From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Morse Subject: Re: [PATCH v6 5/7] arm64: kvm: route synchronous external abort exceptions to el2 Date: Mon, 16 Oct 2017 12:44:56 +0100 Message-ID: <59E49BB8.8080801@arm.com> References: <1503916701-13516-1-git-send-email-gengdongjiu@huawei.com> <1503916701-13516-6-git-send-email-gengdongjiu@huawei.com> <59B17449.6010201@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: christoffer.dall@linaro.org, marc.zyngier@arm.com, rkrcmar@redhat.com, linux@armlinux.org.uk, catalin.marinas@arm.com, will.deacon@arm.com, lenb@kernel.org, robert.moore@intel.com, lv.zheng@intel.com, mark.rutland@arm.com, xiexiuqi@huawei.com, cov@codeaurora.org, david.daney@cavium.com, suzuki.poulose@arm.com, stefan@hello-penguin.com, Dave.Martin@arm.com, kristina.martsenko@arm.com, wangkefeng.wang@huawei.com, tbaicar@codeaurora.org, ard.biesheuvel@linaro.org, mingo@kernel.org, bp@suse.de, shiju.jose@huawei.com, zjzhang@codeaurora.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, devel@acpica.org, mst@redhat.com, john.garry@huawei.com, jonathan.cameron@huawei.com, shameerali.kolot To: gengdongjiu Return-path: In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Hi gengdongjiu, On 14/09/17 12:12, gengdongjiu wrote: > On 2017/9/8 0:31, James Morse wrote: >> KVM already handles external aborts from lower exception levels, no more work >> needs doing for TEA. > If it is firmware first solution, that is SCR_EL3.EA=1, all SError interrupt and synchronous External > Abort exceptions are taken to EL3, so EL3 firmware will handle it, KVM no needs to handle it. > > HCR_EL3.TEA is only for EL3 to check its value to decide to jump to hypervisor or kernel. > >> >> What happens when a guest access the RAS-Error-Record registers? >> >> Before we can set HCR_EL2.TERR I think we need to add some minimal emulation for >> the registers it traps. Most of them should be RAZ/WI, so it should be >> straightforward. (I think KVMs default is to emulate an undef for unknown traps). > Today I added the support to do some minimal emulation for RAS-Error-Record registers, thanks > for the good suggestion. Where can I find this patch? I'd like to repost it as part of the SError_rework/RAS/IESB series: this is one of the bits KVM needs but I didn't touch as it looks like your updated version of this patch should cover it. Thanks, James