2001-04-17 11:24:20

by Russell Coker

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Subject: Mylex DAC vs RAM disk in 2.4.2 devfs

I have just upgraded a machine with a Mylex DAC hardware RAID controller to
kernel 2.4.2 with devfs.

It seems that /dev/rd is used by both the RAM disk in the kernel and the
Mylex controller!

This is wrong of course, there are two problems, one is the situation of what
happens if you need both Mylex RAID and a RAM disk. The other is the problem
that Mylex devices get treated as ram disks by devfsd which cause an upgrade
to break (the compatibility sym-links are not created correctly).
I believe that the RAM disk should be changed as /dev/rd has been used by
Mylex controllers for a long time. I am willing to submit patches to the
kernel and to devfsd if this suggestion is accepted and someone can suggest a
good directory name for ram-disks (I don't want to have the same problem
again).

--
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2001-04-17 12:31:05

by Andreas Ferber

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Subject: Re: Mylex DAC vs RAM disk in 2.4.2 devfs

Hi,

On Tue, Apr 17, 2001 at 01:22:01PM +0200, Russell Coker wrote:

> Mylex controllers for a long time. I am willing to submit patches to the
> kernel and to devfsd if this suggestion is accepted and someone can suggest a
> good directory name for ram-disks (I don't want to have the same problem
> again).

What about simply "ramdisk"? ;-)

Andreas
--
"How do you pronounce SunOS?" "Just like you hear it, with a big SOS"
-- dedicated to Roland Kaltefleiter

2001-04-17 16:24:22

by H. Peter Anvin

[permalink] [raw]
Subject: Re: Mylex DAC vs RAM disk in 2.4.2 devfs

Followup to: <[email protected]>
By author: Andreas Ferber <[email protected]>
In newsgroup: linux.dev.kernel
>
> Hi,
>
> On Tue, Apr 17, 2001 at 01:22:01PM +0200, Russell Coker wrote:
>
> > Mylex controllers for a long time. I am willing to submit patches to the
> > kernel and to devfsd if this suggestion is accepted and someone can suggest a
> > good directory name for ram-disks (I don't want to have the same problem
> > again).
>
> What about simply "ramdisk"? ;-)
>

The standard name is /dev/ramX. If you want it directorized I suggest
/dev/ram/X.

-hpa
--
<[email protected]> at work, <[email protected]> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt

2001-04-18 07:18:03

by Richard Gooch

[permalink] [raw]
Subject: Re: Mylex DAC vs RAM disk in 2.4.2 devfs

Russell Coker writes:
> I have just upgraded a machine with a Mylex DAC hardware RAID controller to
> kernel 2.4.2 with devfs.
>
> It seems that /dev/rd is used by both the RAM disk in the kernel and the
> Mylex controller!
>
> This is wrong of course, there are two problems, one is the situation of what
> happens if you need both Mylex RAID and a RAM disk. The other is the problem
> that Mylex devices get treated as ram disks by devfsd which cause an upgrade
> to break (the compatibility sym-links are not created correctly).
> I believe that the RAM disk should be changed as /dev/rd has been used by
> Mylex controllers for a long time. I am willing to submit patches to the
> kernel and to devfsd if this suggestion is accepted and someone can suggest a
> good directory name for ram-disks (I don't want to have the same problem
> again).

Leonard and I are discussing the issue. We started at the kernel
summit, but didn't have time to continue. I've sent him an email.

Regards,

Richard....
Permanent: [email protected]
Current: [email protected]