diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2018-09-26 17:32:53 +0100 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2018-10-03 11:45:14 +0100 |
| commit | 58b3efc820acd3219e89ff014e93346a734229b8 (patch) | |
| tree | fd7e6d712ea2f7f759e2d3ee4f2426727cabf1e3 /arch/arm64/kvm/reset.c | |
| parent | 0f62f0e95be29200ab2ab98ca870e22c9b148dfa (diff) | |
| download | linux-stable-58b3efc820acd3219e89ff014e93346a734229b8.tar.gz | |
kvm: arm64: Limit the minimum number of page table levels
Since we are about to remove the lower limit on the IPA size,
make sure that we do not go to 1 level page table (e.g, with
32bit IPA on 64K host with concatenation) to avoid splitting
the host PMD huge pages at stage2.
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <cdall@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm64/kvm/reset.c')
| -rw-r--r-- | arch/arm64/kvm/reset.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index 96b3f50101bc..f156e45760bc 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -190,6 +190,7 @@ int kvm_arm_config_vm(struct kvm *kvm, unsigned long type) { u64 vtcr = VTCR_EL2_FLAGS; u32 parange, phys_shift; + u8 lvls; if (type) return -EINVAL; @@ -203,7 +204,14 @@ int kvm_arm_config_vm(struct kvm *kvm, unsigned long type) if (phys_shift > KVM_PHYS_SHIFT) phys_shift = KVM_PHYS_SHIFT; vtcr |= VTCR_EL2_T0SZ(phys_shift); - vtcr |= VTCR_EL2_LVLS_TO_SL0(stage2_pgtable_levels(phys_shift)); + /* + * Use a minimum 2 level page table to prevent splitting + * host PMD huge pages at stage2. + */ + lvls = stage2_pgtable_levels(phys_shift); + if (lvls < 2) + lvls = 2; + vtcr |= VTCR_EL2_LVLS_TO_SL0(lvls); /* * Enable the Hardware Access Flag management, unconditionally |