This series adds support for using the Arm Memory Tagging Extensions (MTE) in a KVM guest.
Changes since v13[1]: * Add Reviewed-by tags from Catalin - thanks! * Introduce a new function mte_prepare_page_tags() for handling the initialisation of pages ready for a KVM guest. This takes the big tag_sync_lock removing any race with the VMM (or another guest) around clearing the tags and setting PG_mte_tagged. * The ioctl to fetch/store tags now returns the number of bytes processed so userspace can tell how far a partial fetch/store got. * Some minor refactoring to tidy up the code thanks to pointers from Catalin. [1] https://lore.kernel.org/r/20210524104513.13258-1-steven.price%40arm.com 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 | 57 +++++++++++++++ arch/arm64/include/asm/kvm_arm.h | 3 +- arch/arm64/include/asm/kvm_emulate.h | 3 + arch/arm64/include/asm/kvm_host.h | 12 ++++ arch/arm64/include/asm/kvm_mte.h | 66 +++++++++++++++++ arch/arm64/include/asm/mte-def.h | 1 + arch/arm64/include/asm/mte.h | 8 ++- 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 | 54 ++++++++++++-- arch/arm64/kvm/arm.c | 16 +++++ arch/arm64/kvm/guest.c | 82 ++++++++++++++++++++++ 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 | 42 ++++++++++- 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 + 23 files changed, 454 insertions(+), 23 deletions(-) create mode 100644 arch/arm64/include/asm/kvm_mte.h -- 2.20.1
