Re: Unable to build cdrom: failed to setup loop device

[Michael Tremer <michael.tremer@ipfire.org>]

[-- Attachment #1: Type: text/plain, Size: 2938 bytes --]

Hello Robin,

> On 4 Sep 2024, at 20:53, Robin Roevens <robin.roevens(a)disroot.org> wrote:
> 
> Hi all
> 
> While trying to build ipfire, which always has worked quite effortless,
> it now fails while building cdrom:
> 
> ---
>    # Create the EFI Eltorito image
>    dd if=/dev/zero of=/tmp/cdrom/boot/isolinux/efiboot.img bs=1k
> count=2880
>    2880+0 records in
>    2880+0 records out
>    2949120 bytes (2.9 MB, 2.8 MiB) copied, 0.00453183 s, 651 MB/s
>    mkdosfs -F 12 -n "IPFIRE_EFI" /tmp/cdrom/boot/isolinux/efiboot.img
>    mkfs.fat 4.2 (2021-01-31)
>    # Mount the EFI image
>    mkdir -pv /tmp/efiboot.img
>    mkdir: created directory '/tmp/efiboot.img'
>    mount -o loop /tmp/cdrom/boot/isolinux/efiboot.img /tmp/efiboot.img
>    mount: /tmp/efiboot.img: failed to setup loop device for
> /tmp/cdrom/boot/isolinux/efiboot.img.
>    make: *** [cdrom:184: /usr/src/log/cdrom] Error 32
>    make: Leaving directory '/usr/src/lfs'
> 
> ERROR: Building cdrom                                                 
> [ FAIL ]
>    Check /home/robin/src/ipfire-sandbox/ipfire-
> 2.x/log_x86_64/_build.ipfire.log for errors if applicable             
> [ FAIL ]
> ---

What is the output of “losetup” after this fails?

> The logfile has no extra or new information.
> 
> When I manually try those steps, as root (as make.sh is also ran as
> root (using sudo)), they work correctly, and I'm able to successfully
> mount the image.

Does this also work in shell?

> 
> ---
> $ sudo dd if=/dev/zero of=./efiboot.img bs=1k count=2880 
> 2880+0 records gelezen
> 2880+0 records geschreven
> 2949120 bytes (2,9 MB, 2,8 MiB) gekopieerd, 0,0130511 s, 226 MB/s
> $ sudo ./build/sbin/mkdosfs -F 12 -n "IPFIRE_EFI" ./efiboot.img
> mkfs.fat 4.2 (2021-01-31)
> $ sudo mkdir ./efi
> $ sudo mount -o loop ./efiboot.img ./efi
> $ df -h ./efi                                                         
> Bestandssysteem Grootte Gebruikt Besch Geb% Aangekoppeld op
> /dev/loop15        2,8M        0  2,8M   0% /home/robin/src/ipfire-
> sandbox/ipfire-2.x/efi
> ---
> 
> So I'm unsure as of why the build fails setting up the loop device.
> I did a ./make.sh clean, but that didn't solve it.
> 
> If I try to mount the loop device as unprivileged user, I get the exact
> same error. But the build process is ran as root, so that should also
> not be the problem?

It creates new namespaces in which root is less privileged than in the first namespace.

> Has anyone an idea what could be wrong here? or give me some guidelines
> on how to debug this ? 
> I've read there where changes to the inner workings of the build
> system, could those be the cause ? I assume not as then I would have
> seen others complain about it here?

Apart from that, as Adolf requested, please provide us with some more information about your kernel and distribution.

-Michael

> Robin