From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 50731CAC597 for ; Thu, 18 Sep 2025 06:21:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uz815-0007Jh-8w; Thu, 18 Sep 2025 02:21:15 -0400 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 1uz813-0007Dr-Fi; Thu, 18 Sep 2025 02:21:13 -0400 Received: from [115.124.30.110] (helo=out30-110.freemail.mail.aliyun.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uz810-0007M8-FY; Thu, 18 Sep 2025 02:21:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1758176462; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=2LJHq3jM30JmCcRGqXgJjr29cgijIf4FuEVwfzZdKFE=; b=b6Wv6Ix4pGhSvQc1Hd45nIlA2T0V0gmtd9xH/BHYHXxJokYim1angDooM2SXfRHydXHP9JKvTIB1DlMl7s0Ut9Fjz0cEI+Wp/Gd4yvcWA1pvsqvJkFgz7DmEBujnk0GcLOxD6daQnG2wA87ta97jJIgT8qfwa+uenaWIS4YvIGs= Received: from localhost.localdomain(mailfrom:zhiwei_liu@linux.alibaba.com fp:SMTPD_---0WoEr5aR_1758176460 cluster:ay36) by smtp.aliyun-inc.com; Thu, 18 Sep 2025 14:21:01 +0800 From: LIU Zhiwei To: qemu-devel@nongnu.org Cc: qemu-riscv@nongnu.org, palmer@dabbelt.com, alistair.francis@wdc.com, dbarboza@ventanamicro.com, liwei1518@gmail.com, zhiwei_liu@linux.alibaba.com, Huang Tao , TANG Tiancheng Subject: [PATCH v2 3/6] target/riscv: Integrate SMMPT checks into MMU and TLB fill Date: Thu, 18 Sep 2025 14:19:08 +0800 Message-Id: <20250918061911.904-4-zhiwei_liu@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20250918061911.904-1-zhiwei_liu@linux.alibaba.com> References: <20250918061911.904-1-zhiwei_liu@linux.alibaba.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Host-Lookup-Failed: Reverse DNS lookup failed for 115.124.30.110 (deferred) Received-SPF: pass client-ip=115.124.30.110; envelope-from=zhiwei_liu@linux.alibaba.com; helo=out30-110.freemail.mail.aliyun.com X-Spam_score_int: -166 X-Spam_score: -16.7 X-Spam_bar: ---------------- X-Spam_report: (-16.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, ENV_AND_HDR_SPF_MATCH=-0.5, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, UNPARSEABLE_RELAY=0.001, USER_IN_DEF_DKIM_WL=-7.5, USER_IN_DEF_SPF_WL=-7.5 autolearn=no 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 With the core MPT lookup logic in place, this patch integrates the permission checks into QEMU's main MMU processing functions. A new helper, `get_physical_address_mpt`, is introduced to check the permissions for a given physical address against the MPT. This helper is then called at two critical points: 1. During page table walks (`get_physical_address`): The physical address of the Page Table Entry (PTE) itself is checked to ensure the supervisor has permission to read it. 2. After successful address translation (`riscv_cpu_tlb_fill`): The final guest-physical address is checked against the MPT before the access is allowed to proceed. This ensures that SMMPT protection is enforced for both the translation process and the final memory access, as required by the specification. Co-authored-by: Huang Tao Co-authored-by: TANG Tiancheng Signed-off-by: LIU Zhiwei Reviewed-by: Daniel Henrique Barboza --- target/riscv/cpu_helper.c | 81 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 77 insertions(+), 4 deletions(-) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 3479a62cc7..f8ca74ef61 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -1089,9 +1089,8 @@ void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv, bool virt_en) * @access_type: The type of MMU access * @mode: Indicates current privilege level. */ -static int get_physical_address_pmp(CPURISCVState *env, int *prot, hwaddr addr, - int size, MMUAccessType access_type, - int mode) +int get_physical_address_pmp(CPURISCVState *env, int *prot, hwaddr addr, + int size, MMUAccessType access_type, int mode) { pmp_priv_t pmp_priv; bool pmp_has_privs; @@ -1162,6 +1161,60 @@ static bool check_svukte_addr(CPURISCVState *env, vaddr addr) return !high_bit; } +/* + * get_physical_address_mpt - check mpt permission for this physical address + * + * Lookup the Memory Protection Table and check permission for this + * physical address. Returns 0 if the permission checking was successful + * + * @env: CPURISCVState + * @prot: The returned protection attributes + * @addr: The physical address to be checked permission + * @access_type: The type of MMU access + * @mode: Indicates current privilege level. + */ +static int get_physical_address_mpt(CPURISCVState *env, int *prot, hwaddr addr, + MMUAccessType access_type, int mode) +{ + mpt_access_t mpt_access; + bool mpt_has_access; + + /* + * If the extension is not supported or the mmpt.mode is Bare, + * there is no protection, return success. + */ + if (!riscv_cpu_cfg(env)->ext_smmpt || env->mptmode == 0) { + *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; + return TRANSLATE_SUCCESS; + } + + /* + * MPT is checked for all accesses to physical memory, unless the + * effective privilege mode is M. + * + * Data accesses in M-mode when the MPRV bit in mstatus is set and + * the MPP field in mstatus contains S or U are subject to MPT checks. + * + * In riscv_env_mmu_index, The MPRV and MPP bits are already checked and + * encoded to mmu_idx, So we do not need to check it here. + */ + if (mode == PRV_M) { + *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; + return TRANSLATE_SUCCESS; + } + + mpt_has_access = smmpt_check_access(env, addr, + &mpt_access, access_type); + if (!mpt_has_access) { + *prot = 0; + return TRANSLATE_MPT_FAIL; + } + + *prot = smmpt_access_to_page_prot(mpt_access); + + return TRANSLATE_SUCCESS; +} + /* * get_physical_address - get the physical address for this virtual address * @@ -1356,6 +1409,13 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, pte_addr = base + idx * ptesize; } + int mpt_prot; + int mpt_ret = get_physical_address_mpt(env, &mpt_prot, pte_addr, + MMU_DATA_LOAD, PRV_S); + if (mpt_ret != TRANSLATE_SUCCESS) { + return TRANSLATE_MPT_FAIL; + } + int pmp_prot; int pmp_ret = get_physical_address_pmp(env, &pmp_prot, pte_addr, sxlen_bytes, @@ -1766,7 +1826,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, CPURISCVState *env = &cpu->env; vaddr im_address; hwaddr pa = 0; - int prot, prot2, prot_pmp; + int prot, prot2, prot_pmp, mpt_prot; bool pmp_violation = false; bool first_stage_error = true; bool two_stage_lookup = mmuidx_2stage(mmu_idx); @@ -1820,6 +1880,13 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, prot &= prot2; if (ret == TRANSLATE_SUCCESS) { + ret = get_physical_address_mpt(env, &mpt_prot, pa, + access_type, mode); + qemu_log_mask(CPU_LOG_MMU, + "%s MPT address=" HWADDR_FMT_plx " ret %d prot" + " %d\n", + __func__, pa, ret, mpt_prot); + prot &= mpt_prot; ret = get_physical_address_pmp(env, &prot_pmp, pa, size, access_type, mode); tlb_size = pmp_get_tlb_size(env, pa); @@ -1855,6 +1922,12 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, __func__, address, ret, pa, prot); if (ret == TRANSLATE_SUCCESS) { + ret = get_physical_address_mpt(env, &mpt_prot, pa, + access_type, mode); + qemu_log_mask(CPU_LOG_MMU, + "%s MPT address=" HWADDR_FMT_plx " ret %d prot %d\n", + __func__, pa, ret, mpt_prot); + prot &= mpt_prot; ret = get_physical_address_pmp(env, &prot_pmp, pa, size, access_type, mode); tlb_size = pmp_get_tlb_size(env, pa); -- 2.25.1