From patchwork Wed Feb 28 20:35:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 1906015 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4TlR4m3pFVz23qP for ; Thu, 29 Feb 2024 07:38:00 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rfQf9-0005e2-2T; Wed, 28 Feb 2024 15:36:23 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rfQer-0005DQ-3A; Wed, 28 Feb 2024 15:36:05 -0500 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rfQeo-0001Jy-2i; Wed, 28 Feb 2024 15:36:03 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id C815151776; Wed, 28 Feb 2024 23:35:58 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id 5D6958BA7E; Wed, 28 Feb 2024 23:35:22 +0300 (MSK) Received: (nullmailer pid 267641 invoked by uid 1000); Wed, 28 Feb 2024 20:35:21 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Paolo Bonzini , Michael Tokarev Subject: [Stable-7.2.10 44/47] target/i386: remove unnecessary/wrong application of the A20 mask Date: Wed, 28 Feb 2024 23:35:12 +0300 Message-Id: <20240228203521.267565-11-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Paolo Bonzini 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 (cherry picked from commit a28fe7dc1939333c81b895cdced81c69eb7c5ad0) Signed-off-by: Michael Tokarev diff --git a/target/i386/tcg/sysemu/excp_helper.c b/target/i386/tcg/sysemu/excp_helper.c index 389a0d6912..61b8d2fdde 100644 --- a/target/i386/tcg/sysemu/excp_helper.c +++ b/target/i386/tcg/sysemu/excp_helper.c @@ -162,8 +162,7 @@ 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; } @@ -187,8 +186,7 @@ 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; } @@ -208,8 +206,7 @@ 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; } @@ -236,7 +233,7 @@ 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; } @@ -258,8 +255,7 @@ 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; } @@ -285,8 +281,7 @@ 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; } @@ -304,7 +299,7 @@ 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; } @@ -333,7 +328,7 @@ 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; }