From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0079D606A31A for ; Thu, 29 Oct 2026 11:36:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=LhjLtXCf; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=KjZbwEu/ 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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=EONOj0OHaUwSYU9N/VrCCNs20gpUnplCCd7yehPjBGA=; b=LhjLtXCfsK3VGfUO4AfpHlnEPe X1uCwNMrauYBDDYib0c8e1H/QCVfeUidDs6A38vLIgLRHoqWz5rwV+bEgdKJDtK+HIsrjU4qBmJJH ZCfA9iFiFyw8lnGKMXufzLrgAljdvReROBSItgsX4+T55OWadtZ+WZwCMDw8JEiJZfmHpLDoB07TX qCkHJpTcWqEjacn31ZJfC/neQvdW7pqGgkuoMOutEcqcfeeaUkaRfnJM/qXeEkwOYE8qNc/IORN4H 7tOqbYozN6D4l4TsrxbuiO5ony/Nh7KXaYo43kXhdvjh/1qtChxFz8i2k+HC356J661u2z88EgDyM 2rPTnmVA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xMOQv-000000094Nu-0gRH; Thu, 29 Oct 2026 11:36:37 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xMOQr-000000094NZ-0SsD for linux-arm-kernel@lists.infradead.org; Thu, 29 Oct 2026 11:36:35 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E03931BB2; Thu, 29 Oct 2026 04:36:25 -0700 (PDT) Received: from e143914.arm.com (e143914.arm.com [10.2.213.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7F6E83F59E; Thu, 29 Oct 2026 04:36:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1793273789; bh=dTGDCsCEyj7FTwEr3QOxyYhJdKuSWQypWjxORP+0gqw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KjZbwEu/7pDEST1UcOZipx4PNL9nNtV9k4JfrRVNhaXNfLarV45iCTWV4XZJHtYBg 7Qp8V4vg0BATp9y3eKpby/88Kdy0oRFzOenzdRcLRn8qQk5gAomlm+R8fdT7xSPCqV SKKx4Ybb/qFPlXDLhYwX4++/hczTt+/4/Xj4mTiw= Date: Thu, 29 Oct 2026 11:36:17 +0000 From: Joey Gouly To: Wei-Lin Chang Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, Marc Zyngier , Oliver Upton , Fuad Tabba , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Rutland , Jonathan Cameron , Mark Brown , Sascha Bischoff , James Clark , Lorenzo Pieralisi , Anshuman Khandual , Thomas Huth , Ganapatrao Kulkarni Subject: Re: [PATCH v2 3/4] KVM: arm64: Reset TCR_EL2 according to guest's E2H mode Message-ID: References: <20260917214215.74135-1-weilin.chang@arm.com> <20260917214215.74135-4-weilin.chang@arm.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260917214215.74135-4-weilin.chang@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261029_043633_278497_C5932B51 X-CRM114-Status: GOOD ( 19.04 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-15.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, Sep 17, 2026 at 10:42:13PM +0100, Wei-Lin Chang wrote: > From: Marc Zyngier > > Previously vCPU TCR_EL2's reset value didn't consider TCR_EL2's > different formats based on the value of HCR_EL2.E2H. It always resets to > the E2H == 0 version. > > This didn't cause any problem because the bits set in the E2H == 0 > version (TCR_EL2_RES1) all reset to UNKNOWN for E2H == 1 per the > architecture. > > Still, it's better to fix it. Choose the correct reset value by checking > KVM_ARM_VCPU_HAS_EL2_E2H0. > > Signed-off-by: Marc Zyngier > Signed-off-by: Wei-Lin Chang Reviewed-by: Joey Gouly > --- > arch/arm64/kvm/sys_regs.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index 44aae52c473d..62c059747fbb 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -3275,6 +3275,14 @@ static u64 reset_mdcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) > return vcpu->kvm->arch.nr_pmu_counters; > } > > +static u64 reset_tcr_el2(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) > +{ > + __vcpu_assign_sys_reg(vcpu, r->reg, > + vcpu_has_feature(vcpu, KVM_ARM_VCPU_HAS_EL2_E2H0) ? > + TCR_EL2_RES1 : VHE_TCR_EL2_RES1); > + return __vcpu_sys_reg(vcpu, r->reg); > +} > + > /* > * Architected system registers. > * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2 > @@ -3853,7 +3861,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { > > EL2_REG(TTBR0_EL2, access_rw, reset_val, 0), > EL2_REG(TTBR1_EL2, access_rw, reset_val, 0), > - EL2_REG(TCR_EL2, access_rw, reset_val, TCR_EL2_RES1), > + EL2_REG(TCR_EL2, access_rw, reset_tcr_el2, 0), > EL2_REG_FILTERED(TCR2_EL2, access_rw, reset_val, TCR2_EL2_RES1, > tcr2_el2_visibility), > EL2_REG_VNCR(VTTBR_EL2, reset_val, 0), > -- > 2.43.0 >