From patchwork Mon Feb 10 18:41:34 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13969050 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 57082C021A1 for ; Mon, 10 Feb 2025 19:35:05 +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=u5Zipbgwa7d3CHqvlSPNv1XmueDzqzI7rgtCnBI8lE8=; b=tDQQv3i/haPaTRyNNblIrJrX4S q/cfGGi22aKef2xU2Gh50iyOalC8lKih2c4IZLJd4ixTWqOEoXp0RB1ffmastkWa/L0ov0E2re+Ss ExTDYCQ9ycyTOwUZhVSF9WuhnKG5BY7stw7BZAVJTn5wtRaDmu0VdBIQr3tPR0T4zObWwKbn30AsL 8V1Qq8KqTbrMUbi2WacGdbz1lROqSYUfkyE7SC3u2fQ9gM+ioawJ5IBwZ1JwpuY5+n0xHwr4h2Chb mxg4UsS1YYkV6rF5lrFQVRF2ctC5cwTg9wUw+xlu90JQP2A5cFN1qWAb2dKwKAg2iZxWfviaaDzjw eGrb7Wtg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1thZYV-000000016Xa-3eyA; Mon, 10 Feb 2025 19:34:55 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1thYjI-00000000yrx-3hPS for linux-arm-kernel@lists.infradead.org; Mon, 10 Feb 2025 18:42:02 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id C831E5C5DED; Mon, 10 Feb 2025 18:41:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D171C4CEE8; Mon, 10 Feb 2025 18:42:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739212920; bh=Wi2tx+wpbCR4WtycbeYLZhI3AsgEkM8AXxOTe1vY7yU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UuIENE/6RVcsxFzRVQL2ldgYzZPpnFVWpmdBtuN4lS/qbsrAXpE6wXAUhstvPAkEz qg/IYjlYwLfoFIGcANHmCNNwKpo/IFityJ+0WZJ3ugr5P2YQQQuFHFYGiJhIsNuQ22 1iv91cixOaLkDTjHfUM5P/Va0FdX/dbhbcaIf/LNnEsnKWRMa5fH9JAgylZKz7hgxb iaLEmjc8hDqNfIYs/9JjbJHnoKPqZZMlkhdzOG/9UpLxZgO1x6cZnyp3LolcXr9c9w Ij/KHAFcfiSDCJ5Q9DkM0SRJ5vuCmzlkiHdpbhRaFRggiVSnCNA9d1gsIvSbGhNFfQ OJS3w0RCjDZ6g== 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 4.95) (envelope-from ) id 1thYjF-002g2I-S7; Mon, 10 Feb 2025 18:41:57 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Mark Rutland , Fuad Tabba Subject: [PATCH 03/18] KVM: arm64: Handle trapping of FEAT_LS64* instructions Date: Mon, 10 Feb 2025 18:41:34 +0000 Message-Id: <20250210184150.2145093-4-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250210184150.2145093-1-maz@kernel.org> References: <20250210184150.2145093-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, joey.gouly@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, mark.rutland@arm.com, tabba@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250210_104201_017903_A3320A9C X-CRM114-Status: GOOD ( 13.34 ) 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 We generally don't expect FEAT_LS64* instructions to trap, unless they are trapped by a guest hypervisor. Otherwise, this is just the guest playing tricks on us by using an instruction that isn't advertised, which we handle with a well deserved UNDEF. Signed-off-by: Marc Zyngier --- arch/arm64/kvm/handle_exit.c | 64 ++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 512d152233ff2..4f8354bf7dc5f 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -294,6 +294,69 @@ static int handle_svc(struct kvm_vcpu *vcpu) return 1; } +static int handle_ls64b(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + u64 esr = kvm_vcpu_get_esr(vcpu); + u64 iss = ESR_ELx_ISS(esr); + bool allowed; + + switch (iss) { + case ESR_ELx_ISS_ST64BV: + allowed = kvm_has_feat(kvm, ID_AA64ISAR1_EL1, LS64, LS64_V); + break; + case ESR_ELx_ISS_ST64BV0: + allowed = kvm_has_feat(kvm, ID_AA64ISAR1_EL1, LS64, LS64_ACCDATA); + break; + case ESR_ELx_ISS_LDST64B: + allowed = kvm_has_feat(kvm, ID_AA64ISAR1_EL1, LS64, LS64); + break; + default: + /* Clearly, we're missing something. */ + goto unknown_trap; + } + + if (!allowed) + goto undef; + + if (vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) { + u64 hcrx = __vcpu_sys_reg(vcpu, HCRX_EL2); + bool fwd; + + switch (iss) { + case ESR_ELx_ISS_ST64BV: + fwd = !(hcrx & HCRX_EL2_EnASR); + break; + case ESR_ELx_ISS_ST64BV0: + fwd = !(hcrx & HCRX_EL2_EnAS0); + break; + case ESR_ELx_ISS_LDST64B: + fwd = !(hcrx & HCRX_EL2_EnALS); + break; + default: + /* We don't expect to be here */ + fwd = false; + } + + if (fwd) { + kvm_inject_nested_sync(vcpu, esr); + return 1; + } + } + +unknown_trap: + /* + * If we land here, something must be very wrong, because we + * have no idea why we trapped at all. Warn and undef as a + * fallback. + */ + WARN_ON(1); + +undef: + kvm_inject_undefined(vcpu); + return 1; +} + static exit_handle_fn arm_exit_handlers[] = { [0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec, [ESR_ELx_EC_WFx] = kvm_handle_wfx, @@ -303,6 +366,7 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_CP14_LS] = kvm_handle_cp14_load_store, [ESR_ELx_EC_CP10_ID] = kvm_handle_cp10_id, [ESR_ELx_EC_CP14_64] = kvm_handle_cp14_64, + [ESR_ELx_EC_LS64B] = handle_ls64b, [ESR_ELx_EC_HVC32] = handle_hvc, [ESR_ELx_EC_SMC32] = handle_smc, [ESR_ELx_EC_HVC64] = handle_hvc,