Re: [reiser4 SFRN 5.1.3] kernel [5.10.x] read not supported for file /test-exec \(pid: 10094 comm: debootstrap\)

[Edward Shishkin]

On 12/23/2020 05:01 PM, Metztli Information Technology wrote:
> Niltze [Здравствуйте : Hello], Ed-
>
> I built Linux kernel 5.10.1-1 within the 'Debian way' -- as usual -- to generate a kernel component for my Debian-Installer (d-i).
> The patch I applied is reiser4-for-5.10-rc3.patch.gz from v5-unstable.
>
> Once I built the proper reiser4progs-2.0.4.tar.gz and generated one set of components for d-i I built the d-i image.
>
> Fact is, the installer throws an error in *both* bare metal and VirtualBox 6.1.16:
> ...
> Dec 22 20:19:56 main-menu[330]: INFO: Menu item 'bootstrap-base' selected
> Dec 22 20:19:56 debootstrap: /usr/sbin/debootstrap --components=main --debian-installer --resolve-deps --keyring=/usr/share/keyrings/archive.gpg buster /target http://deb.debian.org/debian/
> Dec 22 20:19:56 debootstrap: /usr/sbin/debootstrap: line 1596: /target/test-exec: Invalid argument
> Dec 22 20:19:56 kernel: [ 1018.632648] kernel read not supported for file /test-exec (pid: 10077 comm: debootstrap)
> Dec 22 20:19:56 debootstrap: E: NOEXEC
> Dec 22 20:19:56 debootstrap: EF: Cannot install into target '/target' mounted with noexec or nodev
> Dec 22 20:20:12 base-installer: error: exiting on error base-installer/debootstrap-failed
> Dec 22 20:20:14 main-menu[330]: WARNING **: Configuring 'bootstrap-base' failed with error code 1
> Dec 22 20:20:14 main-menu[330]: WARNING **: Menu item 'bootstrap-base' failed.
> Dec 22 20:20:15 main-menu[330]: INFO: Falling back to the package description for brltty-udeb

[...]

> Apparently, d-i [Debian-installer] complains about being unable to set the test file executable and causes the error when 1 is returned.
> Notwithstanding, I manually verified that I am able to touch a file and set it +x executable.
>
> Furthermore, tricking the function return value to 0 I am able to make d-i continue with the latest SFRN5 installation (see [*trick*] below); yet, subsequently halts again with
> an apparently related error --can not proceed any further.
>
> Digging deeper with dmesg, we can see that apparently it is the kernel which cannot 'read' properly. Please find a partial dmesg log with relevant output
> from an attempt on my physical development machine.
> ...
> [  508.614488] Loading Reiser4 (Software Framework Release: 5.1.3). See reiser4.wiki.kernel.org for a description of Reiser4.
> [  508.661951] SGI XFS with ACLs, security attributes, realtime, quota, no debug enabled
> [  509.326270] device-mapper: uevent: version 1.0.3
> [  509.326505] device-mapper: ioctl: 4.43.0-ioctl (2020-10-01) initialised: dm-devel@xxxxxxxxxx
> [  509.902828]  sda: sda1 sda2 sda3 sda4 sda5 sda6
> [  509.915300]  sdb: sdb1 sdb2 sdb3
> [  511.973360]  sdb: sdb1 sdb2 sdb3
> [  627.525371] Adding 9765884k swap on /dev/sda3.  Priority:-2 extents:1 across:9765884k FS
> [  636.240812] reiser4[mount(9430)]: reiser4_register_subvol (fs/reiser4/init_volume.c:222)[edward-1932]:
> [  636.240812] NOTICE: brick /dev/sda6 has been registered
> [  636.243003] reiser4 (sda6): found disk format 5.1.3.
> [  643.759971] reiser4 (/dev/sda6): using Hybrid Transaction Model.
> [  643.759980] reiser4: brick /dev/sda6 activated
> [  643.788537] EXT4-fs (sda1): mounting ext2 file system using the ext4 subsystem
> [  643.813474] EXT4-fs (sda1): mounted filesystem without journal. Opts: (null)
> [  643.813488] ext2 filesystem being mounted at /target/boot supports timestamps until 2038 (0x7fffffff)
> [  648.168730] kernel read not supported for file /test-exec (pid: 9876 comm: debootstrap) [*trick*]
> [  898.761385] reiser4: brick /dev/sda6 deactivated
> [  991.001332] reiser4 (sda6): found disk format 5.1.3.
> [  999.093471] reiser4 (/dev/sda6): using Hybrid Transaction Model.
> [  999.093480] reiser4: brick /dev/sda6 activated
> [ 1009.340117] EXT4-fs (sda1): mounting ext2 file system using the ext4 subsystem
> [ 1009.362722] EXT4-fs (sda1): mounted filesystem without journal. Opts: (null)
> [ 1009.362737] ext2 filesystem being mounted at /target/boot supports timestamps until 2038 (0x7fffffff)
> [ 6373.748413] kernel read not supported for file /test-exec (pid: 10094 comm: debootstrap)
> [ 6413.169920] kernel read not supported for file /usr/bin/true (pid: 15960 comm: chroot)


Hello.

This is because of VFS changes in Linux-5.10.X.
Specifically, because of the following patch:
https://lkml.org/lkml/2020/8/17/174
In the upstream git repository it is commit 4d03e3cc59828c82ee89ea6e2

So, Christoph, what to do now for file systems which implement
->read() method of file operations? It seems that chroot doesn't work
for them. And people are not able to release distros with upgraded
kernels..

Thanks,
Edward.