From patchwork Mon Nov 28 11:59:15 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 84383 Delivered-To: patch@linaro.org Received: by 10.182.1.168 with SMTP id 8csp1599961obn; Mon, 28 Nov 2016 03:59:34 -0800 (PST) X-Received: by 10.99.37.195 with SMTP id l186mr38613960pgl.91.1480334374876; Mon, 28 Nov 2016 03:59:34 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id b19si54916874pfc.24.2016.11.28.03.59.34; Mon, 28 Nov 2016 03:59:34 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754236AbcK1L7Z (ORCPT + 25 others); Mon, 28 Nov 2016 06:59:25 -0500 Received: from foss.arm.com ([217.140.101.70]:50412 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932094AbcK1L7T (ORCPT ); Mon, 28 Nov 2016 06:59:19 -0500 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 926ECAD7; Mon, 28 Nov 2016 03:59:18 -0800 (PST) Received: from [10.1.218.32] (e108454-lin.cambridge.arm.com [10.1.218.32]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 072B73F445; Mon, 28 Nov 2016 03:59:16 -0800 (PST) Subject: Re: Kernel Panics on Xen ARM64 for Domain0 and Guest To: Wei Chen , "tj@kernel.org" , "zijun_hu@htc.com" References: Cc: "cl@linux.com" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xenproject.org" , Kaly Xin , Steve Capper , Stefano Stabellini From: Julien Grall Message-ID: <420a44c0-f86f-e6ab-44af-93ada7e01b58@arm.com> Date: Mon, 28 Nov 2016 11:59:15 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28/11/16 09:38, Wei Chen wrote: > Hi, Hi Wei, > I have found a commit in "PER-CPU MEMORY ALLOCATOR" will panic the > kernels that are runing on ARM64 Xen (include Domain0 and Guest). > > commit 3ca45a46f8af8c4a92dd8a08eac57787242d5021 > percpu: ensure the requested alignment is power of two It would have been useful to specify the tree used. In this case, this commit comes from linux-next. > > If I revert this commit, the Kernels can work properly on ARM64 Xen. > > The following is the log: Please try to copy the full log as the crash may be a consequence of another error. I gave a try and there was a warning ([1]) just before which lead to the crash afterwards. This is because of the call to __alloc_percpu in xen_guest_init returns NULL due to: "illegal size (48) or align (48) for percpu allocation" I think the best way to fix it is: I will send proper patch later. Cheers, [1] [ 0.023921] illegal size (48) or align (48) for percpu allocation [ 0.024167] ------------[ cut here ]------------ [ 0.024344] WARNING: CPU: 0 PID: 1 at linux/mm/percpu.c:892 pcpu_alloc+0x88/0x6c0 [ 0.024584] Modules linked in: [ 0.024708] [ 0.024804] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.0-rc7-next-20161128 #473 [ 0.025012] Hardware name: Foundation-v8A (DT) [ 0.025162] task: ffff80003d870000 task.stack: ffff80003d844000 [ 0.025351] PC is at pcpu_alloc+0x88/0x6c0 [ 0.025490] LR is at pcpu_alloc+0x88/0x6c0 [ 0.025624] pc : [] lr : [] pstate: 60000045 [ 0.025830] sp : ffff80003d847cd0 [ 0.025946] x29: ffff80003d847cd0 x28: 0000000000000000 [ 0.026147] x27: 0000000000000000 x26: 0000000000000000 [ 0.026348] x25: 0000000000000000 x24: 0000000000000000 [ 0.026549] x23: 0000000000000000 x22: 00000000024000c0 [ 0.026752] x21: ffff000008e97000 x20: 0000000000000000 [ 0.026953] x19: 0000000000000030 x18: 0000000000000010 [ 0.027155] x17: 0000000000000a3f x16: 00000000deadbeef [ 0.027357] x15: 0000000000000006 x14: ffff000088f79c3f [ 0.027573] x13: ffff000008f79c4d x12: 0000000000000041 [ 0.027782] x11: 0000000000000006 x10: 0000000000000042 [ 0.027995] x9 : ffff80003d847a40 x8 : 6f697461636f6c6c [ 0.028208] x7 : 6120757063726570 x6 : ffff000008f79c84 [ 0.028419] x5 : 0000000000000005 x4 : 0000000000000000 [ 0.028628] x3 : 0000000000000000 x2 : 000000000000017f [ 0.028840] x1 : ffff80003d870000 x0 : 0000000000000035 [ 0.029056] [ 0.029152] ---[ end trace 0000000000000000 ]--- [ 0.029297] Call trace: [ 0.029403] Exception stack(0xffff80003d847b00 to 0xffff80003d847c30) [ 0.029621] 7b00: 0000000000000030 0001000000000000 ffff80003d847cd0 ffff00000818e678 [ 0.029901] 7b20: 0000000000000002 0000000000000004 ffff000008f7c060 0000000000000035 [ 0.030153] 7b40: ffff000008f79000 ffff000008c4cd88 ffff80003d847bf0 ffff000008101778 [ 0.030402] 7b60: 0000000000000030 0000000000000000 ffff000008e97000 00000000024000c0 [ 0.030647] 7b80: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 0.030895] 7ba0: 0000000000000035 ffff80003d870000 000000000000017f 0000000000000000 [ 0.031144] 7bc0: 0000000000000000 0000000000000005 ffff000008f79c84 6120757063726570 [ 0.031394] 7be0: 6f697461636f6c6c ffff80003d847a40 0000000000000042 0000000000000006 [ 0.031643] 7c00: 0000000000000041 ffff000008f79c4d ffff000088f79c3f 0000000000000006 [ 0.031877] 7c20: 00000000deadbeef 0000000000000a3f [ 0.032051] [] pcpu_alloc+0x88/0x6c0 [ 0.032229] [] __alloc_percpu+0x18/0x20 [ 0.032409] [] xen_guest_init+0x174/0x2f4 [ 0.032591] [] do_one_initcall+0x38/0x130 [ 0.032783] [] kernel_init_freeable+0xe0/0x248 [ 0.032995] [] kernel_init+0x10/0x100 [ 0.033172] [] ret_from_fork+0x10/0x50 -- Julien Grall diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index f193414..4986dc0 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -372,8 +372,7 @@ static int __init xen_guest_init(void) * for secondary CPUs as they are brought up. * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. */ - xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info), - sizeof(struct vcpu_info)); + xen_vcpu_info = alloc_percpu(struct vcpu_info); if (xen_vcpu_info == NULL) return -ENOMEM;