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dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52554 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kVJjQ-0003tQ-9G for qemu-devel@archiver.kernel.org; Wed, 21 Oct 2020 15:25:08 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45094) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kVJPA-0003Z3-KR for qemu-devel@nongnu.org; Wed, 21 Oct 2020 15:04:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:50531) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kVJP8-0000zo-J3 for qemu-devel@nongnu.org; Wed, 21 Oct 2020 15:04:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603307048; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; 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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=alex.williamson@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=alex.williamson@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/20 22:12:28 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=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: cohuck@redhat.com, cjia@nvidia.com, aik@ozlabs.ru, Zhengxiao.zx@Alibaba-inc.com, shuangtai.tst@alibaba-inc.com, qemu-devel@nongnu.org, peterx@redhat.com, Kirti Wankhede , eauger@redhat.com, yi.l.liu@intel.com, eskultet@redhat.com, ziye.yang@intel.com, armbru@redhat.com, mlevitsk@redhat.com, pasic@linux.ibm.com, felipe@nutanix.com, wanghaibin.wang@huawei.com, zhi.a.wang@intel.com, kevin.tian@intel.com, yan.y.zhao@intel.com, dgilbert@redhat.com, changpeng.liu@intel.com, quintela@redhat.com, lushenming@huawei.com, Ken.Xue@amd.com, jonathan.davies@nutanix.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, 21 Oct 2020 17:30:04 +0800 Zenghui Yu wrote: > On 2020/9/25 6:49, Alex Williamson wrote: > >> + } else if (interrupt_type == VFIO_INT_MSIX) { > >> + uint16_t offset; > >> + > >> + msix_load(pdev, f); > >> + offset = pci_default_read_config(pdev, > >> + pdev->msix_cap + PCI_MSIX_FLAGS + 1, 2); > >> + /* load enable bit and maskall bit */ > >> + vfio_pci_write_config(pdev, pdev->msix_cap + PCI_MSIX_FLAGS + 1, > >> + offset, 2); > > It isn't clear that what purpose this load operation serves. The config > space has already been restored and we'll see that MSI-X _was_ and _is_ > enabled (or disabled). vfio_msix_enable() will therefore not be invoked > and no vectors would actually be enabled... Not sure if I had missed > something. Yeah, afaict your interpretation is correct. I think the intention was to mimic userspace preforming a write to set the enable bit, but re-writing it doesn't change the vconfig value, so the effect is not the same. I think this probably never worked. > >> + } > >> + return 0; > > > > It seems this could be simplified down to: > > > > if (msi_enabled(pdev)) { > > vfio_msi_enable(vdev); > > } else if (msix_enabled(pdev)) { > > msix_load(pdev, f); > > vfio_msix_enable(vdev); > > } > > And it seems that this has fixed something :-) Yep, no dependency on the value changing, simply set the state to that indicated in vconfig. Thanks, Alex