From patchwork Wed Aug 21 23:55:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Deepak Gupta X-Patchwork-Id: 1975152 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=Qnw2y7pk; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.a=rsa-sha256 header.s=20230601 header.b=cyu/rJa1; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:3::133; helo=bombadil.infradead.org; envelope-from=opensbi-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=patchwork.ozlabs.org) Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Wq3Bb3hYyz1yf6 for ; Thu, 22 Aug 2024 09:56:06 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=nE67adIXMtv7aD/ygsPbU5HRyphQgPOTN0cR/pPaQN8=; b=Qnw2y7pkkuinJb cmR+FI/qXAMiGLzc3FU1DuPxuCoHDnk1VF2LQqRWVXYg2n8nhktS39XBYRtssZDQi1bfezhfX85rX N8+25h6nccMjqPy36TwCOWzDvKVKd4Xz+5aqXWz0aqo5Nouoojp0A/s9UO9sEcpU7toNv/uhUokNM lieS3pnTGHXBCCApPPKIeb+saKb+NeATdwGjHx16ToM9fMJGgEQf9XJnCKJ58yw985VHzMPhWsJYL mqeydmNL1RmglS+tlEReUGuVvR+084Ihr/h1P55DmpzutK9dxxMeDivRVC/iT9wh0R4WB45M1Z42G 3fJJX5awVm2DEdCA7O4g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgvBE-0000000AiBu-45fJ; Wed, 21 Aug 2024 23:55:56 +0000 Received: from mail-pl1-x62c.google.com ([2607:f8b0:4864:20::62c]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgvBA-0000000AiAY-3gyg for opensbi@lists.infradead.org; Wed, 21 Aug 2024 23:55:54 +0000 Received: by mail-pl1-x62c.google.com with SMTP id d9443c01a7336-2020b730049so2038995ad.3 for ; Wed, 21 Aug 2024 16:55:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1724284552; x=1724889352; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=8CO802vhzJx96HkKfaI0kRI4b3sWztye8jLUO3nHSpw=; b=cyu/rJa1bxVtTdCdFehT6LI5P0ParqqVnCh0Ll80dtRrY6lG8UdHFhZczkwaKuQNS+ 6lwV/Xe1Xg6Ab5tUx1Uqrr0rs/6hitVMDtiwjtAbYxhHRKk9WCbQHBA8l/9QT5zUEfVy aHU4w/whcva9AEYL3/O3e/OqLrml3zoibXieI+M8ClFCXoxFb981D1BexCx5lHRAkgvm 9PA/AAZhL/jbUnQ4JjkMU+XPy1NmysPfbyZFOtsfaHxY9gS1+eyOTW1c9RqqYZzo7rIH GqbLgtqVwhXgcpv2i33QeXjsnbCLL0M8lfI6BKLgoO/XathmSdIn42Tp/0xbRoojsJzt TP7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724284552; x=1724889352; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8CO802vhzJx96HkKfaI0kRI4b3sWztye8jLUO3nHSpw=; b=K80GTJcllnHhP4H707l2Y93Es2pWBh4HTPyf8rPIMPDaRHw7Qcx084jOXUUp6mNZvV xwY8SZA6b73hWceMSvbb1rsai8P50ddFCHD7dr4s9FYcRJUNbwa6Jbzd/B9Hair464/I YuF0uK6d+Qik312e6QrBRP76rOWE0tDnfaWM3vSxk5agTuf+TRSfcrGZNPqy7UeHbzI0 RGB+/KdvEEKX5wOJQKSNJfkURedrhonzBFmhrV8X+cI63nsygUeMql8h+hdHVdvW5c3g 4lC62SN9jF071smhJsdt8UC6VpPi1g679ZBoXj3lnE9TrZDIodxPzIx0dGGKyvc7Hkus TUWA== X-Gm-Message-State: AOJu0YygHGiEJcM0rRxsq4iCkwXEP9WZ4dmlV9tlm6y+l2zxihZ/AbVI KJ+p7ND2pt4Owkd499YT1JbI6aWtU3J0rhTwnx0D+DK+1T4DwX0ZnoPhxpHTD6TkMfHmgcwt+vU 7 X-Google-Smtp-Source: AGHT+IFsEEuvdr1qO2YVT20EX+p6YOd7ouL6m3qwDLDMmQnJ9RMncW004ZvKIMJcvKwxXls+m+Xr1Q== X-Received: by 2002:a17:902:e891:b0:1fd:672f:2b34 with SMTP id d9443c01a7336-2038824f0efmr1999225ad.33.1724284551599; Wed, 21 Aug 2024 16:55:51 -0700 (PDT) Received: from debug.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2038556661csm1515495ad.24.2024.08.21.16.55.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Aug 2024 16:55:51 -0700 (PDT) From: Deepak Gupta To: opensbi@lists.infradead.org Cc: atishp@rivosinc.com, apatel@ventanamicro.com, Deepak Gupta Subject: [PATCH 2/3] lib: sbi: Zicfilp/Zicfiss detection and elp cfi state reflect back in status Date: Wed, 21 Aug 2024 16:55:45 -0700 Message-ID: <20240821235546.3876172-3-debug@rivosinc.com> X-Mailer: git-send-email 2.45.0 In-Reply-To: <20240821235546.3876172-1-debug@rivosinc.com> References: <20240821235546.3876172-1-debug@rivosinc.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240821_165552_941805_9190A739 X-CRM114-Status: GOOD ( 13.25 ) X-Spam-Score: -1.9 (-) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: This patch adds support for zicfilp / zicfiss detection in sbi_hart.c If zicfilp and zicfiss are detected, this patch turns on menvcfg.LPE and menvcfg.SSE Zicfilp records status of hart's ELP state in *status csr. Missing landing pad sets MPELP in mstatus. When SBI is redirecting back to S/VS/HS, SPELP is set in sstatus/vsstatus. Content analysis details: (-1.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [2607:f8b0:4864:20:0:0:0:62c listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] -0.0 T_SCC_BODY_TEXT_LINE No description available. X-BeenThere: opensbi@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "opensbi" Errors-To: opensbi-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org This patch adds support for zicfilp / zicfiss detection in sbi_hart.c If zicfilp and zicfiss are detected, this patch turns on menvcfg.LPE and menvcfg.SSE Zicfilp records status of hart's ELP state in *status csr. Missing landing pad sets MPELP in mstatus. When SBI is redirecting back to S/VS/HS, SPELP is set in sstatus/vsstatus. Signed-off-by: Deepak Gupta --- lib/sbi/sbi_hart.c | 28 ++++++++++++++++++++++++++++ lib/sbi/sbi_trap.c | 16 ++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c index c366701..67a2e42 100644 --- a/lib/sbi/sbi_hart.c +++ b/lib/sbi/sbi_hart.c @@ -148,6 +148,16 @@ static void mstatus_init(struct sbi_scratch *scratch) if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SVADE)) menvcfg_val &= ~ENVCFG_ADUE; + /* + * By default allow shadow stack opreations in S/HS mode + * don't enable landing pad because supervisor may keep faulting + * due to missing landing pad. Open up a SBI interface to enable + * landing pad + */ + if (sbi_hart_has_extension(scratch, SBI_HART_EXT_ZICFISS)) { + menvcfg_val |= ENVCFG_SSE; + } + csr_write(CSR_MENVCFG, menvcfg_val); #if __riscv_xlen == 32 csr_write(CSR_MENVCFGH, menvcfg_val >> 32); @@ -680,6 +690,8 @@ const struct sbi_hart_ext_data sbi_hart_ext[] = { __SBI_HART_EXT_DATA(ssccfg, SBI_HART_EXT_SSCCFG), __SBI_HART_EXT_DATA(svade, SBI_HART_EXT_SVADE), __SBI_HART_EXT_DATA(svadu, SBI_HART_EXT_SVADU), + __SBI_HART_EXT_DATA(zicfilp, SBI_HART_EXT_ZICFILP), + __SBI_HART_EXT_DATA(zicfiss, SBI_HART_EXT_ZICFISS), }; _Static_assert(SBI_HART_EXT_MAX == array_size(sbi_hart_ext), @@ -776,6 +788,7 @@ static int hart_detect_features(struct sbi_scratch *scratch) unsigned long val, oldval; bool has_zicntr = false; int rc; + bool ssp_exist, elp_exist; /* If hart features already detected then do nothing */ if (hfeatures->detected) @@ -933,6 +946,21 @@ __pmp_skip: /* Save trap based detection of Zicntr */ has_zicntr = sbi_hart_has_extension(scratch, SBI_HART_EXT_ZICNTR); + if (hfeatures->priv_version >= SBI_HART_PRIV_VER_1_12) { + val = csr_read_allowed(CSR_SSP, (unsigned long)&trap); + ssp_exist = trap.cause == 0; + if (ssp_exist) + __sbi_hart_update_extension(hfeatures, + SBI_HART_EXT_ZICFISS, true); + + csr_set(CSR_MSTATUS, MSTATUS_MPELP); + val = csr_read_clear(CSR_MSTATUS, MSTATUS_MPELP); + elp_exist = val & MSTATUS_MPELP; + if (elp_exist) + __sbi_hart_update_extension(hfeatures, + SBI_HART_EXT_ZICFILP, true); + } + /* Let platform populate extensions */ rc = sbi_platform_extensions_init(sbi_platform_thishart_ptr(), hfeatures); diff --git a/lib/sbi/sbi_trap.c b/lib/sbi/sbi_trap.c index b4f3a17..2273b3a 100644 --- a/lib/sbi/sbi_trap.c +++ b/lib/sbi/sbi_trap.c @@ -103,6 +103,7 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, const struct sbi_trap_info *trap) { ulong hstatus, vsstatus, prev_mode; + bool elp = false; #if __riscv_xlen == 32 bool prev_virt = (regs->mstatusH & MSTATUSH_MPV) ? true : false; #else @@ -116,6 +117,13 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, if (prev_mode != PRV_S && prev_mode != PRV_U) return SBI_ENOTSUPP; + /* If extension has support for CFI, clear MPELP because redirecting to VS or (H)S */ + if (sbi_hart_has_extension(sbi_scratch_thishart_ptr(), SBI_HART_EXT_ZICFILP)) { + elp = (regs->mstatus & MSTATUS_MPELP)? true: false; + /* Since redirecting, clear mpelp unconditionally */ + regs->mstatus &= ~MSTATUS_MPELP; + } + /* If exceptions came from VS/VU-mode, redirect to VS-mode if * delegated in hedeleg */ @@ -169,6 +177,10 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, /* Get VS-mode SSTATUS CSR */ vsstatus = csr_read(CSR_VSSTATUS); + /*if elp was set, set it back in vsstatus */ + if (elp) + vsstatus |= MSTATUS_SPELP; + /* Set SPP for VS-mode */ vsstatus &= ~SSTATUS_SPP; if (prev_mode == PRV_S) @@ -209,6 +221,10 @@ int sbi_trap_redirect(struct sbi_trap_regs *regs, /* Clear SIE for S-mode */ regs->mstatus &= ~MSTATUS_SIE; + + /* if elp was set, set it back in mstatus */ + if (elp) + regs->mstatus |= MSTATUS_SPELP; } return 0;