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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id AF7CAC71157 for ; Tue, 17 Jun 2025 19:39:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4FD356B009D; Tue, 17 Jun 2025 15:39:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4AD7F6B009E; Tue, 17 Jun 2025 15:39:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3C3266B00A1; Tue, 17 Jun 2025 15:39:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 2C1F66B009D for ; Tue, 17 Jun 2025 15:39:30 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id EC9BE5D4E3 for ; Tue, 17 Jun 2025 19:39:29 +0000 (UTC) X-FDA: 83565906858.23.ECC4CB7 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf05.hostedemail.com (Postfix) with ESMTP id 9812A100008 for ; Tue, 17 Jun 2025 19:39:27 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=i7cZYVN6; spf=pass (imf05.hostedemail.com: domain of peterx@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=peterx@redhat.com; dmarc=pass (policy=quarantine) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1750189167; h=from:from:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=XJl3ISS5vZpEM73Zu2QnVbFcIkeedrpFNBWR+QK1Ynw=; b=3vKNSgjVwujHgi/BpBpGY4J/2zc2ZGKpeoHr1z0O1gX+Yqd3niZIO52q45QgNUx2aGR5ZT 0cvxnyE9GpqB4QhbYG3x0lO6wMiL2t8J/fvcLZMTDZ4pjBk5QP35VqWMV7f4oailNH5Jib iweOp/Z6RCgCJF80YDjE18oPWaXiSJ8= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=i7cZYVN6; spf=pass (imf05.hostedemail.com: domain of peterx@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=peterx@redhat.com; dmarc=pass (policy=quarantine) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1750189167; a=rsa-sha256; cv=none; b=Xip8tY8XRVnS+7lgnViucA6h4u7+IKykNFy0tjVar4oBI6pHrqqjzBgxxXiUxKXpTkr8Kb 6vUW8s3SRcADZDHOMmOZLu8LUlqVgO15MjpKvvGqx2B376S0n22xyXYuUs71lyUUK7Yyqk QK+VE8/L4k4LH+Mj3pVAuBph4Enz0Fk= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1750189167; 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: in-reply-to:in-reply-to:references:references; bh=XJl3ISS5vZpEM73Zu2QnVbFcIkeedrpFNBWR+QK1Ynw=; b=i7cZYVN6MSJFAjq37Y8sZkqitrheGKWNFzOtojrFec5DU05wrDatk1bwAomCMM1QBi/Jw9 H5JN7Wjevi9EedzE0i8RJvHaGSFFptcjpOihKi2jSx3HFZmB8YffD21j0Ij7QNeZaIbcVT h8LVRNKxwS7rnNBNx7UWXUvLnI6NfN8= Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-639-7RwDM6rEOgWmy7tbgaT29Q-1; Tue, 17 Jun 2025 15:39:25 -0400 X-MC-Unique: 7RwDM6rEOgWmy7tbgaT29Q-1 X-Mimecast-MFC-AGG-ID: 7RwDM6rEOgWmy7tbgaT29Q_1750189165 Received: by mail-pf1-f198.google.com with SMTP id d2e1a72fcca58-748764d84feso8336566b3a.2 for ; Tue, 17 Jun 2025 12:39:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1750189165; x=1750793965; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=XJl3ISS5vZpEM73Zu2QnVbFcIkeedrpFNBWR+QK1Ynw=; b=C5XO0AMIBGQiDVOg8B2+q6FR7CFkDghzzX4gUyz401qvkRLgNbmHFFsDWK5MMnxKjb Ry6FBvKze+5zgLhBOmvWex7H5/TJYwDKrGwRm7auEGlrbcPlC8hM70at23G1em9cCrgN vlOjo9F/O8WqZljXP94gQTkoGgNEJTt1pUtjazmnkThdsd5/8m479ehg/ud44AmiEqFG Y8IWASRCQYSQiaRp6nXGjcFnjFBkycihObzDkNC9C2Ma7sElz6Jtsh0WUU6qtj4jvjZJ 4RsyUcinLGmWwMzGDhQpEu0B85JuKGFODVf9X1Av28RD86x17hTl56FQkKps4NTRgLQx C7Kg== X-Forwarded-Encrypted: i=1; AJvYcCVXnRL7jy7ER9z70gWQDdtLDT3Ya+GPytEyPuIWApQzJLJlWWWOpHwa51F2s8/3AJXaaYuggsiVVA==@kvack.org X-Gm-Message-State: AOJu0YyR/mlqNVHpim5ylYPZf9RvKUHE+/mxv96CfRLfHQpDZ0iWeusp lWx6dUpEqvhQRMetsZEqDC2af/ljlhnUKiMpoCBYqrXYd/z72qbjtenB8EE9WszK7Df3IdOHbCq Srx4ImqSlPKqgPEXSGcs4oWGfErRx715diUd4irhIwGKAQpBK5Eec X-Gm-Gg: ASbGncututeD1RbHYKnhCL1d0xP0NMQTSXxQVJZ8z9+xWLicT0oby67/uqVH7QLIIad 2+e9XWcHFOP4Kakmq4MJ7k38PzfCmblniin1/ePGD2NVfyBg4iSdGuhFCDUkQFG1OOxSTxOmMVd ByJkaHYVPjZ7b9KDNZ5Bi/ukmYJXiO24UgIKziYdD8Qk+5gn2LWWEdYn3B4y6Mu8mTATSnFDX4A XZ6iHEXC8XWirvGG7w0/bYr0ap2XgxfvWXyqJZogl0OgS6Ifn+vPdfBo/Nevmu7MBI/bXQPON2M mCSnNNt5XVk/oQ== X-Received: by 2002:a05:6a00:3a19:b0:746:2ae9:fc3d with SMTP id d2e1a72fcca58-7489cffb6bbmr18361940b3a.23.1750189164738; Tue, 17 Jun 2025 12:39:24 -0700 (PDT) X-Google-Smtp-Source: AGHT+IE0d0QqjyrjopZorTKaCRFU/Z21FT70P9cxE4DFi+E6/jbvdkezfloKB99Q5wHRPPT6YtfIBg== X-Received: by 2002:a05:6a00:3a19:b0:746:2ae9:fc3d with SMTP id d2e1a72fcca58-7489cffb6bbmr18361911b3a.23.1750189164376; Tue, 17 Jun 2025 12:39:24 -0700 (PDT) Received: from x1.local ([85.131.185.92]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-748d8093c63sm1700538b3a.57.2025.06.17.12.39.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Jun 2025 12:39:23 -0700 (PDT) Date: Tue, 17 Jun 2025 15:39:19 -0400 From: Peter Xu To: Jason Gunthorpe Cc: kernel test robot , linux-kernel@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, oe-kbuild-all@lists.linux.dev, Andrew Morton , Alex Williamson , Zi Yan , Alex Mastro , David Hildenbrand , Nico Pache Subject: Re: [PATCH 4/5] vfio: Introduce vfio_device_ops.get_unmapped_area hook Message-ID: References: <20250613134111.469884-5-peterx@redhat.com> <202506142215.koMEU2rT-lkp@intel.com> <20250617154157.GY1174925@nvidia.com> MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: -xzkQeOWUPYxNb1jXMWSvat56fRw5qsZdrPGkuIsW38_1750189165 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline X-Rspamd-Server: rspam11 X-Rspam-User: X-Rspamd-Queue-Id: 9812A100008 X-Stat-Signature: 1q8q9mqiptt4been89gu19ozgpcmb84k X-HE-Tag: 1750189167-431315 X-HE-Meta: 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 Z8oghQ3k qdTBpm3uVjb4pCCmaJ9CpUN5v4DUPB+99FiD/CRu8iO0h38xuI75vzHCD53Cg0aTC77y5mEGDxftF00RAwGgrZKZsnXe/MBaJWc/T6tkXMenUkHtexzlmiR3Umi4c+SRlQS07FJ9T5WMx3xFCBLEVUd1XXZsLHdrSradOhx9u7akzpGxZnMc2TbBds6Ng+4XdM0b2d7P8VOllRDz1BefuwY8OuKvpkMn3A5siXCdZxo7EkDUGGxdT8ZxMjY5TD0wRWNCOI+QzU3nlX7gE7WN6Xl2O0LnW2BxjHbgASkAfZiNqkX08MPvqAUul+uyssZ5HtJVDQr+sIxX4PlbWocxBgn6emh02jLMVhFcKQYScXbNqpIQ4vJmpHpnoN/6c/ZC0rjxB5WOCtGF0Xd0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jun 17, 2025 at 12:47:35PM -0400, Peter Xu wrote: > On Tue, Jun 17, 2025 at 12:41:57PM -0300, Jason Gunthorpe wrote: > > On Tue, Jun 17, 2025 at 11:39:07AM -0400, Peter Xu wrote: > > > > > > +#ifdef CONFIG_ARCH_SUPPORTS_HUGE_PFNMAP > > > static unsigned long vfio_device_get_unmapped_area(struct file *file, > > > unsigned long addr, > > > unsigned long len, > > > @@ -1370,6 +1371,7 @@ static unsigned long vfio_device_get_unmapped_area(struct file *file, > > > return device->ops->get_unmapped_area(device, file, addr, len, > > > pgoff, flags); > > > } > > > +#endif > > > > > > const struct file_operations vfio_device_fops = { > > > .owner = THIS_MODULE, > > > @@ -1380,7 +1382,9 @@ const struct file_operations vfio_device_fops = { > > > .unlocked_ioctl = vfio_device_fops_unl_ioctl, > > > .compat_ioctl = compat_ptr_ioctl, > > > .mmap = vfio_device_fops_mmap, > > > +#ifdef CONFIG_ARCH_SUPPORTS_HUGE_PFNMAP > > > .get_unmapped_area = vfio_device_get_unmapped_area, > > > +#endif > > > }; > > > > IMHO this also seems like something the core code should be dealing > > with and not putting weird ifdefs in drivers. > > It may depend on whether we want to still do the fallbacks to > mm_get_unmapped_area(). I get your point in the other email but not yet > get a chance to reply. I'll try that out to see how it looks and reply > there. I just noticed this is unfortunate and special; I yet don't see a way to avoid the fallback here. Note that this is the vfio_device's fallback, even if the new helper (whatever we name it..) could do fallback internally, vfio_device still would need to be accessible to mm_get_unmapped_area() to make this config build pass. So I think I'll need my fixup here.. -- Peter Xu