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b=fgYvRyw5h3/HT2ZxbMOrUG4ZCsWxVZ9wfPD2j9APBv691AZqa2HQ2i6hcisd9+wiq5o8bF+buOFN3OPcUn80d03COO/a0wJln8pBW41xuc1SDch7cGVzWIlgorSYYY50Mq4EbjjbKYvaS7NaWRjSrtdNwggiOIL0dsQVC57nV/I= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from CH2PR12MB4199.namprd12.prod.outlook.com (2603:10b6:610:a7::13) by SA3PR12MB9107.namprd12.prod.outlook.com (2603:10b6:806:381::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9913.11; Wed, 13 May 2026 18:19:07 +0000 Received: from CH2PR12MB4199.namprd12.prod.outlook.com ([fe80::cc19:be83:4f32:d44b]) by CH2PR12MB4199.namprd12.prod.outlook.com ([fe80::cc19:be83:4f32:d44b%6]) with mapi id 15.20.9913.009; Wed, 13 May 2026 18:19:06 +0000 Message-ID: <6bcb82bb-5306-4448-8a59-6141c2dc5ea2@amd.com> Date: Wed, 13 May 2026 19:19:02 +0100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v26 7/8] cxl: Avoid dax creation for accelerators Content-Language: en-US To: Alison Schofield , alejandro.lucero-palau@amd.com Cc: linux-cxl@vger.kernel.org, djbw@kernel.org, edward.cree@amd.com, davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, dave.jiang@intel.com, Jonathan Cameron , Davidlohr Bueso , Ben Cheatham References: <20260423180528.17166-1-alejandro.lucero-palau@amd.com> <20260423180528.17166-8-alejandro.lucero-palau@amd.com> From: Alejandro Lucero Palau In-Reply-To: Content-Type: text/plain; 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>> >> + /* >> + * HDM-D[B] (device-memory) regions have accelerator specific usage. >> + * Skip device-dax registration. >> + */ >> + if (cxlr->type == CXL_DECODER_DEVMEM) >> + return 0; >> + > This decision is now made twice in cxl_region_probe(). This one above, > and another one later in the function as added by Dan's incremental: > cxl/region: Introduce cxl_memdev_attach_region > > If the intent is only to avoid dax registration, then the later one > is placed better. If the intent is different, then the commit message > and comment need updating to explain its placement. Hi Allison, Maybe I was not clear enough in the RFC. When I say there "extending Dan's approach" I did not mean to be based on Dan's patch " cxl/region: Introduce cxl_memdev_attach_region" but to take part of what it does and solve the problem I stated on my reviews. Moreover, there is a disagreement about when such region attachment should happen, so Dan's approach and mine are not compatible but exclusive. I'm waiting for Dan to comment on my reply to his last comment. Hopefully, this email exchange will help to move this ... Thank you > > >> /* >> * From this point on any path that changes the region's state away from >> * CXL_CONFIG_COMMIT is also responsible for releasing the driver. >> -- >> 2.34.1 >> >>