Punit Agrawal <punit.agrawal@xxxxxxx> writes:
> KVM only supports PMD hugepages at stage 2. Now that the various page
> handling routines are updated, extend the stage 2 fault handling to
> map in PUD hugepages.
>
> Addition of PUD hugepage support enables additional page sizes (e.g.,
> 1G with 4K granule) which can be useful on cores that support mapping
> larger block sizes in the TLB entries.
>
> Signed-off-by: Punit Agrawal <punit.agrawal@xxxxxxx>
> Cc: Christoffer Dall <christoffer.dall@xxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> Cc: Russell King <linux@xxxxxxxxxxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> ---
>
> v7 -> v7.1
>
> * Added arm helper kvm_stage2_has_pud()
> * Added check for PUD level present at stage 2
> * Dropped redundant comment
> * Fixed up kvm_pud_mkhuge() to complain on arm
>
> arch/arm/include/asm/kvm_mmu.h | 20 +++++
> arch/arm/include/asm/stage2_pgtable.h | 5 ++
> arch/arm64/include/asm/kvm_mmu.h | 16 ++++
> arch/arm64/include/asm/pgtable-hwdef.h | 2 +
> arch/arm64/include/asm/pgtable.h | 2 +
> virt/kvm/arm/mmu.c | 106 +++++++++++++++++++++++--
> 6 files changed, 145 insertions(+), 6 deletions(-)
>
[...]
> diff --git a/arch/arm/include/asm/stage2_pgtable.h b/arch/arm/include/asm/stage2_pgtable.h
> index f6a7ea805232..ec1567d9eb4b 100644
> --- a/arch/arm/include/asm/stage2_pgtable.h
> +++ b/arch/arm/include/asm/stage2_pgtable.h
> @@ -68,4 +68,9 @@ stage2_pmd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
> #define stage2_pmd_table_empty(kvm, pmdp) kvm_page_empty(pmdp)
> #define stage2_pud_table_empty(kvm, pudp) false
>
> +static inline bool kvm_stage2_has_pud(struct kvm *kvm)
> +{
> + return KVM_VTCR_SL0 == VTCR_SL_L1;
> +}
> +
Turns out this isn't quite the right check. On arm32, the maximum number
of supported levels is 3 with LPAE - effectively the helper should
always return false.
I've updated the check locally to key off of CONFIG_PGTABLE_LEVELS. I'll
post these patches later today.
Thanks,
Punit
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
