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X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org When pKVM is enabled, the host relies on a pkvm_mapping tree that mirrors the actual hypervisor-owned stage-2. The hypervisor is not allowed to silently split blocks or collapse page-tables. This should be treated as a bug. Therefore, WARN on guest stage-2 page-table collapse which would otherwise be fatal anyway. Signed-off-by: Vincent Donnefort diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c index 2340706e41d3..e16dde4c5f4b 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -226,6 +226,12 @@ static void guest_s2_put_page(void *addr) hyp_put_page(¤t_vm->pool, addr); } +static void guest_s2_free_unlinked_table(void *addr, s8 level) +{ + /* We should never collapse guest stage-2 tables into blocks */ + WARN_ON(1); +} + static void __apply_guest_page(void *va, size_t size, void (*func)(void *addr, size_t size)) { @@ -287,6 +293,7 @@ int kvm_guest_prepare_stage2(struct pkvm_hyp_vm *vm, void *pgd) .put_page = guest_s2_put_page, .dcache_clean_inval_poc = clean_dcache_guest_page, .icache_inval_pou = invalidate_icache_guest_page, + .free_unlinked_table = guest_s2_free_unlinked_table, }; guest_lock_component(vm); -- 2.55.0.508.g3f0d502094-goog