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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 AE9FDC43458 for ; Tue, 14 Jul 2026 09:49:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=wyTWW8HBVSp85RJKDsevItXkUCxyxu6rEHPnqkvSln8=; b=1CNGoJ7VxuJhmKKXQpeHIkxd8N hLXmrB9rsMPCXU3OVwzJVt6BAtP2H/Tu5SFQUOMZ37azarDT6zbkxEMIyQPie0HoCFCes2VsFIiCH J/GwIQeiGVUYCHF6Xcahy9/k9E8pxEOH45Ud2W6ioZeDv0XH6Inc//G3UDAoj7SNfKeRZTSn+uSEz ArFLQPd5sVzepoCq3EC4DXEmLjvJXijCcqvnH1jVwy7lTUUK41w9hB/77mM5WulkRZt7FUTcymH9R etVy9qtSE63TLYNogejw4f66mWJwcjos81aRqPwRshgoEoav+sPoThkX5ppKzNX4w3Lx/lwfgR/Rt Yihss55g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wjZG9-0000000BP9s-3UO0; Tue, 14 Jul 2026 09:17:02 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wjZFy-0000000BP16-0Zfv for linux-arm-kernel@lists.infradead.org; Tue, 14 Jul 2026 09:16:50 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 12D7443C9F; Tue, 14 Jul 2026 09:16:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED10A1F00A3F; Tue, 14 Jul 2026 09:16:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784020610; bh=wyTWW8HBVSp85RJKDsevItXkUCxyxu6rEHPnqkvSln8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mnuVfWpPj0qR/VUUBkgDsMyUY+PL1TYyhkweSS60wPZ5PPZjDaA8tPFYnnXdVW+0A 8Uglb69ZymW7B6MBfx5cP69e85GxHA0narX7/e1kPHvVbzDSZkVzvhE2O7bgzP0m+x wkHnxMKACrFT/8Im134RfT13Bj1I5/fKo8XEi66LxDmzUb6u42iPwkV0CvErTHr5Ng +vuY2OryEIu6GqDVrJ6HUCaJh2ZnRfLJLFpJdnzFjP3iJwpiWWTSl0tAskGzvIMMRX p5zN0Jz8iUEPwiSUbZ/DY7BRlMraRzgnWPiFL3LnBUgwBksZGUywK2pnzuS0klyHtA WRXX1UBpK/9nQ== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wjZFw-00000004ny1-10b7; Tue, 14 Jul 2026 09:16:48 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: Steffen Eiden , Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu Subject: [PATCH v2 06/28] KVM: arm64: Classify CPTR_EL2 as a SR_LOC_SPECIAL register Date: Tue, 14 Jul 2026 10:16:19 +0100 Message-ID: <20260714091641.1970822-7-maz@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260714091641.1970822-1-maz@kernel.org> References: <20260714091641.1970822-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, seiden@linux.ibm.com, joey.gouly@arm.com, suzuki.poulose@arm.com, oupton@kernel.org, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org It may not be obvious unless you look at it closely, but CPTR_EL2 is treated very differently from other registers. It is one the registers that, despite looking very similar between EL1 and EL2 when E2H==1, have RES0 bits that get in the way. Make it clear that CPTR_EL2 is odd by classifying it as SR_LOC_SPECIAL, just like CNTHCTL_EL2 (and for the same reasons). This makes it possible to use vcpu_read_sys_reg() with it, and will be necessary once we support FEAT_NV2P1. Reviewed-by: Joey Gouly Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_emulate.h | 2 +- arch/arm64/kvm/sys_regs.c | 20 ++++++++++++++++++-- 2 files changed, 19 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 5bf3d7e1d92c7..9831166695186 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -617,7 +617,7 @@ static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu) */ static inline u64 vcpu_sanitised_cptr_el2(const struct kvm_vcpu *vcpu) { - u64 cptr = __vcpu_sys_reg(vcpu, CPTR_EL2); + u64 cptr = vcpu_read_sys_reg(vcpu, CPTR_EL2); if (!vcpu_el2_e2h_is_set(vcpu)) cptr = translate_cptr_el2_to_cpacr_el1(cptr); diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 5d5c579d45790..6b47d936efb32 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -183,8 +183,6 @@ static void locate_register(const struct kvm_vcpu *vcpu, enum vcpu_sysreg reg, switch (reg) { MAPPED_EL2_SYSREG(SCTLR_EL2, SCTLR_EL1, translate_sctlr_el2_to_sctlr_el1 ); - MAPPED_EL2_SYSREG(CPTR_EL2, CPACR_EL1, - translate_cptr_el2_to_cpacr_el1 ); MAPPED_EL2_SYSREG(TTBR0_EL2, TTBR0_EL1, translate_ttbr0_el2_to_ttbr0_el1 ); MAPPED_EL2_SYSREG(TTBR1_EL2, TTBR1_EL1, NULL ); @@ -210,6 +208,19 @@ static void locate_register(const struct kvm_vcpu *vcpu, enum vcpu_sysreg reg, loc->loc = ((is_hyp_ctxt(vcpu) && vcpu_el2_e2h_is_set(vcpu)) ? SR_LOC_SPECIAL : SR_LOC_MEMORY); break; + case CPTR_EL2: + /* + * CPTR_EL2 is just as special, and needs a certain amount + * of handholding. It always lives in memory, due to being + * heavily trapped thanks to CPACR_EL1.TCPAC being RES0. + * FEAT_NV2p1 fixes this. + */ + locate_mapped_el2_register(vcpu, CPTR_EL2, CPACR_EL1, + translate_cptr_el2_to_cpacr_el1, + loc); + if (is_hyp_ctxt(vcpu) && vcpu_el2_e2h_is_set(vcpu)) + loc->loc = SR_LOC_SPECIAL; + break; default: loc->loc = locate_direct_register(vcpu, reg); } @@ -314,6 +325,8 @@ u64 vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, enum vcpu_sysreg reg) val &= CNTKCTL_VALID_BITS; val |= __vcpu_sys_reg(vcpu, reg) & ~CNTKCTL_VALID_BITS; return val; + case CPTR_EL2: + return __vcpu_sys_reg(vcpu, reg); default: WARN_ON_ONCE(1); } @@ -359,6 +372,9 @@ void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, enum vcpu_sysreg reg) */ write_sysreg_el1(val, SYS_CNTKCTL); break; + case CPTR_EL2: + write_sysreg_el1(val, SYS_CPACR); + break; default: WARN_ON_ONCE(1); } -- 2.47.3