[linux-lvm] Fwd: [[email protected]: LVM tools broken on PPC (and many other archs)]

This is a general LVM driver issue, and therefore something that's more appropriate for the main LVM developers to deal with, as don't have access to non-Intel hardware and I don't have the knowledge of LVM driver internals that these people have it doesn't make sense for me to try and deal with this.

I am sending this message to the LVM mailing list, hopefully someone there can resolve this issue.

---------- Forwarded Message ----------
Subject: [[email protected]: LVM tools broken on PPC (and many other archs)]
Date: Sun, 17 Dec 2000 01:39:48 +0100
From: Marco d'Itri <[email protected]>
To: [email protected]

Please add this fix to your LVM package, it's needed on most architectures.

--
ciao,
Marco
Date: Fri, 15 Dec 2000 18:07:27 +0100
From: Marco d'Itri <[email protected]>
To: [email protected]
Cc: [email protected]
Subject: LVM tools broken on PPC (and many other archs)
Message-ID: <[email protected]>
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pv_get_size() tries parsing the MBR, but that fails on PPC because of the different endianess from what the function expects.

The result is that the tools think the partition is as big as the whole disk, and everything seems to work until you put enough data in the file system and some of the non existent blocks are used (the kernel will complain and return EIO, but at least it does not explode).

From the changelog I see Andrea Arcangeli contributed a very crude workaround for the alpha platform, which has the same endianess of i386 but (I suppose) a different disk label format.
The same "fix" works for PPC too (and sparc, and so on), so I think the #ifndef __alpha__ at the beginning of lib/pv_get_size.c should really be #ifdef __i386__ until some better code is written (FYI, you can find byte swapping code within fdisk).

The fix needs to be fixed too, because other code will expect something in the buffer pointed by the second argument. I just added that at the end of the function:

        if (dummy)
                memset(dummy, 0, sizeof (struct partition));

With this fix, everything seems to work fine.

--
ciao,
Marco

-------------------------------------------------------

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I have access to a PPC box (an iMac DV running Debian), so I can test the changes eventually done to the code. I can't promise a fix myself since I'm no PPC expert, and no LVM expert either.

I'll have a look.