diff options
| author | Quentin Perret <qperret@google.com> | 2021-03-19 10:01:41 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-03-19 12:01:22 +0000 |
| commit | 8942a237c771b65f8bc1232536e4b4b829c7701f (patch) | |
| tree | c19641aba486d05beccbea58cec09c600473f883 /arch | |
| parent | bc224df155c466178128a2950af16cba37b6f218 (diff) | |
KVM: arm64: Introduce KVM_PGTABLE_S2_IDMAP stage 2 flag
Introduce a new stage 2 configuration flag to specify that all mappings
in a given page-table will be identity-mapped, as will be the case for
the host. This allows to introduce sanity checks in the map path and to
avoid programming errors.
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210319100146.1149909-34-qperret@google.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/kvm_pgtable.h | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/pgtable.c | 3 |
2 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 55452f4831d2..c3674c47d48c 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -60,9 +60,11 @@ struct kvm_pgtable_mm_ops { * enum kvm_pgtable_stage2_flags - Stage-2 page-table flags. * @KVM_PGTABLE_S2_NOFWB: Don't enforce Normal-WB even if the CPUs have * ARM64_HAS_STAGE2_FWB. + * @KVM_PGTABLE_S2_IDMAP: Only use identity mappings. */ enum kvm_pgtable_stage2_flags { KVM_PGTABLE_S2_NOFWB = BIT(0), + KVM_PGTABLE_S2_IDMAP = BIT(1), }; /** diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index b22b4860630c..c37c1dc4feaf 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -760,6 +760,9 @@ int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, .arg = &map_data, }; + if (WARN_ON((pgt->flags & KVM_PGTABLE_S2_IDMAP) && (addr != phys))) + return -EINVAL; + ret = stage2_set_prot_attr(pgt, prot, &map_data.attr); if (ret) return ret; |