Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261224AbUKEWiM (ORCPT ); Fri, 5 Nov 2004 17:38:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261229AbUKEWiM (ORCPT ); Fri, 5 Nov 2004 17:38:12 -0500 Received: from ctb-mesg2.saix.net ([196.25.240.74]:4763 "EHLO ctb-mesg2.saix.net") by vger.kernel.org with ESMTP id S261224AbUKEWhv (ORCPT ); Fri, 5 Nov 2004 17:37:51 -0500 Subject: Re: support of older compilers [u] From: "Martin Schlemmer [c]" Reply-To: Martin Schlemmer To: Grzegorz Kulewski Cc: Linus Torvalds , Chris Wedgwood , Andries Brouwer , Adam Heath , Christoph Hellwig , Timothy Miller , Linux Kernel Mailing List In-Reply-To: References: <20041103233029.GA16982@taniwha.stupidest.org> <20041105014146.GA7397@pclin040.win.tue.nl> <20041105195045.GA16766@taniwha.stupidest.org> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-aaYfq9EkTpmoBGh1dRE/" Date: Sat, 06 Nov 2004 00:37:26 +0200 Message-Id: <1099694246.4450.11.camel@nosferatu.lan> Mime-Version: 1.0 X-Mailer: Evolution 2.0.2 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3466 Lines: 101 --=-aaYfq9EkTpmoBGh1dRE/ Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Fri, 2004-11-05 at 22:59 +0100, Grzegorz Kulewski wrote: > > The kernel does do more these days than it did in '95. But 6 times more= ? I > > dunno.. >=20 > Can't we remove ramfs for a good start? Everyone should use tmpfs instead= =20 > and some stupid distributions (I will not tell their names) try to mount=20 > ramfs on /dev (udev) and that leads to very stupid panic if you will=20 > write for example: >=20 > dd if=3D/dev/evms/sda5 of=3D/dev/sda17 bs=3D1024 >=20 > instead of "of=3D/dev/evms/sda17". >=20 > Explanation (if anybody needs one): > Kernel can't create more partition devices than 15 for SCSI and SATA disk= s=20 > because of lack of minor numbers. So I am using evms to create these=20 > devices. So I should use /dev/evms/sda* for these partitions. And if I=20 > will not remember to do so then I will get oom panic very shortly because= =20 > ramfs is not limited (in contrary to tmpfs). >=20 > And this kind of stupid mistake can happen. It happened to me 3 times in = a=20 > row before I started to debug what is wrong with this kernel. >=20 > [BTW. Does somebody know how to tell the kernel that I do not want=20 > /dev/sda[0-9]* files (but I do want /dev/hda files) created =3D=3D I do n= ot=20 > want kernel partition driver to touch this particular device?] >=20 So basically /dev/sda* have major of scsi, and /dev/evms/sda* have major of evms, and you end up using the wrong nodes? This sounds more like a udev-ruleset problem (not something that will be easy to get right with a generic one I imagine), rather than anything remotely to do with ramfs. If you changed the scripts to use tmpfs rather, you would have gotten the same result. Now I do not know evms, so you are on your own there, but here is my rules for dm and a similar issue: --------- nosferatu linux-2.6-bk # cat /etc/udev/rules.d/30-sda.rules KERNEL=3D"sda[0-9]*", NAME=3D"" nosferatu linux-2.6-bk # cat /etc/udev/rules.d/40-dm.rules KERNEL=3D"dm-[0-9]*", PROGRAM=3D"/sbin/devmap_name %M %m", NAME=3D"mapper/%= c", SYMLINK=3D"%c" nosferatu linux-2.6-bk # --------- (note that they should be before all the others if you only have one rule file) So basically for the real scsi devices (you could add a BUS=3D"scsi" to make sure I guess) matching 'sda[0-9]*' no node will be created, and I get my /dev/mapper/* nodes, with a symlink in /dev/ making things easier. you could have a rule catching all evms devices, and then add the /dev/sda* symlinks, perhaps like so: -------- KERNEL=3D"evms/sda[0-9]*", SYMLINK=3D"sda%n" -------- Note that I do not know if a rule was needed to get the nodes in /dev/evms/ in the first place (due to my admitted lack of evms knowledge above), so you might have to modify an existing rule ... --=20 Martin Schlemmer --=-aaYfq9EkTpmoBGh1dRE/ Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.6 (GNU/Linux) iD8DBQBBjACmqburzKaJYLYRAt8oAKCJTxI2E5tEzyysrq9Jx8pFP6gWTgCfSOom LA7Te1AIJdATUjnYVUSLTsc= =Pa9z -----END PGP SIGNATURE----- --=-aaYfq9EkTpmoBGh1dRE/-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/