Re: musl qemu-user-static not static

[ejolson2005 <ejolson2005@users.noreply.github.com>]

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New comment by ejolson2005 on void-packages repository

https://github.com/void-linux/void-packages/issues/23418#issuecomment-655303483

Comment:
I have the Raspberry Pi OS unpacked in the directory iroot and binfmt-support enabled in Void Linux for user-mode QEMU.  Then I perform the following:
```
# mount --rbind /sys iroot/sys
# mount --make-rslave iroot/sys
# mount --rbind /dev iroot/dev
# mount --make-rslave iroot/dev
# mount --rbind /dev/pts iroot/dev/pts
# mount --make-rslave iroot/dev/pts
# mount --rbind /proc iroot/proc
# mount --make-rslave iroot/proc
# cp /usr/bin/qemu-arm-static iroot/usr/bin
# cp /usr/bin/qemu-aarch64-static iroot/usr/bin
# chroot iroot
root@silver:/# ldd /bin/bash
    libtinfo.so.6 => /lib/aarch64-linux-gnu/libtinfo.so.6 (0x000000550198a000)
    libdl.so.2 => /lib/aarch64-linux-gnu/libdl.so.2 (0x00000055019ca000)
    libc.so.6 => /lib/aarch64-linux-gnu/libc.so.6 (0x00000055019de000)
    /lib/ld-linux-aarch64.so.1 (0x0000005500000000)
root@silver:/# exit
exit
# umount -R iroot/dev/pts
# umount -R iroot/sys
# umount -R iroot/dev
# umount -R iroot/proc
```
Everything seems to work fine when iroot contains the 32-bit version of Raspberry Pi OS; however, if I do the same with the 64-bit version of Raspberry Pi OS, then there is no networking in the chroot environment.  The error is something like
```
root@silver:/# ifconfig
: error fetching interface information: Device not found
root@silver:/# ip link
netlink receive error Message too long (90)
Dump terminated
```
I have no idea whether this is an issue with the x86 Void host or the 64-bit AARCH64 image.  At any rate, it would appear QEMU user-mode is working in musl even though file reports the binaries as being dynamically linked.  As I'm not up to speed on the different binary formats available with Linux, I don't know why PIE are flagged as dynamically linked.  In my opinion, this is likely to cause ongoing confusion, but this thread seems not the place to resolve that problem.

Thanks everyone for the help.  Also, if there is time, I would greatly appreciate if someone could comment on whether the bind mounts I have included above are sufficient for a properly functioning chroot environment.  In particular, have I left out something obvious that is preventing the network devices from being detected in the AARCH64 chroot?  I'm very impressed with the help so far.  Again thanks!