diff options
| author | Marc Zyngier <maz@kernel.org> | 2021-07-26 18:35:49 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-08-02 16:05:58 +0300 |
| commit | f2cc327303b13a70311e823bd52aa0bca8c7ddbc (patch) | |
| tree | 2356bc2c3a50d2618f84f99fadeba59ae07d8da7 /arch/arm64/kvm/mmu.c | |
| parent | 6011cf68c88545e16cb32039c2cecfdae6a32315 (diff) | |
| download | linux-f2cc327303b13a70311e823bd52aa0bca8c7ddbc.tar.xz | |
KVM: arm64: Avoid mapping size adjustment on permission fault
Since we only support PMD-sized mappings for THP, getting
a permission fault on a level that results in a mapping
being larger than PAGE_SIZE is a sure indication that we have
already upgraded our mapping to a PMD.
In this case, there is no need to try and parse userspace page
tables, as the fault information already tells us everything.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20210726153552.1535838-4-maz@kernel.org
Diffstat (limited to 'arch/arm64/kvm/mmu.c')
| -rw-r--r-- | arch/arm64/kvm/mmu.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 183c107c06b2..116a2910a4a4 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1076,9 +1076,14 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, * If we are not forced to use page mapping, check if we are * backed by a THP and thus use block mapping if possible. */ - if (vma_pagesize == PAGE_SIZE && !(force_pte || device)) - vma_pagesize = transparent_hugepage_adjust(kvm, memslot, hva, - &pfn, &fault_ipa); + if (vma_pagesize == PAGE_SIZE && !(force_pte || device)) { + if (fault_status == FSC_PERM && fault_granule > PAGE_SIZE) + vma_pagesize = fault_granule; + else + vma_pagesize = transparent_hugepage_adjust(kvm, memslot, + hva, &pfn, + &fault_ipa); + } if (fault_status != FSC_PERM && !device && kvm_has_mte(kvm)) { /* Check the VMM hasn't introduced a new VM_SHARED VMA */ |