From nobody Tue Nov 26 08:45:39 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1709161039558330.2875527434062; Wed, 28 Feb 2024 14:57:19 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rfSqO-000665-Sj; Wed, 28 Feb 2024 17:56:09 -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 1rfSq8-0005qT-Ls; Wed, 28 Feb 2024 17:55:54 -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 1rfSq6-0000n0-4D; Wed, 28 Feb 2024 17:55:52 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 5432B51813; Thu, 29 Feb 2024 01:55:33 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id B818E8BB46; Thu, 29 Feb 2024 01:54:56 +0300 (MSK) Received: (nullmailer pid 274155 invoked by uid 1000); Wed, 28 Feb 2024 22:54:55 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Paolo Bonzini , Michael Tokarev Subject: [Stable-8.2.2 74/78] target/i386: remove unnecessary/wrong application of the A20 mask Date: Thu, 29 Feb 2024 01:54:50 +0300 Message-Id: <20240228225455.274062-14-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; 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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1709161040048100001 Content-Type: text/plain; charset="utf-8" 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", 2= 022-10-18) 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 38c313abc9..89df61eec6 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 Trans= lateParams *in, /* * Page table level 5 */ - pte_addr =3D ((in->cr3 & ~0xfff) + - (((addr >> 48) & 0x1ff) << 3)) & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 4 */ - pte_addr =3D ((pte & PG_ADDRESS_MASK) + - (((addr >> 39) & 0x1ff) << 3)) & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 3 */ - pte_addr =3D ((pte & PG_ADDRESS_MASK) + - (((addr >> 30) & 0x1ff) << 3)) & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 3 */ - pte_addr =3D ((in->cr3 & 0xffffffe0ULL) + ((addr >> 27) & 0x18= )) & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 2 */ - pte_addr =3D ((pte & PG_ADDRESS_MASK) + - (((addr >> 21) & 0x1ff) << 3)) & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 1 */ - pte_addr =3D ((pte & PG_ADDRESS_MASK) + - (((addr >> 12) & 0x1ff) << 3)) & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 2 */ - pte_addr =3D ((in->cr3 & 0xfffff000ULL) + ((addr >> 20) & 0xffc)) = & a20_mask; + pte_addr =3D (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 Trans= lateParams *in, /* * Page table level 1 */ - pte_addr =3D ((pte & ~0xfffu) + ((addr >> 10) & 0xffc)) & a20_mask; + pte_addr =3D (pte & ~0xfffu) + ((addr >> 10) & 0xffc); if (!ptw_translate(&pte_trans, pte_addr)) { return false; } --=20 2.39.2