[4.9,160/222] kvm: arm/arm64: Fix stage2_flush_memslot for 4 level page table

Message ID 20191122100914.210051442@linuxfoundation.org
State New
Headers show
Series
  • Untitled series #25170
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Commit Message

Greg KH Nov. 22, 2019, 10:28 a.m.
From: Suzuki K Poulose <suzuki.poulose@arm.com>


[ Upstream commit d2db7773ba864df6b4e19643dfc54838550d8049 ]

So far we have only supported 3 level page table with fixed IPA of
40bits, where PUD is folded. With 4 level page tables, we need
to check if the PUD entry is valid or not. Fix stage2_flush_memslot()
to do this check, before walking down the table.

Acked-by: 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>

Signed-off-by: Sasha Levin <sashal@kernel.org>

---
 arch/arm/kvm/mmu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

-- 
2.20.1

Patch

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index b3d268a79f057..bb0d5e21d60bd 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -366,7 +366,8 @@  static void stage2_flush_memslot(struct kvm *kvm,
 	pgd = kvm->arch.pgd + stage2_pgd_index(addr);
 	do {
 		next = stage2_pgd_addr_end(addr, end);
-		stage2_flush_puds(kvm, pgd, addr, next);
+		if (!stage2_pgd_none(*pgd))
+			stage2_flush_puds(kvm, pgd, addr, next);
 	} while (pgd++, addr = next, addr != end);
 }