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

[Edward Shishkin]

On 02/16/2021 04:56 PM, Jose R Rodriguez wrote:
> On Mon, 2021-02-08 at 17:03 +0100, Edward Shishkin wrote:
> > On 02/08/2021 01:54 PM, Metztli Information Technology wrote:
> > > On Wed, Dec 23, 2020 at 3:40 PM Edward Shishkin <
> > > edward.shishkin@xxxxxxxxx> wrote:
> > > > On 12/23/2020 05:01 PM, Metztli Information Technology wrote:
> > > > > Niltze [Ð—Ð´Ñ€Ð°Ð²Ñ Ñ‚Ð²ÑƒÐ¹Ñ‚Ðµ : 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?
> > >
> > > *deafening silence* it appears that -- in the best of cases --
> > > Christoph engaged in an act of _iter masturbation [1];
> > > and in the worst of cases, the gentleman was aiming straight at
> > > reiser4.
> > >
> > > > ... It seems that chroot doesn't work
> > > > for them. And people are not able to release distros with
> > > > upgraded
> > > > kernels..
> > >
> > > Not only 'chroot doesn't work' for us, but even after replacing the
> > > kernel in a reiser4 (proper SFRN ;) instance and
> > >    upon an initial Linux 5.10.x kernel boot:
> > > ...
> > > kernel read not supported for file usr/lib/systemd/systemd (pid: 1
> > > comm: run-init)
> > > kernel panic -- not syncing: Attempted to kill init!
> > > exitcod=0x00000100
> > > ...
> > >
> > > Fact is some of us have commercial interests when deploying
> > > reiser4, both in cloud instances, baremetal, and on-premises.
> > >
> > > In the future if -- and only if -- our reiser4 efforts come to
> > > successful fruition, quite likely in due time we will be
> > >    able to financially commit to the Penguin's Linux Foundation
> > > temple, just like large corporations do
> > >    in exchange for indulgences[2] which virtue-wash their past
> > > and/or current corp. officers' *substantially darker deeds*;
> > >    heck, 'indulgence trafficking' seems to assuage->numb->arg(STFU)
> > > that 'virtuous' cult of GNU/Linux
> > >    developers/gatekeepers/maintainers' frivolous, *narcissist*,
> > > ethics and/or moralities so often piled up against
> > >    Reiser's work --which, paradoxically(!?), actually was largely
> > > implemented by Russian developers ;)
> > >
> > > In the meantime, I hacked a reverse patch that undoes some(all) of
> > > the surreptitious lethal attack on reiser4 fs
> > >    -- at least on AMD64 architectures (I did away with other
> > > arch/Kconfigs).
> > > And no, I am not a git pro-, undoing what I could of commit
> > > 4d03e3cc59828c82ee89ea6e27a2f3cdf95aaadf (as your hinted, Ed)
> > >    does not fix the 'kernel read' issue.
> > >
> > > Notwithstanding, I would appreciate if you can take a look at the
> > > attached patch. Probably it can be streamlined and/or improved
> > >    further to minimize pain on subsequent Linux kernel upgrades.
> >
> >
> > That patch is an attempt to swim against the current ;)
> In a sense all of us who prefer reiser4 do not have a herd mentality.
> So, yes, we 'swim against the current', if you will put it in those
> terms, because we value data integrity (atomicity).


Cool.
Do you have resources to support such fork?


> Notwithstanding, it is only an ephemeral hack for AMD64 architectures.
> I have running locally reiser4 -enabled 5.10.13-2, 5.10.14-2, whereas I
> have an Google Compute Engine (GCE), on an AMD Epyc (reizer4 label)
> zone, custom instance testing with a cloud kernel 5.10.15-2.
>
> < https://metztli.it/buster/cloud-5.10.15-2+reizer4_0_2.png >
>
> Heck, I have updated the reiser4, Software Framework Release Number
> (SFRN) 5.1.3, d-i netboot installer media with a test kernel 5.10.16-2
> < https://metztli.it/buster-reiser5/5.10.x/metztli-reiser4-sfrn5-ng.iso


Note that fsck.reiser4 still doesn't work with 5.1.3

Thanks,
Edward.


> >
> <
> https://metztli.it/buster-reiser5/5.10.x/metztli-reiser4-sfrn5-ng.iso.SHA256SUM
> >
>
> ... крутые?
> > I no longer remember, why they want to get rid of set_fs for already
> > 15
> > years, but ->read() and ->write() methods seem to be deprecated, and
> > the
> > correct way would be to implement the new ->read_iter() and
> > write_iter()
> > methods, where reiser4 works with "chunked" streams, represented by
> > iov_iter structure, rather than with "continuous" streams,
> > represented
> > by char __user *buf. The task is not that difficult, but rather time
> > consuming - I don't have a time for this right now..
> >
> > Thanks,
> > Edward.
> >
> > > The patch has been tested in my local development machine
> > > environment --
> > >    as I intalled the generated reiser4 -enabled linux 5.10.13/14
> > > meta/kernel into a Debian Bullseye already running reiser4 (with
> > > proper SFRN)
> > >    and the kernel booted nicely. Subsequently, after installing the
> > > linux headers, etc. I built a couple of upgraded kernels
> > >    in Debian Buster GCC-8 and Bullseye GCC-10 environments -- thus
> > > the hack seems to be stable.
> > >
> > > Additionally, I have just made a Debian-Installer (d-i) with a
> > > 'kernel read' -patched Linux 5.10.14.1 which successfully installed
> > >    into a VirtualBox 6.1.18 VM:
> > > <
> > > https://metztli.it/buster/reiser4_0_2-linux-5.10.14-kernel-read-patched.png
> > >   >
> > >
> > > > Thanks,
> > > > Edward.
> > >
> > > Best Professional Regards.
> > >
> > > [1]
> > > "The bug was fixed, again way back in 2010, and over time chip-
> > > designers have moved on to improved memory management techniques.
> > > Torvalds wrote that this sort of memory space override has been
> > > banished from the x86, powerpc, s390 and RISC-V architectures."
> > > < https://www.theregister.com/2020/10/25/linux_5_10_rc1/ ;>
> > >
> > > [2] https://www.britannica.com/topic/indulgence
>
> Best Professional Regards.