diff options
Diffstat (limited to 'Documentation/virt')
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 27 | ||||
| -rw-r--r-- | Documentation/virt/kvm/x86/amd-memory-encryption.rst | 2 | ||||
| -rw-r--r-- | Documentation/virt/kvm/x86/mmu.rst | 2 |
3 files changed, 29 insertions, 2 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 96c4475539c2..c0ddd3035462 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -8445,6 +8445,33 @@ structure. When getting the Modified Change Topology Report value, the attr->addr must point to a byte where the value will be stored or retrieved from. +8.40 KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE +--------------------------------------- + +:Capability: KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE +:Architectures: arm64 +:Type: vm +:Parameters: arg[0] is the new split chunk size. +:Returns: 0 on success, -EINVAL if any memslot was already created. + +This capability sets the chunk size used in Eager Page Splitting. + +Eager Page Splitting improves the performance of dirty-logging (used +in live migrations) when guest memory is backed by huge-pages. It +avoids splitting huge-pages (into PAGE_SIZE pages) on fault, by doing +it eagerly when enabling dirty logging (with the +KVM_MEM_LOG_DIRTY_PAGES flag for a memory region), or when using +KVM_CLEAR_DIRTY_LOG. + +The chunk size specifies how many pages to break at a time, using a +single allocation for each chunk. Bigger the chunk size, more pages +need to be allocated ahead of time. + +The chunk size needs to be a valid block size. The list of acceptable +block sizes is exposed in KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES as a +64-bit bitmap (each bit describing a block size). The default value is +0, to disable the eager page splitting. + 9. Known KVM API problems ========================= diff --git a/Documentation/virt/kvm/x86/amd-memory-encryption.rst b/Documentation/virt/kvm/x86/amd-memory-encryption.rst index 487b6328b3e7..995780088eb2 100644 --- a/Documentation/virt/kvm/x86/amd-memory-encryption.rst +++ b/Documentation/virt/kvm/x86/amd-memory-encryption.rst @@ -57,7 +57,7 @@ information, see the SEV Key Management spec [api-spec]_ The main ioctl to access SEV is KVM_MEMORY_ENCRYPT_OP. If the argument to KVM_MEMORY_ENCRYPT_OP is NULL, the ioctl returns 0 if SEV is enabled -and ``ENOTTY` if it is disabled (on some older versions of Linux, +and ``ENOTTY`` if it is disabled (on some older versions of Linux, the ioctl runs normally even with a NULL argument, and therefore will likely return ``EFAULT``). If non-NULL, the argument to KVM_MEMORY_ENCRYPT_OP must be a struct kvm_sev_cmd:: diff --git a/Documentation/virt/kvm/x86/mmu.rst b/Documentation/virt/kvm/x86/mmu.rst index 8364afa228ec..26f62034b6f3 100644 --- a/Documentation/virt/kvm/x86/mmu.rst +++ b/Documentation/virt/kvm/x86/mmu.rst @@ -205,7 +205,7 @@ Shadow pages contain the following information: role.passthrough: The page is not backed by a guest page table, but its first entry points to one. This is set if NPT uses 5-level page tables (host - CR4.LA57=1) and is shadowing L1's 4-level NPT (L1 CR4.LA57=1). + CR4.LA57=1) and is shadowing L1's 4-level NPT (L1 CR4.LA57=0). gfn: Either the guest page table containing the translations shadowed by this page, or the base page frame for linear translations. See role.direct. |