We rely on the mmu_notifier call backs to handle the split/merge
of huge pages and thus we are guaranteed that, while creating a
block mapping, either the entire block is unmapped at stage2 or it
is missing permission.
However, we miss a case where the block mapping is split for dirty
logging case and then could later be made block mapping, if we cancel the
dirty logging. This not only creates inconsistent TLB entries for
the pages in the the block, but also leakes the table pages for
PMD level.
Handle this corner case for the huge mappings at stage2 by
unmapping the non-huge mapping for the block. This could potentially
release the upper level table. So we need to restart the table walk
once we unmap the range.
Fixes : ad361f093c ("KVM: ARM: Support hugetlbfs backed huge pages")
Reported-by: Zheng Xiang <zhengxiang9@huawei.com>
Cc: Zheng Xiang <zhengxiang9@huawei.com>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
They were missing, and it turns out that we do need them now.
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[ Replace BUG() => WARN_ON(1) for arm32 PUD helpers ]
Signed-off-by: Suzuki Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Right now the stage2 page table for a VM is hard coded, assuming
an IPA of 40bits. As we are about to add support for per VM IPA,
prepare the stage2 page table helpers to accept the kvm instance
to make the right decision for the VM. No functional changes.
Adds stage2_pgd_size(kvm) to replace S2_PGD_SIZE. Also, moves
some of the definitions in arm32 to align with the arm64.
Also drop the _AC() specifier constants wherever possible.
Cc: Christoffer Dall <cdall@kernel.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
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>
Define the page table helpers for walking the stage2 pagetable
for arm. Since both hyp and stage2 have the same number of levels,
as that of the host we reuse the host helpers.
The exceptions are the p.d_addr_end routines which have to deal
with IPA > 32bit, hence we use the open coded version of their host helpers
which supports 64bit.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Suzuki K Poulose