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Wed, 8 Nov 2023 16:52:28 +0000 Received: from SJ2PR11MB7573.namprd11.prod.outlook.com ([fe80::6710:537d:b74:f1e5]) by SJ2PR11MB7573.namprd11.prod.outlook.com ([fe80::6710:537d:b74:f1e5%5]) with mapi id 15.20.6954.029; Wed, 8 Nov 2023 16:52:28 +0000 Message-ID: <48b8a6ae-6275-40ca-9db0-86b96cb002de@intel.com> Date: Wed, 8 Nov 2023 08:52:25 -0800 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH V3 00/26] vfio/pci: Back guest interrupts from Interrupt Message Store (IMS) Content-Language: en-US To: Alex Williamson CC: "Tian, Kevin" , "jgg@nvidia.com" , "yishaih@nvidia.com" , "shameerali.kolothum.thodi@huawei.com" , "kvm@vger.kernel.org" , "Jiang, Dave" , "Liu, Jing2" , "Raj, Ashok" , "Yu, Fenghua" , "tom.zanussi@linux.intel.com" , "linux-kernel@vger.kernel.org" , "patches@lists.linux.dev" References: <20231101120714.7763ed35.alex.williamson@redhat.com> <20231102151352.1731de78.alex.williamson@redhat.com> <20231103095119.63aa796f.alex.williamson@redhat.com> <7f8b89c7-7ae0-4f2d-9e46-e15a6db7f6d9@intel.com> <20231107160641.45aee2e0.alex.williamson@redhat.com> From: Reinette Chatre In-Reply-To: <20231107160641.45aee2e0.alex.williamson@redhat.com> Content-Type: text/plain; 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Meanwhile I think the goal is to reduce > complication to a driver that doesn't exist yet. So it currently seems > like a poor trade-off. > > This driver that doesn't exist yet could implement its own SET_IRQS > ioctl that backs MSI-X with IMS as a starting point. Presumably we > expect multiple drivers to require this behavior, so common code makes > sense, but the rest of us in the community can't really evaluate how > much it makes sense to slice the common code without seeing that > implementation and how it might leverage, if not directly use, the > existing core code. I understand. I'm hearing the same from you and Jason. I plan to work on addressing your feedback but will only share it when it can be accompanied by a draft of the IDXD VDCM driver. Please let me know if you prefer a different approach. Reinette