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envelope-from=pbonzini@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.088, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org If ptw_translate() does a MMU_PHYS_IDX access, the A20 mask is already applied in get_physical_address(), which is called via probe_access_full() and x86_cpu_tlb_fill(). If ptw_translate() on the other hand does a MMU_NESTED_IDX access, the A20 mask must not be applied to the address that is looked up in the nested page tables; it must be applied only to the addresses that hold the NPT entries (which is achieved via MMU_PHYS_IDX, per the previous paragraph). Therefore, we can remove A20 masking from the computation of the page table entry's address, and let get_physical_address() or mmu_translate() apply it when they know they are returning a host-physical address. Cc: qemu-stable@nongnu.org Fixes: 4a1e9d4d11c ("target/i386: Use atomic operations for pte updates", 2022-10-18) Signed-off-by: Paolo Bonzini --- target/i386/tcg/sysemu/excp_helper.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/target/i386/tcg/sysemu/excp_helper.c b/target/i386/tcg/sysemu/excp_helper.c index 8bcdd2906d5..2ddc08b4bb6 100644 --- a/target/i386/tcg/sysemu/excp_helper.c +++ b/target/i386/tcg/sysemu/excp_helper.c @@ -164,8 +164,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 5 */ - pte_addr = ((in->cr3 & ~0xfff) + - (((addr >> 48) & 0x1ff) << 3)) & a20_mask; + pte_addr = (in->cr3 & ~0xfff) + (((addr >> 48) & 0x1ff) << 3); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -189,8 +188,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 4 */ - pte_addr = ((pte & PG_ADDRESS_MASK) + - (((addr >> 39) & 0x1ff) << 3)) & a20_mask; + pte_addr = (pte & PG_ADDRESS_MASK) + (((addr >> 39) & 0x1ff) << 3); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -210,8 +208,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 3 */ - pte_addr = ((pte & PG_ADDRESS_MASK) + - (((addr >> 30) & 0x1ff) << 3)) & a20_mask; + pte_addr = (pte & PG_ADDRESS_MASK) + (((addr >> 30) & 0x1ff) << 3); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -238,7 +235,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 3 */ - pte_addr = ((in->cr3 & 0xffffffe0ULL) + ((addr >> 27) & 0x18)) & a20_mask; + pte_addr = (in->cr3 & 0xffffffe0ULL) + ((addr >> 27) & 0x18); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -260,8 +257,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 2 */ - pte_addr = ((pte & PG_ADDRESS_MASK) + - (((addr >> 21) & 0x1ff) << 3)) & a20_mask; + pte_addr = (pte & PG_ADDRESS_MASK) + (((addr >> 21) & 0x1ff) << 3); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -287,8 +283,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 1 */ - pte_addr = ((pte & PG_ADDRESS_MASK) + - (((addr >> 12) & 0x1ff) << 3)) & a20_mask; + pte_addr = (pte & PG_ADDRESS_MASK) + (((addr >> 12) & 0x1ff) << 3); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -306,7 +301,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 2 */ - pte_addr = ((in->cr3 & 0xfffff000ULL) + ((addr >> 20) & 0xffc)) & a20_mask; + pte_addr = (in->cr3 & 0xfffff000ULL) + ((addr >> 20) & 0xffc); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } @@ -335,7 +330,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in, /* * Page table level 1 */ - pte_addr = ((pte & ~0xfffu) + ((addr >> 10) & 0xffc)) & a20_mask; + pte_addr = (pte & ~0xfffu) + ((addr >> 10) & 0xffc); if (!ptw_translate(&pte_trans, pte_addr)) { return false; }