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On Thu, 29 Mar 2012 22:55:42 +0200, Alan McKinnon wrote: |
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> I don't think I agree with Neil in that this is a udev design flaw (as |
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> any "fix" will be worse than the "flaw"). Instead it looks to me like |
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> a classic case of |
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> |
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> "You are free to do anything you want but if you break it you keep the |
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> pieces. If you do something stupid, it's not my problem and you're on |
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> your own." |
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> |
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> I see nothing wrong with udev applying some reasonable constraints such |
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> as clearly documenting at what point in the boot process udev is in a |
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> position to arbitrarily run anything. Earlier than that point, |
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> "anything" does not actually apply. |
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The reason I think it is a flaw is that udev is capable of doing some |
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very clever stuff with nothing more than a simple device rule, but such |
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clever stuff has no place in early boot. On the other hand, it also does |
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basic stuff, like creating device nodes, that certainly does belong in |
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early boot. The problem is that udev provides no way to distinguish |
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between the early boot essentials and the clever stuff. |
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Only a small subset of its work should be done when it is first started, |
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possibly by tagging those rules, or simply postponing any rules with a |
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RUN command. Or maybe a separate command (or invocation of the same |
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command) that just creates device nodes, and any specified symlinks, much |
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like mdev does, then kick in the full version later. |
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However, as I type this, I can think of all sorts of arguments about what |
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should be run early and what not. I'm beginning to understand why the |
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devs decided "if you want all this clever stuff, you'll just have to |
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make /usr available". |
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-- |
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Neil Bothwick |
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Windows Error:01F Reserved for future mistakes. |
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