From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752484AbZH1Pbj (ORCPT ); Fri, 28 Aug 2009 11:31:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751839AbZH1Pbi (ORCPT ); Fri, 28 Aug 2009 11:31:38 -0400 Received: from an-out-0708.google.com ([209.85.132.247]:35467 "EHLO an-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752053AbZH1Pbh (ORCPT ); Fri, 28 Aug 2009 11:31:37 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type; b=JMlS3rTP+NhlCA1myToiLu4KBgwo9xuCPPiJ/Uc/pQ4e9adS7iJbDr8O+VlArTHsQW qEOv8BJC/uccigD2Lefd4iDn8Mp2lgLs1rXPV6hQuRf9cA3rF1JsNFoEu3Ri8r/ecSKv Ld3CFfkYIslxfOe9TjIGwJrfXbKLlpw8lWgZ0= Message-ID: <4A97F852.6060505@gmail.com> Date: Fri, 28 Aug 2009 11:31:30 -0400 From: Gregory Haskins User-Agent: Thunderbird 2.0.0.23 (Macintosh/20090812) MIME-Version: 1.0 To: "Michael S. Tsirkin" , akpm@linux-foundation.org CC: netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@elte.hu, linux-mm@kvack.org, hpa@zytor.com, Rusty Russell , s.hetze@linux-ag.com Subject: Re: [PATCHv5 1/3] mm: export use_mm/unuse_mm to modules References: <20090827160656.GB23722@redhat.com> In-Reply-To: <20090827160656.GB23722@redhat.com> X-Enigmail-Version: 0.96.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig1C5BA6B72C76D6CD23C7D55F" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig1C5BA6B72C76D6CD23C7D55F Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Michael S. Tsirkin wrote: > vhost net module wants to do copy to/from user from a kernel thread, > which needs use_mm (like what fs/aio has). Move that into mm/ and > export to modules. Michael, Andrew, I am just curious: Is there any technical reason why a kthread cannot have a long-term use_mm() in effect? (Assuming this makes sense for the design, of course). For the cases there we know the kthread will always service the same context (such as with venettap/vhost, it may make sense to do a use_mm() at init time and just leave it until the thread exits. Will this break anything? Kind Regards, -Greg --------------enig1C5BA6B72C76D6CD23C7D55F Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.11 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkqX+FIACgkQP5K2CMvXmqGsNACghgmvgLjfVfN25itYVCnOSH4G CIwAn1VdFGYr8TJCQTlY3E1yjibfYjMF =3B87 -----END PGP SIGNATURE----- --------------enig1C5BA6B72C76D6CD23C7D55F--