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On 07/22/14 15:28, Phil Tooley wrote: |
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> Hi all, |
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> |
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> I have been looking at the handbook section regarding a qemu-user chroot |
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> and have some serious concerns about part of it. Specifically, in the |
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> section for setting up the chroot it is suggested to run |
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> |
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> chroot . /bin/busybox mdev -s |
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> |
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> Since I (like most others) am currently running udev, this seems to me like |
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> a very bad idea. (And indeed this is confirmed when I try it on my dev VM, |
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> where the permissions for /dev/pts /dev/null /dev/random etc. are messed up |
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> by this) |
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> |
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> Can someone please explain the logic here, since as far as I can tell so |
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> far, simply omitting this step does no major harm. |
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> |
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> Cheers |
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> |
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> Phil Tooley |
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> |
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|
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Read the mdev primer: |
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http://git.busybox.net/busybox/tree/docs/mdev.txt |
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Basically it does a population of /dev via /sys and if it has a config |
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file, will set permissions. |
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So if you omit this step you may have a <chroot>/dev which has incorrect |
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permissions for your chroot. |
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If you are running a chroot and you `mount --bind /dev <chroot>/dev` |
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then changing the permissions in /dev may mess up your real root. |
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My recommendation is to not do a bind mount and just populate a fresh |
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<chroot>/dev. |
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|
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-- |
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Anthony G. Basile, Ph. D. |
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Chair of Information Technology |
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D'Youville College |
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Buffalo, NY 14201 |
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(716) 829-8197 |
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