From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert VanVossen Subject: Re: 32-bit ARM guest on 64-bit ARM Xen Date: Wed, 29 Apr 2015 12:21:45 -0400 Message-ID: <55410519.4020009@dornerworks.com> References: <553FDC2B.1050306@dornerworks.com> <553FEA2F.6050306@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YnUlW-0006ax-Vr for xen-devel@lists.xenproject.org; Wed, 29 Apr 2015 16:23:15 +0000 In-Reply-To: <553FEA2F.6050306@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Julien Grall , xen-devel@lists.xenproject.org Cc: Ian Campbell List-Id: xen-devel@lists.xenproject.org On 4/28/2015 4:14 PM, Julien Grall wrote: > > On 28/04/2015 20:14, Robert VanVossen wrote: >> Hello, > > Hi Robert, > >> I was wondering, what is the current state of running a 32-bit ARM guest running >> on a 64-bit Xen for ARM. I was working on getting the minios from >> https://github.com/talex5/xen/commits/next built and running as a guest on an >> emulated Cortex-A53. I have gotten Xen and 64-bit Linux guests running in the >> emulated environment, but I ran into some issues with the 32-bit guests. > > I used 32-bit kernel on 64-bit hardware recently without no issue. > AFAICT, 32-bit guest as always worked on Xen. Which version on Xen are > you running? > I thought that should be the case, but I couldn't find confirmation anywhere online. I am building from master, more specifically commit 123c7793... > Also, silly question, does your hardware supports 32-bit instructions? > I.e were you able to run Linux 32-bit on baremetal? > I had assumed that all cortex-A53 implementations had to support 32-bit instructions, but that might not be the case. At least, the emulated model might not. I will have to look more into that. >> When I tried to run them, I got the following: >> >> Parsing config from /etc/xen/mini.cfg >> (XEN) Hypervisor Trap. HSR=0x2000000 EC=0x0 IL=1 Syndrome=0x0 > > This looks like an issue with Xen running on your hardware. EC = 0x0 > means "Exception with an Unkwnown reasons". > >> (XEN) CPU0: Unexpected Trap: Hypervisor >> (XEN) ----[ Xen-4.6-unstable arm64 debug=y Not tainted ]---- >> (XEN) CPU: 0 >> (XEN) PC: 00000000002413c8 schedule_tail+0x248/0x2dc > > schedule_tail contains the code to context switch from one domain to > another one. > > Can you run addr2line on the xen-syms with the address in PC and give > the result? > This yields xen/xen/arch/arm/domain.c:208 which has the following line: WRITE_SYSREG32(n->arch.teecr, TEECR32_EL1); Thanks, Robbie VanVossen