From patchwork Fri Apr 28 14:36:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Weiwei Li X-Patchwork-Id: 13226488 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 59656C77B60 for ; Fri, 28 Apr 2023 14:37:30 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1psPDP-00029D-7o; Fri, 28 Apr 2023 10:36:51 -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 1psPDJ-00023x-Kv; Fri, 28 Apr 2023 10:36:45 -0400 Received: from [159.226.251.80] (helo=cstnet.cn) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1psPDF-0008AR-C7; Fri, 28 Apr 2023 10:36:45 -0400 Received: from localhost.localdomain (unknown [61.165.33.195]) by APP-01 (Coremail) with SMTP id qwCowACHj3vq2UtkrB5ZDA--.57839S3; Fri, 28 Apr 2023 22:36:28 +0800 (CST) From: Weiwei Li To: qemu-riscv@nongnu.org, qemu-devel@nongnu.org Cc: palmer@dabbelt.com, alistair.francis@wdc.com, bin.meng@windriver.com, dbarboza@ventanamicro.com, zhiwei_liu@linux.alibaba.com, richard.henderson@linaro.org, wangjunqiang@iscas.ac.cn, lazyparser@gmail.com, Weiwei Li Subject: [PATCH v5 01/13] target/riscv: Update pmp_get_tlb_size() Date: Fri, 28 Apr 2023 22:36:09 +0800 Message-Id: <20230428143621.142390-2-liweiwei@iscas.ac.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230428143621.142390-1-liweiwei@iscas.ac.cn> References: <20230428143621.142390-1-liweiwei@iscas.ac.cn> MIME-Version: 1.0 X-CM-TRANSID: qwCowACHj3vq2UtkrB5ZDA--.57839S3 X-Coremail-Antispam: 1UD129KBjvJXoWxtrW7Aw1DXr15XF17JF15XFb_yoW7AFyxpr WxCrW7GrZ7K39xJ3W3JF4DXF15Cw4fKr45Aa97WFWvka15G3yrAr1qkr4a9ry8GayDurWY 9FWqyFn8CF4UXaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPl14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l84 ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2IY04 v7MxkIecxEwVAFwVW5XwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC2 0s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI 0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv2 0xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2js IE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZF pf9x0JUwqXQUUUUU= X-Originating-IP: [61.165.33.195] X-CM-SenderInfo: 5olzvxxzhlqxpvfd2hldfou0/ X-Host-Lookup-Failed: Reverse DNS lookup failed for 159.226.251.80 (deferred) Received-SPF: pass client-ip=159.226.251.80; envelope-from=liweiwei@iscas.ac.cn; helo=cstnet.cn X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_MSPIKE_H2=-0.001, RDNS_NONE=0.793, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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 PMP entries before the matched PMP entry (including the matched PMP entry) may only cover partial of the TLB page, which may make different regions in that page allow different RWX privs. Such as for PMP0 (0x80000008~0x8000000F, R) and PMP1 (0x80000000~0x80000FFF, RWX), write access to 0x80000000 will match PMP1. However we cannot cache the translation result in the TLB since this will make the write access to 0x80000008 bypass the check of PMP0. So we should check all of them instead of the matched PMP entry in pmp_get_tlb_size() and set the tlb_size to 1 in this case. Set tlb_size to TARGET_PAGE_SIZE if PMP is not support or there is no PMP rules. Signed-off-by: Weiwei Li Signed-off-by: Junqiang Wang Reviewed-by: LIU Zhiwei Reviewed-by: Alistair Francis --- target/riscv/cpu_helper.c | 7 ++--- target/riscv/pmp.c | 64 ++++++++++++++++++++++++++++++--------- target/riscv/pmp.h | 3 +- 3 files changed, 52 insertions(+), 22 deletions(-) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 433ea529b0..075fc0538a 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -703,11 +703,8 @@ static int get_physical_address_pmp(CPURISCVState *env, int *prot, } *prot = pmp_priv_to_page_prot(pmp_priv); - if ((tlb_size != NULL) && pmp_index != MAX_RISCV_PMPS) { - target_ulong tlb_sa = addr & ~(TARGET_PAGE_SIZE - 1); - target_ulong tlb_ea = tlb_sa + TARGET_PAGE_SIZE - 1; - - *tlb_size = pmp_get_tlb_size(env, pmp_index, tlb_sa, tlb_ea); + if (tlb_size != NULL) { + *tlb_size = pmp_get_tlb_size(env, addr); } return TRANSLATE_SUCCESS; diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c index 1f5aca42e8..ad20a319c1 100644 --- a/target/riscv/pmp.c +++ b/target/riscv/pmp.c @@ -601,28 +601,62 @@ target_ulong mseccfg_csr_read(CPURISCVState *env) } /* - * Calculate the TLB size if the start address or the end address of - * PMP entry is presented in the TLB page. + * Calculate the TLB size. If the PMP rules may make different regions in + * the TLB page of 'addr' allow different RWX privs, set the size to 1 + * (to make the translation result uncached in the TLB and only be used for + * a single translation). Set the size to TARGET_PAGE_SIZE otherwise. */ -target_ulong pmp_get_tlb_size(CPURISCVState *env, int pmp_index, - target_ulong tlb_sa, target_ulong tlb_ea) +target_ulong pmp_get_tlb_size(CPURISCVState *env, target_ulong addr) { - target_ulong pmp_sa = env->pmp_state.addr[pmp_index].sa; - target_ulong pmp_ea = env->pmp_state.addr[pmp_index].ea; + target_ulong pmp_sa; + target_ulong pmp_ea; + target_ulong tlb_sa = addr & ~(TARGET_PAGE_SIZE - 1); + target_ulong tlb_ea = tlb_sa + TARGET_PAGE_SIZE - 1; + int i; - if (pmp_sa <= tlb_sa && pmp_ea >= tlb_ea) { + /* + * If PMP is not supported or there is no PMP rule, which means the allowed + * RWX privs of the page will not affected by PMP or PMP will provide the + * same option (disallow accesses or allow default RWX privs) for all + * addresses, set the size to TARGET_PAGE_SIZE. + */ + if (!riscv_cpu_cfg(env)->pmp || !pmp_get_num_rules(env)) { return TARGET_PAGE_SIZE; - } else { + } + + for (i = 0; i < MAX_RISCV_PMPS; i++) { + if (pmp_get_a_field(env->pmp_state.pmp[i].cfg_reg) == PMP_AMATCH_OFF) { + continue; + } + + pmp_sa = env->pmp_state.addr[i].sa; + pmp_ea = env->pmp_state.addr[i].ea; + /* - * At this point we have a tlb_size that is the smallest possible size - * That fits within a TARGET_PAGE_SIZE and the PMP region. - * - * If the size is less then TARGET_PAGE_SIZE we drop the size to 1. - * This means the result isn't cached in the TLB and is only used for - * a single translation. + * Only the first PMP entry that covers (whole or partial of) the TLB + * page really matters: + * If it can cover the whole page, set the size to TARGET_PAGE_SIZE. + * The following PMP entries have lower priority and will not affect + * the allowed RWX privs of the page. + * If it only cover partial of the TLB page, set the size to 1 since + * the allowed RWX privs for the covered region may be different from + * other region of the page. */ - return 1; + if (pmp_sa <= tlb_sa && pmp_ea >= tlb_ea) { + return TARGET_PAGE_SIZE; + } else if ((pmp_sa >= tlb_sa && pmp_sa <= tlb_ea) || + (pmp_ea >= tlb_sa && pmp_ea <= tlb_ea)) { + return 1; + } } + + /* + * If no PMP entry covers any region of the TLB page, similar to the above + * case that there is no PMP rule, PMP will provide the same option + * (disallow accesses or allow default RWX privs) for the whole page, + * set the size to TARGET_PAGE_SIZE. + */ + return TARGET_PAGE_SIZE; } /* diff --git a/target/riscv/pmp.h b/target/riscv/pmp.h index b296ea1fc6..0a7e24750b 100644 --- a/target/riscv/pmp.h +++ b/target/riscv/pmp.h @@ -76,8 +76,7 @@ int pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, target_ulong size, pmp_priv_t privs, pmp_priv_t *allowed_privs, target_ulong mode); -target_ulong pmp_get_tlb_size(CPURISCVState *env, int pmp_index, - target_ulong tlb_sa, target_ulong tlb_ea); +target_ulong pmp_get_tlb_size(CPURISCVState *env, target_ulong addr); void pmp_update_rule_addr(CPURISCVState *env, uint32_t pmp_index); void pmp_update_rule_nums(CPURISCVState *env); uint32_t pmp_get_num_rules(CPURISCVState *env);