From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 82808C433DB for ; Fri, 19 Feb 2021 10:34:42 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E521A64DED for ; Fri, 19 Feb 2021 10:34:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E521A64DED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35260 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lD37Q-0006Ty-Of for qemu-devel@archiver.kernel.org; Fri, 19 Feb 2021 05:34:40 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:33520) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lD36O-0005cp-DI; Fri, 19 Feb 2021 05:33:36 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:3311) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lD36L-0003n8-DN; Fri, 19 Feb 2021 05:33:36 -0500 Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4DhntP4Cv8zlMkd; Fri, 19 Feb 2021 18:31:25 +0800 (CST) Received: from [10.174.184.135] (10.174.184.135) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.498.0; Fri, 19 Feb 2021 18:33:14 +0800 Subject: Re: [RFC PATCH v2 1/3] vfio: Move the saving of the config space to the right place in VFIO migration To: Kirti Wankhede , Alex Williamson References: <20201209080919.156-1-lushenming@huawei.com> <20201209080919.156-2-lushenming@huawei.com> From: Shenming Lu Message-ID: Date: Fri, 19 Feb 2021 18:33:03 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.2.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.184.135] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.190; envelope-from=lushenming@huawei.com; helo=szxga04-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Lorenzo Pieralisi , Neo Jia , mst@redhat.com, Marc Zyngier , Cornelia Huck , qemu-devel@nongnu.org, "Dr . David Alan Gilbert" , Eric Auger , qemu-arm@nongnu.org, yuzenghui@huawei.com, wanghaibin.wang@huawei.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2021/2/18 22:42, Kirti Wankhede wrote: > > > On 12/9/2020 1:39 PM, Shenming Lu wrote: >> On ARM64 the VFIO SET_IRQS ioctl is dependent on the VM interrupt >> setup, if the restoring of the VFIO PCI device config space is >> before the VGIC, an error might occur in the kernel. >> >> So we move the saving of the config space to the non-iterable >> process, so that it will be called after the VGIC according to >> their priorities. >> >> As for the possible dependence of the device specific migration >> data on it's config space, we can let the vendor driver to >> include any config info it needs in its own data stream. >> (Should we note this in the header file linux-headers/linux/vfio.h?) >> >> Signed-off-by: Shenming Lu >> --- >>   hw/vfio/migration.c | 25 +++++++++++++++---------- >>   1 file changed, 15 insertions(+), 10 deletions(-) >> >> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c >> index 00daa50ed8..3b9de1353a 100644 >> --- a/hw/vfio/migration.c >> +++ b/hw/vfio/migration.c >> @@ -575,11 +575,6 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) >>           return ret; >>       } >>   -    ret = vfio_save_device_config_state(f, opaque); >> -    if (ret) { >> -        return ret; >> -    } >> - >>       ret = vfio_update_pending(vbasedev); >>       if (ret) { >>           return ret; >> @@ -620,6 +615,19 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) >>       return ret; >>   } >>   +static void vfio_save_state(QEMUFile *f, void *opaque) >> +{ >> +    VFIODevice *vbasedev = opaque; >> +    int ret; >> + >> +    /* The device specific data is migrated in the iterable process. */ >> +    ret = vfio_save_device_config_state(f, opaque); >> +    if (ret) { >> +        error_report("%s: Failed to save device config space", >> +                     vbasedev->name); >> +    } >> +} >> + > > Since error is not propagated, set error in migration stream for migration to fail, use qemu_file_set_error() on error. Makes sense. I will send a v3 soon. Thanks, Shenming > > Thanks, > Kirti > >>   static int vfio_load_setup(QEMUFile *f, void *opaque) >>   { >>       VFIODevice *vbasedev = opaque; >> @@ -670,11 +678,7 @@ static int vfio_load_state(QEMUFile *f, void *opaque, int version_id) >>           switch (data) { >>           case VFIO_MIG_FLAG_DEV_CONFIG_STATE: >>           { >> -            ret = vfio_load_device_config_state(f, opaque); >> -            if (ret) { >> -                return ret; >> -            } >> -            break; >> +            return vfio_load_device_config_state(f, opaque); >>           } >>           case VFIO_MIG_FLAG_DEV_SETUP_STATE: >>           { >> @@ -720,6 +724,7 @@ static SaveVMHandlers savevm_vfio_handlers = { >>       .save_live_pending = vfio_save_pending, >>       .save_live_iterate = vfio_save_iterate, >>       .save_live_complete_precopy = vfio_save_complete_precopy, >> +    .save_state = vfio_save_state, >>       .load_setup = vfio_load_setup, >>       .load_cleanup = vfio_load_cleanup, >>       .load_state = vfio_load_state, >> > .