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 X-Spam-Level: X-Spam-Status: No, score=-12.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB517C433B4 for ; Mon, 17 May 2021 22:05:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91C0F61166 for ; Mon, 17 May 2021 22:05:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238213AbhEQWGQ (ORCPT ); Mon, 17 May 2021 18:06:16 -0400 Received: from gimli.rothwell.id.au ([103.230.158.156]:59043 "EHLO gimli.rothwell.id.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235143AbhEQWGO (ORCPT ); Mon, 17 May 2021 18:06:14 -0400 Received: from authenticated.rothwell.id.au (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.rothwell.id.au (Postfix) with ESMTPSA id 4FkY8L0S1vzyQJ; Tue, 18 May 2021 08:04:49 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=rothwell.id.au; s=201702; t=1621289095; bh=3zQXipN+5rOCvuSWYiWEGaHiIwQkUt3DbG1nZj86/GA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=HR05GDKDWir9rgKkNqrsP3gB9XDLsEcqyIvUHVkqm/81SVLRh95UaKWlAzs1Sv6FS EdvTZ8ePSqaUgMoCtJCdWuOxNjbJmVGI/qoV1ZtToTpr7LyBtOkCSmwQWJNLB1FxbS xNnTzmmQMrtA4DtMnGhNGAiHbbBLeNAGOEU/cyfS97qKdCVfXGRHy5wqGsG6rUZXQw YK79e1iKJTXf5ReYrjvWE3sClmplCce00k8aYXkPKYKAgDp44J2EI76SN2V7aApLp+ J7h8ZC+kEmV6Ye048s2mUco9cIxyfmgfOdrsuXWrSuhKR1oSXX9qdoN0b7AYBFGXb8 giw94aHB87aDg== Date: Tue, 18 May 2021 08:04:42 +1000 From: Stephen Rothwell To: Daniel Vetter Cc: Christoph Hellwig , Stephen Rothwell , Linus Torvalds , Tomasz Figa , Marek Szyprowski , Mauro Carvalho Chehab , DRI Development , LKML , Linux-MM , Linux ARM , Linux Media Mailing List , linux-samsung-soc Subject: Re: [PULL] topic/iomem-mmap-vs-gup Message-ID: <20210518080442.28080686@elm.ozlabs.ibm.com> In-Reply-To: References: X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/aggeSpPGRwf/ibiafiFMPrw"; protocol="application/pgp-signature"; micalg=pgp-sha256 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/aggeSpPGRwf/ibiafiFMPrw Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Daniel, On Mon, 17 May 2021 17:29:35 +0200 Daniel Vetter w= rote: > > On Mon, May 10, 2021 at 9:30 AM Christoph Hellwig wro= te: > > > > On Mon, May 10, 2021 at 09:16:58AM +0200, Daniel Vetter wrote: =20 > > > > End result: not pulling it, unless somebody can explain to me in sm= all > > > > words why I'm wrong and have the mental capacity of a damaged roden= t. =20 > > > > > > No rodents I think, just more backstory of how this all fits. tldr; > > > pin_user_pages is the only safe use of this vb2 userptr thing. =20 > > > > Yes, which is why I advocate for just ripping the follow_pfn path > > out entirely. It could have been used for crazy ad dangerous peer to > > peer transfers outside of any infrastructure making it safe, or for > > pre-CMA kernel memory carveouts for lage contiguous memory allocations > > (which are pretty broken by design as well). So IMHO the only sensible > > thing is to remove this cruft entirely, and if it breaks a currently > > working setup (which I think is unlikely) we'll have to make sure it > > can work the proper way. =20 >=20 > Since I'm not getting any cozy consenus vibes here on any option I > think I'll just drop this. >=20 > Stephen, can you pls drop >=20 > git://anongit.freedesktop.org/drm/drm topic/iomem-mmap-vs-gup >=20 > from linux-next? It's not going anywhere. I'll also go ahead and > delete the branch, to make sure you catch this update :-) I have dropped this now. Thanks for letting me know. --=20 Cheers, Stephen Rothwell --Sig_/aggeSpPGRwf/ibiafiFMPrw Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAmCi6HoACgkQAVBC80lX 0GyNzAf+PsJKuLMSyGdrI9Eb1SKOtnkBb4Phs9Z2XAd9Ch2v94oPoiB9Q+2fMR3X YDjZPndyD/LzF1qIRGWDZLhcf8FBU80ZXRNxTfw+yjoH9wcj+cQl5Nlw/qTdINnZ FI/aXekpdIFmzXYWl3+6h2RCq/C/+/fl3hIDqRyNgSRWIx+oqk97eSB4WEnynGLB ng3poVuFFymwD/y9fDhCyEKfwjEDZqu+fiaYS0Jvl+e9nx19iScrMtm9jVmS7F4Y yHItNAj7wnhP+UqJ4Xs2LoQv+AfX0amYwjVqen/f4mEY5cVwBgMmTiVi/7I9nQVe 5nXKiM/GXzrpZDuYnZelmd+uAsn+Gw== =3/Jz -----END PGP SIGNATURE----- --Sig_/aggeSpPGRwf/ibiafiFMPrw--