2005-01-02 00:16:17

by Bodo Eggert

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Subject: Re: Problems with 2.6.10

Fryderyk Mazurek wrote:

> At last I fixed my problem! I changed source to not enable "Host
> Protected Area". This means that on 2.6.10 I have 33,8GB disk, not
> 40GB, how on "true" 2.6.10. And now my BIOS detect my disk. But
> question is, what does "true" kernel do, and why influence to BIOS?
> Maybe this is kernel BUG?

I can see the reason why this happens: When you boot, your HDD will be in
a compatibility mode for broken BIOSes, but it will not enter compatibility
mode on reboot. (Is it supposed to work this way, or should the BIOS
completely reset the device?)

There may be two solutions for this problem:
- Reset the drive (hdparm -w) before rebooting (just a quick workaround)
- Remember the initial state during runtime and restore it before reboot

The first option may not work at all, I'm just guessing here.
The second option will require a feature enheancement to the IDE subsystem.

To quickly find out if option 1 is enough, you could boot a non-patched
kernel with init=/bin/sh. In the shell, enter:
# hdparm -w
# shutdown -n -r now

If it works for your problen, hdparm will probably disable propper access
to the HDD until reboot. (This could mean some other cases might be broken,
too.)


2005-01-02 01:05:21

by Andries Brouwer

[permalink] [raw]
Subject: Re: [ide] ide-disk: enable stroke by default - was Re: Problems with 2.6.10

> Fryderyk Mazurek wrote:
>
> > At last I fixed my problem! I changed source to not enable "Host
> > Protected Area". This means that on 2.6.10 I have 33,8GB disk, not
> > 40GB, how on "true" 2.6.10. And now my BIOS detect my disk. But
> > question is, what does "true" kernel do, and why influence to BIOS?
> > Maybe this is kernel BUG?

Yes, I see the changeset

<bzolnier@trik.(none)> (04/10/29 1.2341)
[ide] ide-disk: enable stroke by default
From: Jens Axboe <[email protected]>

that enables stroke by default. That is good.
What I don't see is the option not to enable it.
That is, we used to have "stroke", but we want to have "nostroke".

Andries

2005-01-02 02:45:16

by Rogério Brito

[permalink] [raw]
Subject: Re: [ide] ide-disk: enable stroke by default - was Re: Problems with 2.6.10

On Jan 02 2005, Andries Brouwer wrote:
> That is, we used to have "stroke", but we want to have "nostroke".

What exactly does "stroke" mean? The description in the help file is a bit
cryptic for a layman.

Another option where the help description could be slighly improved IMVHO
is that regarding word93, althought it has certainly improved in terms of
its original description.



Thanks in advance, Rog?rio.

--
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Rog?rio Brito - [email protected] - http://www.ime.usp.br/~rbrito
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2005-01-02 03:07:59

by Andries Brouwer

[permalink] [raw]
Subject: Re: [ide] ide-disk: enable stroke by default - was Re: Problems with 2.6.10

On Sun, Jan 02, 2005 at 12:44:51AM -0200, Rog?rio Brito wrote:
> On Jan 02 2005, Andries Brouwer wrote:
> > That is, we used to have "stroke", but we want to have "nostroke".
>
> What exactly does "stroke" mean? The description in the help file is a bit
> cryptic for a layman.

It is possible to set the size of the disk to something smaller than
its actual size, either temporarily (can be undone at will) or permanently
(valid until the next reboot). It is also possible to attach a password
to this change.

One of the reasons is that people want to have code or data at the end
of the disk (operating system, diagnostics, backup, other) that the user
cannot tamper with.

But the existence of BIOSes that cannot handle large disks gives another
use of this "setmax" operation: make the disk appear smaller at the time
the BIOS looks at it, and give it full size under Linux.

Now that I think about it - the originator of this thread had problems
rebooting with the full-size disk since his BIOS didnt like it.
Instead of using a kernel boot option "nostroke", it is possible that
he could use my utility setmax at reboot time to make the disk smaller again.
That would allow use of the full disk under Linux.

Andries