This series adds support for using the Arm Memory Tagging Extensions (MTE) in a KVM guest. Changes since v12[1]: * Use DEFINE_SPINLOCK() to define tag_sync_lock. * Refactor mte_sync_tags() to take the old PTE value rather than a pointer to the PTE. The checks in set_pte_at() are also strengthed to avoid the function call when possible. * Fix prefix on a couple of patches ("arm64: kvm" -> "KVM: arm64"). * Reorder arguments to sanitise_mte_tags() ("size, pfn" -> "pfn, size"). * Add/improve comments in several places. * Report the host's sanitised version of ID_AA64PFR1_EL1:MTE rather than making up one for the guest. * Insert ISB at the end of mte_switch_to_hyp macro. * Drop the definition of CPU_TFSRE0_EL1 in asm-offsets.c as it isn't used anymore. * Prevent creation of 32 bit vCPUs when MTE is enabled for the guest (and document it). * Move kvm_vm_ioctl_mte_copy_tags() to guest.c. * Reject ZONE_DEVICE memory in kvm_vm_ioctl_mte_copy_tags() and correctly handle pages where PG_mte_tagged hasn't been set yet. * Define MTE_GRANULES_PER_PAGE rather than open coding the divison PAGE_SIZE / MTE_GRANULE_SIZE. * Correct the definition of struct kvm_arm_copy_mte_tags in the docs. Also avoid mentioning MTE_GRANULE_SIZE as it isn't exported to userspace. [1] https://lore.kernel.org/r/20210517123239.8025-1-steven.price@xxxxxxx/ Catalin Marinas (1): arm64: Handle MTE tags zeroing in __alloc_zeroed_user_highpage() Steven Price (7): arm64: mte: Handle race when synchronising tags arm64: mte: Sync tags for pages where PTE is untagged KVM: arm64: Introduce MTE VM feature KVM: arm64: Save/restore MTE registers KVM: arm64: Expose KVM_ARM_CAP_MTE KVM: arm64: ioctl to fetch/store tags in a guest KVM: arm64: Document MTE capability and ioctl Documentation/virt/kvm/api.rst | 52 ++++++++++++++ arch/arm64/include/asm/kvm_emulate.h | 3 + arch/arm64/include/asm/kvm_host.h | 12 ++++ arch/arm64/include/asm/kvm_mte.h | 68 +++++++++++++++++++ arch/arm64/include/asm/mte-def.h | 1 + arch/arm64/include/asm/mte.h | 4 +- arch/arm64/include/asm/page.h | 6 +- arch/arm64/include/asm/pgtable.h | 22 +++++- arch/arm64/include/asm/sysreg.h | 3 +- arch/arm64/include/uapi/asm/kvm.h | 11 +++ arch/arm64/kernel/asm-offsets.c | 2 + arch/arm64/kernel/mte.c | 37 ++++++++-- arch/arm64/kvm/arm.c | 16 +++++ arch/arm64/kvm/guest.c | 79 ++++++++++++++++++++++ arch/arm64/kvm/hyp/entry.S | 7 ++ arch/arm64/kvm/hyp/exception.c | 3 +- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 21 ++++++ arch/arm64/kvm/mmu.c | 48 ++++++++++++- arch/arm64/kvm/reset.c | 3 +- arch/arm64/kvm/sys_regs.c | 32 +++++++-- arch/arm64/mm/fault.c | 21 ++++++ include/uapi/linux/kvm.h | 2 + 22 files changed, 431 insertions(+), 22 deletions(-) create mode 100644 arch/arm64/include/asm/kvm_mte.h -- 2.20.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm