_EL1 handling

2024-02-08T15:12:45+00:00

Add ID_AA64MMFR4_EL1 to the list of idregs the kernel knows about, and describe the E2H0 field. Reviewed-by: Oliver Upton Reviewed-by: Suzuki K Poulose Signed-off-by: Marc Zyngier Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20240122181344.258974-6-maz@kernel.org Signed-off-by: Oliver Upton

arm64: setup: Switch over to GENERIC_CPU_DEVICES using arch_register_cpu()

2023-12-06T03:41:49+00:00

To allow ACPI's _STA value to hide CPUs that are present, but not available to online right now due to VMM or firmware policy, the register_cpu() call needs to be made by the ACPI machinery when ACPI is in use. This allows it to hide CPUs that are unavailable from sysfs. Switching to GENERIC_CPU_DEVICES is an intermediate step to allow all five ACPI architectures to be modified at once. Switch over to GENERIC_CPU_DEVICES, and provide an arch_register_cpu() that populates the hotpluggable flag. arch_register_cpu() is also the interface the ACPI machinery expects. The struct cpu in struct cpuinfo_arm64 is never used directly, remove it to use the one GENERIC_CPU_DEVICES provides. This changes the CPUs visible in sysfs from possible to present, but on arm64 smp_prepare_cpus() ensures these are the same. This patch also has the effect of moving the registration of CPUs from subsys to driver core initialisation, prior to any initcalls running. Signed-off-by: James Morse Reviewed-by: "Russell King (Oracle)" Reviewed-by: Shaoqin Huang Reviewed-by: Gavin Shan Signed-off-by: "Russell King (Oracle)" Reviewed-by: Jonathan Cameron Reviewed-by: Thomas Gleixner Link: https://lore.kernel.org/r/E1r5R3b-00Csza-Ku@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman

arm64/sve: Remove SMCR pseudo register from cpufeature code

2023-09-25T15:14:49+00:00

For reasons that are not currently apparent during cpufeature enumeration we maintain a pseudo register for SMCR which records the maximum supported vector length using the value that would be written to SMCR_EL1.LEN to configure it. This is not exposed to userspace and is not sufficient for detecting unsupportable configurations, we need the more detailed checks in vec_update_vq_map() for that since we can't cope with missing vector lengths on late CPUs and KVM requires an exactly matching set of supported vector lengths as EL1 can enumerate VLs directly with the hardware. Remove the code, replacing the usage in sme_setup() with a query of the vq_map. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230913-arm64-vec-len-cpufeature-v1-2-cc69b0600a8a@kernel.org Signed-off-by: Catalin Marinas

arm64/sve: Remove ZCR pseudo register from cpufeature code

2023-09-25T15:14:49+00:00

For reasons that are not currently apparent during cpufeature enumeration we maintain a pseudo register for ZCR which records the maximum supported vector length using the value that would be written to ZCR_EL1.LEN to configure it. This is not exposed to userspace and is not sufficient for detecting unsupportable configurations, we need the more detailed checks in vec_update_vq_map() for that since we can't cope with missing vector lengths on late CPUs and KVM requires an exactly matching set of supported vector lengths as EL1 can enumerate VLs directly with the hardware. Remove the code, replacing the usage in sve_setup() with a query of the vq_map. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230913-arm64-vec-len-cpufeature-v1-1-cc69b0600a8a@kernel.org Signed-off-by: Catalin Marinas

arm64: cpufeature: add system register ID_AA64MMFR3

2023-06-06T15:52:40+00:00

Add new system register ID_AA64MMFR3 to the cpufeature infrastructure. Signed-off-by: Joey Gouly Cc: Will Deacon Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20230606145859.697944-6-joey.gouly@arm.com Signed-off-by: Catalin Marinas

arm64/sme: Expose SMIDR through sysfs

2022-06-23T17:22:44+00:00

We currently expose MIDR and REVID to userspace through sysfs to enable it to make decisions based on the specific implementation. Since SME supports implementations where streaming mode is provided by a separate hardware unit called a SMCU it provides a similar ID register SMIDR. Expose it to userspace via sysfs when the system supports SME along with the other ID registers. Since we disable the SME priority mapping feature if it is supported by hardware we currently mask out the SMPS bit which reports that it is supported. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20220607132857.1358361-1-broonie@kernel.org Signed-off-by: Will Deacon

arm64/sme: Identify supported SME vector lengths at boot

2022-04-22T17:50:51+00:00

The vector lengths used for SME are controlled through a similar set of registers to those for SVE and enumerated using a similar algorithm with some slight differences due to the fact that unlike SVE there are no restrictions on which combinations of vector lengths can be supported nor any mandatory vector lengths which must be implemented. Add a new vector type and implement support for enumerating it. One slightly awkward feature is that we need to read the current vector length using a different instruction (or enter streaming mode which would have the same issue and be higher cost). Rather than add an ops structure we add special cases directly in the otherwise generic vec_probe_vqs() function, this is a bit inelegant but it's the only place where this is an issue. Signed-off-by: Mark Brown Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20220419112247.711548-10-broonie@kernel.org Signed-off-by: Catalin Marinas

arm64/sme: Basic enumeration support

2022-04-22T17:50:49+00:00

This patch introduces basic cpufeature support for discovering the presence of the Scalable Matrix Extension. Signed-off-by: Mark Brown Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20220419112247.711548-9-broonie@kernel.org Signed-off-by: Catalin Marinas