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 2189D274B3B; Wed, 23 Jul 2025 08:44:17 +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=1753260258; cv=none; b=nHsrrxYX1qdPfya+ffVzUY0Q/EXCW9qAtwzys3pZ+HKzcD7TzY5DlRviR23wnmleWLGWzPcVryh/zhMPWpiakI/AlwHFpAaCoRGQ2Zv1kbKFx6h2qkwXpoigCqDuz9WdFtdexVJ4qoytWYQZYH7K3pbhyL1yQuZwsvAKs4KD32k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753260258; c=relaxed/simple; bh=Cj91CGuGavrB/ilqOlKndjatFWOMgTxiTvWRwwSAyXM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=V6laDy29CB3aQbt9MmSBiNlWYm2XxzXrdpezDFmWJXO4ilJ+4XMrnu66vJCwYa9El/QIcs0kFbkcnJh+VGfOw58qdzGMDJ2Fd38zivkZu4kwZg+N08X1faAJ8OdAod09399+ero5xp3/yGRQjZ7pNAesI/hMObv37ei+5O3BAo4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M/jQIqzd; 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="M/jQIqzd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 077C7C4CEF4; Wed, 23 Jul 2025 08:44:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753260257; bh=Cj91CGuGavrB/ilqOlKndjatFWOMgTxiTvWRwwSAyXM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=M/jQIqzdz82x0nWSTcq4f0buV83Pk0LJSgQODn5pjrmjpwv5oy9a1d8mvYOCYdVOH bdXSPn4PgwRtO9dST3nKHT5TYXR4D0lbuq0VYMy2LK2WQ8tGkqd62MiFZw3E5YA1+V APES5GMOW46WRZWXbPOt0PFGaEfxcmpX5ZU7O9INHYCZGqFw/ylFGGERRmyWD2Q5u+ C0riJKs1eAlwPzfqs69FDmjTezmgWk9NwcQbHqxK4y8D01b28cCc7w3FT3bMoQXkso mDdwnRJk7eIzRHR57iMNUzD9DuAxsqerjLb5vvC3jhbdTL1pfEkFX8w1K57J9Sc/r3 j+tg72bbOJh1Q== Date: Wed, 23 Jul 2025 11:44:13 +0300 From: Leon Romanovsky To: Jason Gunthorpe Cc: Yonatan Maman , =?iso-8859-1?B?Suly9G1l?= Glisse , Andrew Morton , Lyude Paul , Danilo Krummrich , David Airlie , Simona Vetter , Alistair Popple , Ben Skeggs , Michael Guralnik , Or Har-Toov , Daisuke Matsuda , Shay Drory , linux-mm@kvack.org, linux-rdma@vger.kernel.org, dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/5] *** GPU Direct RDMA (P2P DMA) for Device Private Pages *** Message-ID: <20250723084413.GO402218@unreal> References: <20250718115112.3881129-1-ymaman@nvidia.com> <20250720103003.GH402218@unreal> <35ff6080-9cb8-43cf-b77a-9ef3afd2ae59@nvidia.com> <20250721064904.GK402218@unreal> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jul 23, 2025 at 01:03:47AM -0300, Jason Gunthorpe wrote: > On Mon, Jul 21, 2025 at 09:49:04AM +0300, Leon Romanovsky wrote: > > > In fact, hmm_range_fault doesn't have information about the destination > > > device that will perform the DMA mapping. > > > > So probably you need to teach HMM to perform page_faults on specific device. > > That isn't how the HMM side is supposed to work, this API is just > giving the one and only P2P page that is backing the device private. I know, but somehow you need to say: "please give me p2p pages for specific device and not random device in the system as it is now". This is what is missing from my PoV. Thanks