From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F34D73EDABE; Wed, 21 Jan 2026 15:46:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769010386; cv=none; b=NWgsexj5dyZXrtSo7eYIfQN9IG6GMMbRPj8ymAuiExXSPWImbrSUEGUAhfPZJmsi/XuHiCR5CNpjXneevE6/z1677cuKi02g5koLtcDYamDdZSd7SOVjAm4T2xIqU/EFxZx4LPwThIPIdManrFKvWCYfNSwgKAFn0S6HKhyPd2w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769010386; c=relaxed/simple; bh=wsp0Ee/Wyi7vSUVwVM1dt7Rh8gLnheehWV+BoZfOvsU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=SyWr7/l1IZXmovXzKQYUroo1D0jFTB9VcAQzwtEQFmgM+qKXbhZB7w9jX8PRNrl6ITubqUBgp987SR+IodRgr8pQS/DkqNJKm99isiCh6bHvMu+1y633XEI0NlaMmVM2l6XXA6yJMttwYsDcu/0ebNrXUQT8gdvWVyZaUQPlVfM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t97wEG8R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="t97wEG8R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C79C7C4CEF1; Wed, 21 Jan 2026 15:46:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769010385; bh=wsp0Ee/Wyi7vSUVwVM1dt7Rh8gLnheehWV+BoZfOvsU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=t97wEG8R3Vclg+HjbADh6Re31LoTY+IEQ//+/mnlWg1SY0DWWznX+wkzufS/8RTPw cFRK4kAf7NSHmPyBgCi82jqY7mcIsr1SPIUA+DfGH+0sVbcGIIjaD3E9NvDWdaGQVx LdTOIbm0sfpJbWGFzlKIoFrPX2a1YPoLdupT/uZEE8P5zTY/Y9osGFW/VyLT82WWgJ TZMQRbM9NUBS2Upq18HxU+6bzyq7clPDWPDeMzkHTDGuxQmBCpWoxQ0JRBZ6ihl7MC pISuKsiX5PxQGXQHWql6x3YzR56jEtvSfhu2oH2477i9lN+U+568UYrW9OFuumSVq0 ES+FsrOJCjoVw== Date: Wed, 21 Jan 2026 17:46:21 +0200 From: Leon Romanovsky To: Jason Gunthorpe , Alex Williamson Cc: Sumit Semwal , Christian =?iso-8859-1?Q?K=F6nig?= , Alex Deucher , David Airlie , Simona Vetter , Gerd Hoffmann , Dmitry Osipenko , Gurchetan Singh , Chia-I Wu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Lucas De Marchi , Thomas =?iso-8859-1?Q?Hellstr=F6m?= , Rodrigo Vivi , Kevin Tian , Joerg Roedel , Will Deacon , Robin Murphy , Felix Kuehling , Ankit Agrawal , Vivek Kasireddy , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, virtualization@lists.linux.dev, intel-xe@lists.freedesktop.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, kvm@vger.kernel.org Subject: Re: [PATCH v4 8/8] vfio: Validate dma-buf revocation semantics Message-ID: <20260121154621.GH13201@unreal> References: <20260121-dmabuf-revoke-v4-0-d311cbc8633d@nvidia.com> <20260121-dmabuf-revoke-v4-8-d311cbc8633d@nvidia.com> <20260121134712.GZ961572@ziepe.ca> <20260121144701.GF13201@unreal> <20260121154137.GD961572@ziepe.ca> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260121154137.GD961572@ziepe.ca> On Wed, Jan 21, 2026 at 11:41:37AM -0400, Jason Gunthorpe wrote: > On Wed, Jan 21, 2026 at 04:47:01PM +0200, Leon Romanovsky wrote: > > > We need to push an urgent -rc fix to implement a pin function here > > > that always fails. That was missed and it means things like rdma can > > > import vfio when the intention was to block that. It would be bad for > > > that uAPI mistake to reach a released kernel. > > > > I don't see any urgency here. In the current kernel, the RDMA importer > > prints a warning to indicate it was attached to the wrong exporter. > > VFIO also invokes dma_buf_move_notify(). > > The design of vfio was always that it must not work with RDMA because > we cannot tolerate the errors that happen due to ignoring the > move_notify. > > The entire purpose of this series could be stated as continuing to > block RDMA while opening up other pining users. > > So it must be addressed urgently before someone builds an application > relying on this connection. Done, https://lore.kernel.org/all/20260121-vfio-add-pin-v1-1-4e04916b17f1@nvidia.com/T/#u Thanks > > Jason