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Il 12/08/2012 14:25, Rich Freeman ha scritto: |
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> On Sun, Aug 12, 2012 at 5:43 AM, Duncan<1i5t5.duncan@×××.net> wrote: |
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>> Peter Stuge posted on Sun, 12 Aug 2012 02:12:38 +0200 as excerpted: |
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>>> What software parses the filesystem labels when you boot with openrc? |
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>>> |
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>>> (I ask because I never use labels myself.) |
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>> Short answer, mount and udev, and the kernel directly when fed that |
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>> information for root= on the kernel commandline. |
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>> ... |
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>> It'a also worth noting that the kernel's root= line can take a number of |
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>> these (I'm not sure if it can take them all), including partlabel, |
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>> according to information someone posted on the btrfs list |
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> I'm pretty sure that this particular part of your post is incorrect, |
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> but I'd be happy to be corrected. |
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> |
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> The kernel cannot interpret a root= parameter that doesn't reference a |
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> device node that it can't internally generate (with a devtmpfs/etc). |
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> I'm pretty sure that rules out just about anything but a physical |
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> device (not even /dev/by-uuid/...). |
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> |
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> I think that people get this confused because 99% of linux users have |
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> an initramfs (and about 2% of Gentoo users it seems), and most |
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> initramfs implementations DO interpret the root=parameter. If you |
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> specify an initramfs then the kernel actually ignores the |
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> root=parameter entirely, mounting the initramfs as root, and passing |
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> control to its init. The initramfs is expected to mount root (or not |
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> - you could just run the whole system off an initramfs I guess). Most |
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> initramfs implementations just parse the root= line on the kernel, |
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> although it is worth noting that genkernel's initramfs does not and |
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> uses real_root instead. |
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> |
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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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> Rich |
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> |
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Yes it's incorrect, a kernel w/out initrd is not able to mount by LABEL, |
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even with automounted /dev |
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experienced few weeks ago. |
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