Commit 3fb884ff authored by Marc Zyngier's avatar Marc Zyngier

KVM: arm64: Do not try to map PUDs when they are folded into PMD

For the obscure cases where PMD and PUD are the same size
(64kB pages with 42bit VA, for example, which results in only
two levels of page tables), we can't map anything as a PUD,
because there is... erm... no PUD to speak of. Everything is
either a PMD or a PTE.

So let's only try and map a PUD when its size is different from
that of a PMD.

Cc: stable@vger.kernel.org
Fixes: b8e0ba7c ("KVM: arm64: Add support for creating PUD hugepages at stage 2")
Reported-by: default avatarGavin Shan <gshan@redhat.com>
Reported-by: default avatarEric Auger <eric.auger@redhat.com>
Reviewed-by: default avatarAlexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
Tested-by: default avatarGavin Shan <gshan@redhat.com>
Tested-by: default avatarEric Auger <eric.auger@redhat.com>
Tested-by: default avatarAlexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 004a0124
...@@ -1964,7 +1964,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, ...@@ -1964,7 +1964,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
(fault_status == FSC_PERM && (fault_status == FSC_PERM &&
stage2_is_exec(mmu, fault_ipa, vma_pagesize)); stage2_is_exec(mmu, fault_ipa, vma_pagesize));
if (vma_pagesize == PUD_SIZE) { /*
* If PUD_SIZE == PMD_SIZE, there is no real PUD level, and
* all we have is a 2-level page table. Trying to map a PUD in
* this case would be fatally wrong.
*/
if (PUD_SIZE != PMD_SIZE && vma_pagesize == PUD_SIZE) {
pud_t new_pud = kvm_pfn_pud(pfn, mem_type); pud_t new_pud = kvm_pfn_pud(pfn, mem_type);
new_pud = kvm_pud_mkhuge(new_pud); new_pud = kvm_pud_mkhuge(new_pud);
......
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