RAID superblock....

[Rogier Wolff]

Hi,

The MD code I see doing: 

488         sb_offset = calc_dev_sboffset(rdev->dev, rdev->mddev, 1);
489         rdev->sb_offset = sb_offset;
490         fsync_dev(dev);
491         set_blocksize (dev, MD_SB_BYTES);
492         bh = bread (dev, sb_offset / MD_SB_BLOCKS, MD_SB_BYTES);

where sb_offset is calculated as: 

290         if (blk_size[MAJOR(dev)])
291                 size = blk_size[MAJOR(dev)][MINOR(dev)];

Now, for aguments sake, I have a 4k disk. I'd expect the size to be 4
(1k blocks, according to the comment near the definition of blk_size). 

Thus the "bread" would effectively try to read the block at offset 4k. 

That would be past the end of my mini-disk, right?

I would have expected a "-1" in there somewhere, to get the last block
of the dev, and not the block just past the end of the drive.

Anyway on the old machine, I still cannot find the raid superblock by
hand, but the drives now mount, so the kernel must have been able to
locate them somehow......

The machine is still running 2.4.16 + IDE patches for 48 bit
addressing.

The working machine is an 850MHz PIII w/384Mb RAM, the non-working
machine is an AMD 1800+ MP w/1G RAM (with another one of those
processors sitting idle close by)...

				Roger. 

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