[PATCH 6.1.y] KVM: arm64: Don't pass a TLBI level hint when zapping table entries

[PATCH 6.1.y] KVM: arm64: Don't pass a TLBI level hint when zapping table entries

[Will Deacon]

commit 36e008323926036650299cfbb2dca704c7aba849 upstream.

The TLBI level hints are for leaf entries only, so take care not to pass
them incorrectly after clearing a table entry.

Cc: Gavin Shan <gshan@redhat.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Fixes: 82bb02445de5 ("KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2")
Fixes: 6d9d2115c480 ("KVM: arm64: Add support for stage-2 map()/unmap() in generic page-table")
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240327124853.11206-3-will@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Cc: <stable@vger.kernel.org> # 6.1.y only
[will@: Use '0' instead of TLBI_TTL_UNKNOWN_to indicate "no level". Force
        level to 0 in stage2_put_pte() if we're clearing a table entry.]
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kvm/hyp/pgtable.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index ae5f6b5ac80f..f0167dc7438f 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -475,7 +475,7 @@ static int hyp_unmap_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
 
 		kvm_clear_pte(ptep);
 		dsb(ishst);
-		__tlbi_level(vae2is, __TLBI_VADDR(addr, 0), level);
+		__tlbi_level(vae2is, __TLBI_VADDR(addr, 0), 0);
 	} else {
 		if (end - addr < granule)
 			return -EINVAL;
@@ -699,8 +699,14 @@ static void stage2_put_pte(kvm_pte_t *ptep, struct kvm_s2_mmu *mmu, u64 addr,
 	 * Clear the existing PTE, and perform break-before-make with
 	 * TLB maintenance if it was valid.
 	 */
-	if (kvm_pte_valid(*ptep)) {
+	kvm_pte_t pte = *ptep;
+
+	if (kvm_pte_valid(pte)) {
 		kvm_clear_pte(ptep);
+
+		if (kvm_pte_table(pte, level))
+			level = 0;
+
 		kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, addr, level);
 	}
 
-- 
2.46.0.184.g6999bdac58-goog