From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 C92342033E; Thu, 20 Jun 2024 04:11:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718856709; cv=none; b=KpnzhuQeqnvt6odBYMOImRdV38n8G+5/HPwq3EwH6r2DGyETd6qoy5NyD6skzwbiAxBKJG/4bAFsbmjZCndl2FoOTlgf6zN7uROuJytiTklQnHTRoJpMHsKWQ53th3Gfrrf1H3bcekOnLqmjig0hveCW4hNGXUKM2LQtQG6gAUo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718856709; c=relaxed/simple; bh=szJbLbfPOhwn79/2zzEjC3tpHjddQcvHJWqVSq3ENWk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=V8eClQrKejpHVUUvJN9PcophybdoBxPueA4zMULcgltfiul5Oecs1NlZ3oLEe4VhNR/rTCHPCPKfH8SfbXOgmZaBzQMVO59j58zq28NtEHBRauYM/Lboo31RKkjeG0O6g5mwpJvniQp6mciMcdfThzCFZkAgF3WKLnorKIuCReU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=H3ue6Jzl; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="H3ue6Jzl" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=TrAuEcdbN66byLYBuONA5EHUWkXbGFGEpsYr69PtaPc=; b=H3ue6Jzleheo2WqyMSlb9v3N3C 3FAJDV2HUnzNVS57QJJ+B5A5JySfcoucabLcrzK8bsTCvqvXnEAJ6Xhp5ugZzhwOtFjysW9Z3YBPT 6NPuIIcZYj0ucO4W6Vc+VnGfbNoJd5Oef9t4Bi52ptgWz3wgRxseg5muuYnycFtp8785nrhvhqHI6 1HgmrOEkdDMmOVsq8rDHZTSwclNJM/UPLQRPWslgR/DqMqQX6ifKplu9WiK/EphC/VwFXj4NLm5Yx IKDT4dP102TYC+4J/+IzAnADFxIVUVwPlKCDGpq/6WNmYpJL9Guft30azmsJnKY9fepm1USKrK+s0 Q20yf3TQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1sK99E-00000003Xoi-0s0H; Thu, 20 Jun 2024 04:11:44 +0000 Date: Wed, 19 Jun 2024 21:11:44 -0700 From: Christoph Hellwig To: Jason Gunthorpe Cc: Fuad Tabba , David Hildenbrand , John Hubbard , Elliot Berman , Andrew Morton , Shuah Khan , Matthew Wilcox , maz@kernel.org, kvm@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, pbonzini@redhat.com Subject: Re: [PATCH RFC 0/5] mm/gup: Introduce exclusive GUP pinning Message-ID: References: <20240618-exclusive-gup-v1-0-30472a19c5d1@quicinc.com> <7fb8cc2c-916a-43e1-9edf-23ed35e42f51@nvidia.com> <14bd145a-039f-4fb9-8598-384d6a051737@redhat.com> <20240619115135.GE2494510@nvidia.com> Precedence: bulk X-Mailing-List: linux-arm-msm@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: <20240619115135.GE2494510@nvidia.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Jun 19, 2024 at 08:51:35AM -0300, Jason Gunthorpe wrote: > If you can't agree with the guest_memfd people on how to get there > then maybe you need a guest_memfd2 for this slightly different special > stuff instead of intruding on the core mm so much. (though that would > be sad) Or we're just not going to support it at all. It's not like supporting this weird usage model is a must-have for Linux to start with.