From 3a0b870e3448302ca2ba703bea1b79b61c3f33c6 Mon Sep 17 00:00:00 2001 From: Yanan Wang Date: Wed, 2 Dec 2020 04:10:33 +0800 Subject: [PATCH] KVM: arm64: Fix handling of merging tables into a block entry When dirty logging is enabled, we collapse block entries into tables as necessary. If dirty logging gets canceled, we can end-up merging tables back into block entries. When this happens, we must not only free the non-huge page-table pages but also invalidate all the TLB entries that can potentially cover the block. Otherwise, we end-up with multiple possible translations for the same physical page, which can legitimately result in a TLB conflict. To address this, replease the bogus invalidation by IPA with a full VM invalidation. Although this is pretty heavy handed, it happens very infrequently and saves a bunch of invalidations by IPA. Signed-off-by: Yanan Wang [maz: fixup commit message] Signed-off-by: Marc Zyngier Acked-by: Will Deacon Link: https://lore.kernel.org/r/20201201201034.116760-3-wangyanan55@huawei.com --- arch/arm64/kvm/hyp/pgtable.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 2beba1dc40ec..bdf8e55ed308 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -502,7 +502,13 @@ static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level, return 0; kvm_set_invalid_pte(ptep); - kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, 0); + + /* + * Invalidate the whole stage-2, as we may have numerous leaf + * entries below us which would otherwise need invalidating + * individually. + */ + kvm_call_hyp(__kvm_tlb_flush_vmid, data->mmu); data->anchor = ptep; return 0; } -- 2.11.0