From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934426AbdKBU1J (ORCPT ); Thu, 2 Nov 2017 16:27:09 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:23291 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932241AbdKBU1G (ORCPT ); Thu, 2 Nov 2017 16:27:06 -0400 Subject: Re: [PATCH v6 1/1] xen/time: do not decrease steal time after live migration on xen To: Dongli Zhang , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org References: <1509500793-9896-1-git-send-email-dongli.zhang@oracle.com> Cc: jgross@suse.com, joao.m.martins@oracle.com From: Boris Ostrovsky Message-ID: <95598986-2888-2784-8737-0aaa6991c728@oracle.com> Date: Thu, 2 Nov 2017 16:28:31 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/01/2017 09:19 PM, Dongli Zhang wrote: > Hi Boris, > > I have received from lkp@intel.com that the prior version of patch hit issue > during compilation with aarch64-linux-gnu-gcc. I think this patch reviewed by > you would hit the same compiling issue on arm64 (there is no issue with x86_64). > > ------------------------------------------------------------- > > 1st issue: > > Without including header into driver/xen/time.c, compilation on > x86_64 works well (without any warning or error) but arm64 would hit the > following error: > > drivers/xen/time.c: In function ‘xen_manage_runstate_time’: > drivers/xen/time.c:94:20: error: implicit declaration of function > ‘kmalloc_array’ [-Werror=implicit-function-declaration] > runstate_delta = kmalloc_array(num_possible_cpus(), > ^ > > drivers/xen/time.c:131:3: error: implicit declaration of function ‘kfree’ > [-Werror=implicit-function-declaration] > kfree(runstate_delta); > ^ > cc1: some warnings being treated as errors > > About the 1st issue, should I submit a new patch including or > just a incremental based on previous patch merged into your own branch > /tree? > > ------------------------------------------------------------- > > 2nd issue: > > aarch64-linux-gnu-gcc expects a cast for kmalloc_array(). Is this really > necessary as I did find people casting the return type of > kmalloc/kcalloc/kmalloc_array in linux source code (e.g., > drivers/block/virtio_blk.c). Can we just ignore this warning? > > drivers/xen/time.c:94:18: warning: assignment makes pointer from integer without > a cast [-Wint-conversion] > runstate_delta = kmalloc_array(num_possible_cpus(), > ^ > ------------------------------------------------------------- That's because you need to declare kmalloc_array(), otherwise the compiler by default assumes that it returns an int. So including linux/slab.h should take care of both warnings. I can add it while committing. -boris