From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3307C43BDAC; Tue, 4 Aug 2026 08:57:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785833834; cv=none; b=i9Xq/2Wj0sXCXMRb46DbE7494Sr5Is+fSczGagxSJx9a1bgc33KZm4GdB/QOS6RLhMUkx41EIOd6I8zn4RENBCMDvL1o41Is6zJaIWG/Ek7V4cwgrakyEUJRJl/+xLbT0vPmrH6OtZwk8WruXhW0GHpxc4QzpVP+QIWyOzEWFcw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785833834; c=relaxed/simple; bh=EWmgbJlVXftcAZw8ONc8X9BQ1H09O3p9MgB5FgvLadc=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=jiipUW5ugDI008w0jlvAziF/EPyAC9ueH0HE/1ciom9OVgGQM/fL8xSSl1wF9SkA83JDhfLdEgr1K0McQ8cZ0jvWJ+z2vu2YpAWgAfMArbc+37+GZMKlcPCDfM2wg56rvnFbOlrgRPPnwljb19KLWpdI6zni2Vr6dDnGldehUHI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UT90DsPz; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UT90DsPz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28E3A1F000E9; Tue, 4 Aug 2026 08:57:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785833832; bh=xxS0NRBY3i0kZcuHxe0V5BgtVYZZ3/0KR07GPgwzac4=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=UT90DsPzrSuia1XzFFet3nOueTooswWOFwwvIVVUp4i31U91QcZdNkPS7wDN44WfZ 5SW8BtiDJsI6Fx9pak/IUmX5Z2J+CsBdP8wwjY3f2mQUM4eQIABFyJaXxGJhayR1gn U5R+0MEmOP50TZcTUR7p1eCgQVGCvP9a8smRHHuChY1zUBlFlrNOJSODIP4Z9/TPfi uBn3/pDxKsMyP6756Kk1ACB4f53ti49Pq6U7ezDbTVRR4O1TOTd6/BFPY6zByPR6tj IFWmH0hMFRtARMPxU/r8zriH6wy2JEQQcyViZK2NO2uukW7vthHJI/O6clzH5elLoU 7Nyp9EMGnWMEA== X-Mailer: emacs 30.2 (via feedmail 11-beta-1 I) From: Aneesh Kumar K.V To: Steven Price , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , Emi Kisanuki , Vishal Annapurve , WeiLin.Chang@arm.com, Lorenzo Pieralisi Subject: Re: [PATCH v16 21/45] KVM: arm64: CCA: Handle realm enter/exit In-Reply-To: <20260803134403.80630-22-steven.price@arm.com> References: <20260803134403.80630-1-steven.price@arm.com> <20260803134403.80630-22-steven.price@arm.com> Date: Tue, 04 Aug 2026 14:27:03 +0530 Message-ID: Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Steven Price writes: > + switch (rec->run->exit.exit_reason) { > + case RMI_EXIT_SYNC: > + /* > + * HPFAR_EL2_NS is hijacked to indicate a valid HPFAR value, > + * see __get_fault_info() > + */ > + vcpu->arch.fault.hpfar_el2 = rec->run->exit.hpfar | HPFAR_EL2_NS; > + rec_exit_sync(vcpu); > + return ARM_EXCEPTION_TRAP; > + case RMI_EXIT_IRQ: > + case RMI_EXIT_FIQ: > + return ARM_EXCEPTION_IRQ; > + case RMI_EXIT_SERROR: > + return ARM_EXCEPTION_EL1_SERROR; > + case RMI_EXIT_PSCI: > + rec_exit_hvc(vcpu); > + kvm_make_request(KVM_REQ_RMI, vcpu); > + return ARM_EXCEPTION_TRAP; > + case RMI_EXIT_RIPAS_CHANGE: > + rec_exit_hvc(vcpu); > + return ARM_EXCEPTION_TRAP; > + } Should we handle RMI_EXIT_RIPAS_CHANGE differently? Currently, the call path is: kvm_rec_exit() -> RMI_EXIT_RIPAS_CHANGE -> handle_hvc() -> kvm_rec_handle_hvc() -> kvm_prepare_memory_fault_exit() Could we instead treat RMI_EXIT_RIPAS_CHANGE as a special case and avoid redirecting it through handle_hvc()? The completion part of the RIPAS change could still be handled by kvm_rec_handle_request(). -bool kvm_rec_handle_hvc(struct kvm_vcpu *vcpu, int *ret) +static int rec_exit_ripas_change(struct kvm_vcpu *vcpu) { - struct realm_rec *rec; + struct realm_rec *rec = &vcpu->arch.rec; struct realm *realm; unsigned long base; unsigned long ripas; unsigned long top; - if (!vcpu_is_rec(vcpu)) - return false; - - rec = &vcpu->arch.rec; - if (rec->run->exit.exit_reason != RMI_EXIT_RIPAS_CHANGE) - return false; - realm = &vcpu->kvm->arch.realm; base = rec->run->exit.ripas_base; top = rec->run->exit.ripas_top; @@ -89,8 +83,7 @@ bool kvm_rec_handle_hvc(struct kvm_vcpu *vcpu, int *ret) base, top, ripas); /* Set RMI_REJECT bit */ rec->run->enter.flags = REC_ENTER_FLAG_RIPAS_RESPONSE; - *ret = -EINVAL; - return true; + return -EINVAL; } /* Exit to VMM, the actual RIPAS change is done on next entry */ @@ -102,8 +95,7 @@ bool kvm_rec_handle_hvc(struct kvm_vcpu *vcpu, int *ret) * KVM_EXIT_MEMORY_FAULT requires a return code of -EFAULT, see the * API documentation */ - *ret = -EFAULT; - return true; + return -EFAULT; } int kvm_rec_exit(struct kvm_vcpu *vcpu, int rec_run_ret) @@ -169,8 +161,7 @@ int kvm_rec_exit(struct kvm_vcpu *vcpu, int rec_run_ret) kvm_make_request(KVM_REQ_RMI, vcpu); return ARM_EXCEPTION_TRAP; case RMI_EXIT_RIPAS_CHANGE: - rec_exit_hvc(vcpu); - return ARM_EXCEPTION_TRAP; + return rec_exit_ripas_change(vcpu); } return rec_exit_fatal(vcpu, "Unsupported Realm exit reason", -aneesh