Hello,

After a recent upgrade, the linux-image-6.19.6+deb14+1-amd64 kernel was installed on my Forky laptop, but when I restart my machine, the old kernel, linux-image-6.19.6+deb14-amd64, is selected by default. So I have two questions:

Q1: Why isn't 6.19.6+deb14+1 selected by default?
(When I select it manually, it works fine.)

Q2: How can I make 6.19.6+deb14+1 the default kernel instead of linux-image-6.19.6+deb14-amd64 ?

Thanks.

--
Gerard
__________________________
**************************
Created with Mutt 2.2.13
under Debian Linux FORKY
**************************

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Mon, Mar 16, 2026 at 12:23:12AM +0100, Gerard ROBIN wrote:

Hello,

After a recent upgrade, the linux-image-6.19.6+deb14+1-amd64 kernel was installed on my Forky laptop, but when I restart my machine, the old kernel, linux-image-6.19.6+deb14-amd64, is selected by default. So I have two questions:

Did you do a reboot or a suspend/hibernate ? It must be a reboot.

Q1: Why isn't 6.19.6+deb14+1 selected by default?
(When I select it manually, it works fine.)

Q2: How can I make 6.19.6+deb14+1 the default kernel instead of linux-image-6.19.6+deb14-amd64 ?

Thanks.

--
Gerard
__________________________
**************************
Created with Mutt 2.2.13
under Debian Linux FORKY
**************************

--
Alain Williams
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#include <std_disclaimer.h>

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Hi Gerard,
Gerard ROBIN <g.robin3@free.fr> writes:

Hello,

After a recent upgrade, the linux-image-6.19.6+deb14+1-amd64 kernel was installed on my Forky laptop, but when I restart my machine, the old kernel, linux-image-6.19.6+deb14-amd64, is selected by default. So I have two questions:

Q1: Why isn't 6.19.6+deb14+1 selected by default?
(When I select it manually, it works fine.)

This seems to be due to the alphabetic sorting order. Considering the 2
kernel names:
,----[ Notice the place marked by ^ ]
| linux-image-6.19.6+deb14-amd64
| ^
| linux-image-6.19.6+deb14+1-amd64
| ^
`----
The ascii code of '+' is 43, and '-' is 45, so '-' is considered a
bigger value so it's placed in higher precedence.
(I hope the kernel team can find a better naming scheme, as this is
really confusing for most users.)

Q2: How can I make 6.19.6+deb14+1 the default kernel instead of linux-image-6.19.6+deb14-amd64 ?

You have a few options:
* Manually select the newer kernel in Grub during boot, and remove the
older kernel, and after that it will use "+deb14+1".
* Change the GRUB_DEFAULT value in `/etc/default/grub'.
- Find which entry the "+deb14+1" kernel is in /boot/grub/grub.cfg and
use the unique ID of that entry in GRUB_DEFAULT. I used the
following command and its output quoted below:
,----[ First line is the command I used ($ is the prompt) ]
| $ sudo grep "Debian" /boot/grub/grub.cfg
| menuentry 'Debian GNU/Linux' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-c381db16-07ef-4cd9-b5c3-1363344ecbe9' {
| submenu 'Advanced options for Debian GNU/Linux' $menuentry_id_option 'gnulinux-advanced-c381db16-07ef-4cd9-b5c3-1363344ecbe9' {
| menuentry 'Debian GNU/Linux, with Linux 6.19.6+deb14-amd64' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.19.6+deb14-amd64-advanced-c381db16-07ef-4cd9-b5c3-1363344ecbe9' {
| menuentry 'Debian GNU/Linux, with Linux 6.19.6+deb14-amd64 (recovery mode)' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.19.6+deb14-amd64-recovery-c381db16-07ef-4cd9-b5c3-1363344ecbe9' {
| menuentry 'Debian GNU/Linux, with Linux 6.19.6+deb14+1-amd64' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.19.6+deb14+1-amd64-advanced-c381db16-07ef-4cd9-b5c3-1363344ecbe9' {
| menuentry 'Debian GNU/Linux, with Linux 6.19.6+deb14+1-amd64 (recovery mode)' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-6.19.6+deb14+1-amd64-recovery-c381db16-07ef-4cd9-b5c3-1363344ecbe9' {
`----
Now this can get a little complicated as the new kernel entry is
nested in a submenu: you need to get the whole path of the unique
IDs, one from the "submenu", and one from the menuentry for
6.19.6+deb14+1-amd64, and use the format
"submenu_unique_id>menuentry_unique_id" (note the double quote is
required). For my case, it's like below:

GRUB_DEFAULT="gnulinux-advanced-c381db16-07ef-4cd9-b5c3-1363344ecbe9>gnulinux-6.19.6+deb14+1-amd64-advanced-c381db16-07ef-4cd9-b5c3-1363344ecbe9"
- Run `sudo update-grub' to let the new grub settings take effect.
After this, you should be using the newer kernel on your next boot.
Once you have the correct kernel, I would suggest that you remove the
older kernel(s), and set GRUB_DEFAULT back to 0, and run `sudo
update-grub' again to update it. Otherwise it will continue to use the
select kernel in future upgrades, which is mostly likely not what you
want.

Thanks.

--
Regards,
Xiyue Deng


--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Hi,

On Mon, Mar 16, 2026 at 12:23:12AM +0100, Gerard ROBIN wrote:

After a recent upgrade, the linux-image-6.19.6+deb14+1-amd64 kernel was installed on my Forky laptop, but when I restart my machine, the old kernel, linux-image-6.19.6+deb14-amd64, is selected by default. So I have two questions:

Q1: Why isn't 6.19.6+deb14+1 selected by default?
(When I select it manually, it works fine.)

Which bootloader do you use?

If it's grub, do you have a setting for GRUB_DEFAULT in
/etc/default/grub (or some other file included from it)?

Normally GRUB_DEFAULT is set to 0, which would be the 0th (first) entry,
which is the most recent (highest version number). If you have it set to something else, or to "saved", that might explain that.

If it is set to 0, is the newest kernel the actual top most entry in the generated /boot/grub/grub.cfg file?

Thanks,
Andy

--
https://bitfolk.com/ -- No-nonsense VPS hosting

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Mon, Mar 16, 2026 at 12:57:56AM +0000, Andy Smith wrote:

If it is set to 0, is the newest kernel the actual top most entry in the generated /boot/grub/grub.cfg file?

Yeah so as Xiyue Deng posted, the change in naming scheme will be
causing a different order of entries in the generated config, so
GRUB_DEFAULT=0 becomes less useful. Whoops! Thanks for running testing
to find this bug. ?

Thanks,
Andy

--
https://bitfolk.com/ -- No-nonsense VPS hosting

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Mon, Mar 16, 2026 at 03:35:19AM +0000, Andy Smith wrote:

version_sort is a bash function in /usr/share/grub/grub-mkconfig_lib:

Well, POSIX sh function I should say, as grub-mkconfig is currently a
/bin/sh script.

Thanks,
Andy

--
https://bitfolk.com/ -- No-nonsense VPS hosting

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Hi,

On Sun, Mar 15, 2026 at 10:02:50PM -0500, David Wright wrote:

Presumably, something in the process of writing grub.cfg
ought to be using dpkg --compare-versions rather than
plain ASCII sorting. (Not sure what that something would be.)

It's done by grub-mkconfig which calls /etc/grub.d/10_linux. An issue is
that this is only looking at filenames on the filesystem (not Debian
package versions):

list=
for i in /boot/vmlinuz-* /vmlinuz-* /boot/kernel-* ; do
if grub_file_is_not_garbage "$i" ; then list="$list $i" ; fi
done

then later:

reverse_sorted_list=$(echo $list | tr ' ' '\n' | sed -e 's/\.old$/ 1/; / 1$/! s/$/ 2/' | version_sort -r | sed -e 's/ 1$/.old/; s/ 2$//')

version_sort is a bash function in /usr/share/grub/grub-mkconfig_lib:

version_sort ()
{
case $version_sort_sort_has_v in
yes)
LC_ALL=C sort -V "$@";;
no)
LC_ALL=C sort -n "$@";;
*)
if sort -V </dev/null > /dev/null 2>&1; then
version_sort_sort_has_v=yes
LC_ALL=C sort -V "$@"
else
version_sort_sort_has_v=no
LC_ALL=C sort -n "$@"
fi;;
esac
}

So all in all a bit tricky to get Debian package versions into there and
maybe easier to correct the problem in the filenames.

Thanks,
Andy

--
https://bitfolk.com/ -- No-nonsense VPS hosting

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Thanks Xiyue for the advice. After thinking it over, I removed
kernel 6.19.6+deb14+1 since that's the one causing the problem.

Regards.

--
Gerard
__________________________
**************************
Created with Mutt 2.2.13
under Debian Linux FORKY
**************************

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Hi Andy,
Andy Smith <andy@strugglers.net> writes:

On Mon, Mar 16, 2026 at 03:35:19AM +0000, Andy Smith wrote:

version_sort is a bash function in /usr/share/grub/grub-mkconfig_lib:

Well, POSIX sh function I should say, as grub-mkconfig is currently a
/bin/sh script.

Thanks for the analysis!
FWIW, I have filed Bug#1131008. Hope the kernel team will find a solution.

Thanks,
Andy

--
Regards,
Xiyue Deng


--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Hi Gerard,
Gerard ROBIN <g.robin3@free.fr> writes:

Thanks Xiyue for the advice. After thinking it over, I removed
kernel 6.19.6+deb14+1 since that's the one causing the problem.

I would hope you would get rid of the older one (6.19.6+deb14) as the
newer one contains many apparmor fixes[1]. Or at least you should keep linux-image-amd64 installed so that newer kernels still get installed automatically.
In any case, I have filed Bug#1131008. Hopefully this will be fixed in
the future.
[1] https://tracker.debian.org/news/1728818/accepted-linux-6196-2-source-into-unstable/
[2] https://bugs.debian.org/1131008

Regards.

--
Regards,
Xiyue Deng


--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)