From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org by pdx-caf-mail.web.codeaurora.org (Dovecot) with LMTP id rj7LLpx6HlvVPwAAmS7hNA ; Mon, 11 Jun 2018 13:36:51 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 7CE1D607BB; Mon, 11 Jun 2018 13:36:51 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by smtp.codeaurora.org (Postfix) with ESMTP id 01E0460541; Mon, 11 Jun 2018 13:36:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 01E0460541 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933352AbeFKNgu (ORCPT + 19 others); Mon, 11 Jun 2018 09:36:50 -0400 Received: from foss.arm.com ([217.140.101.70]:51680 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754238AbeFKNgq (ORCPT ); Mon, 11 Jun 2018 09:36:46 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D22141596; Mon, 11 Jun 2018 06:36:45 -0700 (PDT) Received: from [10.1.206.34] (melchizedek.cambridge.arm.com [10.1.206.34]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BF6B53F318; Mon, 11 Jun 2018 06:36:43 -0700 (PDT) Subject: Re: [PATCH RESEND v4 2/2] arm/arm64: KVM: Add KVM_GET/SET_VCPU_EVENTS To: Marc Zyngier , Dongjiu Geng Cc: rkrcmar@redhat.com, corbet@lwn.net, christoffer.dall@arm.com, linux@armlinux.org.uk, catalin.marinas@arm.com, will.deacon@arm.com, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org References: <1528487320-2873-1-git-send-email-gengdongjiu@huawei.com> <1528487320-2873-3-git-send-email-gengdongjiu@huawei.com> <86zi04875t.wl-marc.zyngier@arm.com> From: James Morse Message-ID: Date: Mon, 11 Jun 2018 14:36:42 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <86zi04875t.wl-marc.zyngier@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Dongjiu Geng, On 09/06/18 13:40, Marc Zyngier wrote: > On Fri, 08 Jun 2018 20:48:40 +0100, Dongjiu Geng wrote: >> For the migrating VMs, user space may need to know the exception >> state. For example, in the machine A, KVM make an SError pending, >> when migrate to B, KVM also needs to pend an SError. >> >> This new IOCTL exports user-invisible states related to SError. >> Together with appropriate user space changes, user space can get/set >> the SError exception state to do migrate/snapshot/suspend. >> diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h >> index 04b3256..df4faee 100644 >> --- a/arch/arm64/include/uapi/asm/kvm.h >> +++ b/arch/arm64/include/uapi/asm/kvm.h >> @@ -153,6 +154,18 @@ struct kvm_sync_regs { >> struct kvm_arch_memory_slot { >> }; >> >> +/* for KVM_GET/SET_VCPU_EVENTS */ >> +struct kvm_vcpu_events { >> + struct { >> + __u8 serror_pending; >> + __u8 serror_has_esr; >> + /* Align it to 8 bytes */ >> + __u8 pad[6]; >> + __u64 serror_esr; >> + } exception; >> + __u32 reserved[12]; >> +}; >> diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c >> index 56a0260..4426915 100644 >> --- a/arch/arm64/kvm/guest.c >> +++ b/arch/arm64/kvm/guest.c >> +int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, >> + struct kvm_vcpu_events *events) >> +{ >> + bool serror_pending = events->exception.serror_pending; >> + bool has_esr = events->exception.serror_has_esr; >> + >> + if (serror_pending && has_esr) { >> + if (!cpus_have_const_cap(ARM64_HAS_RAS_EXTN)) >> + return -EINVAL; >> + >> + kvm_set_sei_esr(vcpu, events->exception.serror_esr); >> + } else if (serror_pending) { >> + kvm_inject_vabt(vcpu); >> + } >> + >> + return 0; > > There was an earlier request to check that all the padding is set to > zero. I still think this makes sense. I agree, not just the exception.padding[], but reserved[] too. Thanks, James