From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id 8B0928D003B for ; Tue, 19 Apr 2011 07:35:13 -0400 (EDT) Subject: Re: [PATCH v3 2.6.39-rc1-tip 12/26] 12: uprobes: slot allocation for uprobes From: Peter Zijlstra In-Reply-To: <20110419062654.GB10698@linux.vnet.ibm.com> References: <20110401143223.15455.19844.sendpatchset@localhost6.localdomain6> <20110401143457.15455.64839.sendpatchset@localhost6.localdomain6> <1303145171.32491.886.camel@twins> <20110419062654.GB10698@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Date: Tue, 19 Apr 2011 11:02:26 +0200 Message-ID: <1303203746.32491.913.camel@twins> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Srikar Dronamraju Cc: James Morris , Ingo Molnar , Steven Rostedt , Linux-mm , Arnaldo Carvalho de Melo , Linus Torvalds , Jonathan Corbet , Christoph Hellwig , Masami Hiramatsu , Thomas Gleixner , Ananth N Mavinakayanahalli , Oleg Nesterov , Andrew Morton , SystemTap , Jim Keniston , Roland McGrath , Andi Kleen , LKML On Tue, 2011-04-19 at 11:56 +0530, Srikar Dronamraju wrote: > > > + /* > > > + * Find the end of the top mapping and skip a page. > > > + * If there is no space for PAGE_SIZE above > > > + * that, mmap will ignore our address hint. > > > + * > > > + * We allocate a "fake" unlinked shmem file because > > > + * anonymous memory might not be granted execute > > > + * permission when the selinux security hooks have > > > + * their way. > > > + */ > >=20 > > That just annoys me, so we're working around some stupid sekurity crap, > > executable anonymous maps are perfectly fine, also what do JITs do? >=20 > Yes, we are working around selinux security hooks, but do we have a > choice.=20 Of course you have a choice, mark selinux broken and let them sort it ;-) Anyway, it looks like install_special_mapping() the thing I think you ought to use (and I'm sure I said that before) also wobbles around selinux by using security_file_mmap() even though its very clearly not a file mmap (hint: vm_file =3D=3D NULL). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org