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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27200C433EF for ; Fri, 29 Oct 2021 00:32:53 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id A978D610F8 for ; Fri, 29 Oct 2021 00:32:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A978D610F8 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 45C624B15C; Thu, 28 Oct 2021 20:32:52 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Evc9opFL-N03; Thu, 28 Oct 2021 20:32:50 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0B6754B19A; Thu, 28 Oct 2021 20:32:49 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4356E4B172 for ; Thu, 28 Oct 2021 20:32:46 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Z0fb84wYTcZQ for ; Thu, 28 Oct 2021 20:32:44 -0400 (EDT) Received: from mail-ot1-f73.google.com (mail-ot1-f73.google.com [209.85.210.73]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id D6D3F4B160 for ; Thu, 28 Oct 2021 20:32:43 -0400 (EDT) Received: by mail-ot1-f73.google.com with SMTP id r3-20020a056830236300b0054d43b72ba5so4348916oth.17 for ; Thu, 28 Oct 2021 17:32:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=8jHkcukOGs60Vh8sqIk5PEDCEkQaDcCSTeMEW1ZoThU=; b=JdhR5KgizbNUUTAjmlYRxJx0EtRpzClBjN8sNGCA4JJO4HHHb6OXPbkGWVWsexwurl kRU/OrYOvFTWusWVmdojV2LmmS3eksr37DnFEYydJYDaWiHjFtnAErqEYg97xPlTHxHn nLUvfSd9uIXXDeEqhI/d07olbwebG44JjMzSvnmAiFv9ny7vqeJmJcMZCzv9Txyee4A1 AH50A4MUa8rJlxoiWXiA/FNFIrwGua22jIX3diDsCegQ2R353dFwc0iVF1Ubi2YZ4UDY m1tQpzc7VBbKbCWLZcVd52Qs91rPh+JGCvqvxhTGc6bQlM+BZoafUHzt0/wQE/NVWNBr 1N3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=8jHkcukOGs60Vh8sqIk5PEDCEkQaDcCSTeMEW1ZoThU=; b=temF4CuwD1wUIaPCRbU2PBc5gGdX8TVt3xEFKbHAU0lRV+vRc/4AdCB3JGYlFBaePw QRlLeh6zdWuPzVVu7Gp4xvWL1HtSdcfGLPsMkWdgTTnkLwdxznEMVdNamMY39EwXMGsQ +noabz9MBX+dTK09jTojCmQZUooBM/aywTWJo2VlZ4NIzCLZs3Y8Ef4/DOH1bFlK3kRL TssPccLNM0U/i7WI4xA2aGpnhwmNV7uRO7Bj9Ek9dISaypdcap0ACT32Fu3wfKUejrb8 BznZ7QVDSFZFDSIKSJsETbhNSmmV6qBEihRbuqlWJOKTJsTdDd5cYQ3JlRq56DZCtCP6 aTbQ== X-Gm-Message-State: AOAM531m73bQsSbVBKPYrui8W4pdVb/4GOee7eN6jhq0mqvklqz79xaV z4/GYiU+JiS9j/CiORNf+Ee1jKBEIEUDE7RBEcrnBrCByBOGPqk2Ta8seQ+GiK5ls/dCSiQ1ujD w+ivYZeW/IX8wzarj14HSc20OcQSrQ0rb9O7Yxc0s0EDecUhSXfFgHlY4Z4UUTazRdrFhBw== X-Google-Smtp-Source: ABdhPJyaxDFxxmg122WEeWbg/RrVAHJJLIJnz/MlGJ2fjJIs/pCIhzGPDOjoXFCCGLJwb76Yre8ULKN1ULY= X-Received: from oupton.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:404]) (user=oupton job=sendgmr) by 2002:aca:3e86:: with SMTP id l128mr11380539oia.120.1635467563254; Thu, 28 Oct 2021 17:32:43 -0700 (PDT) Date: Fri, 29 Oct 2021 00:32:01 +0000 In-Reply-To: <20211029003202.158161-1-oupton@google.com> Message-Id: <20211029003202.158161-3-oupton@google.com> Mime-Version: 1.0 References: <20211029003202.158161-1-oupton@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [PATCH 2/3] KVM: arm64: Allow the guest to change the OS Lock status From: Oliver Upton To: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org, Marc Zyngier , Peter Shier , linux-arm-kernel@lists.infradead.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu KVM diverges from the architecture in the way it handles the OSLAR_EL1 register. While the architecture requires that the register be WO and that the OSLK bit is 1 out of reset, KVM implements the register as RAZ/WI. Align KVM with the architecture by permitting writes to OSLAR_EL1. Since the register is WO, stash the OS Lock status bit in OSLSR_EL1 and context switch the status between host/guest. Additionally, change the reset value of the OSLK bit to 1. Suggested-by: Marc Zyngier Signed-off-by: Oliver Upton --- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 5 +++++ arch/arm64/kvm/sys_regs.c | 22 +++++++++++++++++++--- 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h index de7e14c862e6..a65dab34f85b 100644 --- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -65,6 +65,8 @@ static inline void __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) ctxt_sys_reg(ctxt, SP_EL1) = read_sysreg(sp_el1); ctxt_sys_reg(ctxt, ELR_EL1) = read_sysreg_el1(SYS_ELR); ctxt_sys_reg(ctxt, SPSR_EL1) = read_sysreg_el1(SYS_SPSR); + + ctxt_sys_reg(ctxt, OSLSR_EL1) = read_sysreg(oslsr_el1); } static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt) @@ -149,6 +151,9 @@ static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) write_sysreg(ctxt_sys_reg(ctxt, SP_EL1), sp_el1); write_sysreg_el1(ctxt_sys_reg(ctxt, ELR_EL1), SYS_ELR); write_sysreg_el1(ctxt_sys_reg(ctxt, SPSR_EL1), SYS_SPSR); + + /* restore OSLSR_EL1 by writing the OSLK bit to OSLAR_EL1 */ + write_sysreg((ctxt_sys_reg(ctxt, OSLSR_EL1) >> 1) & 1, oslar_el1); } static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 0eb03e7508fe..0840ae081290 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -298,6 +298,22 @@ static bool trap_oslsr_el1(struct kvm_vcpu *vcpu, return true; } +static bool trap_oslar_el1(struct kvm_vcpu *vcpu, + struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + u64 oslsr; + + if (!p->is_write) + return read_zero(vcpu, p); + + /* preserve all but the OSLK bit */ + oslsr = vcpu_read_sys_reg(vcpu, OSLSR_EL1) & ~0x2ull; + vcpu_write_sys_reg(vcpu, OSLSR_EL1, oslsr | ((p->regval & 1) << 1)); + return true; +} + + static bool trap_dbgauthstatus_el1(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) @@ -1439,8 +1455,8 @@ static const struct sys_reg_desc sys_reg_descs[] = { DBG_BCR_BVR_WCR_WVR_EL1(15), { SYS_DESC(SYS_MDRAR_EL1), trap_raz_wi }, - { SYS_DESC(SYS_OSLAR_EL1), trap_raz_wi }, - { SYS_DESC(SYS_OSLSR_EL1), trap_oslsr_el1, reset_val, OSLSR_EL1, 0x00000008 }, + { SYS_DESC(SYS_OSLAR_EL1), trap_oslar_el1 }, + { SYS_DESC(SYS_OSLSR_EL1), trap_oslsr_el1, reset_val, OSLSR_EL1, 0x0000000A }, { SYS_DESC(SYS_OSDLR_EL1), trap_raz_wi }, { SYS_DESC(SYS_DBGPRCR_EL1), trap_raz_wi }, { SYS_DESC(SYS_DBGCLAIMSET_EL1), trap_raz_wi }, @@ -1912,7 +1928,7 @@ static const struct sys_reg_desc cp14_regs[] = { DBGBXVR(0), /* DBGOSLAR */ - { Op1( 0), CRn( 1), CRm( 0), Op2( 4), trap_raz_wi }, + { Op1( 0), CRn( 1), CRm( 0), Op2( 4), trap_oslar_el1 }, DBGBXVR(1), /* DBGOSLSR */ { Op1( 0), CRn( 1), CRm( 1), Op2( 4), trap_oslsr_el1, NULL, OSLSR_EL1 }, -- 2.33.0.1079.g6e70778dc9-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm