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Chí-Thanh Christopher Nguyễn posted on Sun, 12 Aug 2012 15:43:02 +0200 as |
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excerpted: |
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|
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> Rich Freeman schrieb: |
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>> So, I could see how many linux users might think that interpreting a |
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>> complex root= parameter is a kernel function, when it is really just |
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>> the fact that they use an initramfs. |
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>> |
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>> If somebody is running with root=LABEL=foo or something like that |
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>> without an initramfs I'll happily stand corrected. |
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> |
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> If your disk is GPT partitioned, then you can use root=PARTUUID=... |
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> without initramfs. |
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> Note that PARTUUID is the partition UUID, not the filesystem UUID. |
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Thanks. |
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Note that the btrfs list discussion was in the context of gpt partlabels |
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(and that I specifically said I don't know if the kernel takes all such |
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assignments in root= or just that in the discussion), so it's quite |
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possible only partlabels and partuuids are accepted, as these are found |
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in the gpt partition table itself, which the kernel must know how to |
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parse in general, so teaching it to parse and honor these probably |
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wasn't /that/ much more work than teaching it to parse the table but |
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ignore them. |
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And the gpt handling code is new enough, it may have simply been added |
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with/for it, without touching the legacy mbr code. |
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Another variable may be bootloader. Grub2 has legacy linux16 loader |
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support, as well as 32-bit "linux" support. Between that and the fact |
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that it was designed to handle both BIOS and EFI systems, it's quite |
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possible that the legacy 16-bit linux loader protocol doesn't support |
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these features, while the 32-bit (and presumably 64-bit EFI) kernel |
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loader protocol does. I've no idea what grub-legacy used, but it |
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wouldn't surprise me if it was the legacy 16-bit loader protocol, and |
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that feeding root=PARTID= won't work for it but will with the 32-bit |
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loader grub2 defaults to. |
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I really should try it one of these days and know from personal |
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experience, but in this case, it really /is/ easier to just talk than to |
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do, since trying it requires rebooting, so I can't simply try it in |
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another window while I keep this post open, waiting on the result... |
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-- |
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Duncan - List replies preferred. No HTML msgs. |
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"Every nonfree program has a lord, a master -- |
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and if you use the program, he is your master." Richard Stallman |
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