From patchwork Sat Nov 9 10:14:26 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 13869387 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 ADF42D5E362 for ; Sat, 9 Nov 2024 10:24:47 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1t9icC-00071g-Qd; Sat, 09 Nov 2024 05:22:48 -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 1t9iXR-0007nF-Fk; Sat, 09 Nov 2024 05:17:55 -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 1t9iXP-00089O-QO; Sat, 09 Nov 2024 05:17:53 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 3088AA1408; Sat, 9 Nov 2024 13:13:51 +0300 (MSK) Received: from think4mjt.tls.msk.ru (mjtthink.wg.tls.msk.ru [192.168.177.146]) by tsrv.corpit.ru (Postfix) with ESMTP id CFD86167EF3; Sat, 9 Nov 2024 13:14:45 +0300 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Evgenii Prokopiev , Daniel Henrique Barboza , Alistair Francis , Michael Tokarev Subject: [Stable-8.2.8 35/49] target/riscv/csr.c: Fix an access to VXSAT Date: Sat, 9 Nov 2024 13:14:26 +0300 Message-Id: <20241109101443.312701-35-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.5 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, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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 From: Evgenii Prokopiev The register VXSAT should be RW only to the first bit. The remaining bits should be 0. The RISC-V Instruction Set Manual Volume I: Unprivileged Architecture The vxsat CSR has a single read-write least-significant bit (vxsat[0]) that indicates if a fixed-point instruction has had to saturate an output value to fit into a destination format. Bits vxsat[XLEN-1:1] should be written as zeros. Signed-off-by: Evgenii Prokopiev Reviewed-by: Daniel Henrique Barboza Reviewed-by: Alistair Francis Message-ID: <20241002084436.89347-1-evgenii.prokopiev@syntacore.com> Signed-off-by: Alistair Francis (cherry picked from commit 5a60026cad4e9dba929cab4f63229e4b9110cf0a) Signed-off-by: Michael Tokarev diff --git a/target/riscv/csr.c b/target/riscv/csr.c index c50a33397c..3d9ea0c316 100644 --- a/target/riscv/csr.c +++ b/target/riscv/csr.c @@ -704,7 +704,7 @@ static RISCVException write_vxrm(CPURISCVState *env, int csrno, static RISCVException read_vxsat(CPURISCVState *env, int csrno, target_ulong *val) { - *val = env->vxsat; + *val = env->vxsat & BIT(0); return RISCV_EXCP_NONE; } @@ -714,7 +714,7 @@ static RISCVException write_vxsat(CPURISCVState *env, int csrno, #if !defined(CONFIG_USER_ONLY) env->mstatus |= MSTATUS_VS; #endif - env->vxsat = val; + env->vxsat = val & BIT(0); return RISCV_EXCP_NONE; }