Why is libc6 2.33 necessary?

Asked by peter van olmen

Installation of new kernels was without problems up until now. Now I get an error that the headers are not being installed because libc6 2.33 is required and I'm only on Ubuntu 20.04.3 with libc6 2.31.
So I cannot install new kernel any more. I'm now on kernel 5.11.16. Latest is 5.12.
As far as I know this is not a kernel problem, but something you changed in Mainline Kernel Installer.
Why? And is this really necessary or can you revert this? Because now, me, and a lot of other users are blocked.
Best regards.

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Manfred Hampl (m-hampl) said :
#1
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Best Manfred Hampl (m-hampl) said :
#2

Looking into the packages, e.g. amd64/linux-headers-5.12.1-051201-generic_5.12.1-051201.202105021030_amd64.deb on https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.12.1/ I see that the headers-generic package has

Depends: linux-headecrs-5.12.1-051201, libc6 (>= 2.33), libelf1 (>= 0.142), libssl1.1 (>= 1.1.0), zlib1g (>= 1:1.2.3.3)

So it is the headers package that has the dependency, not the Mainline Kernel Installer

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peter van olmen (peterpov) said :
#3

Okay, I see. Thank you.
And is it safe to continue to install new kernels without the headers? I don't know what they are used for...

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Manfred Hampl (m-hampl) said :
#4

The "image" package contains the files needed for booting.
The "modules" package contains additional device drivers
The "headers" package contains certain program source parts that are necessary if you want to compile additional device drivers (e.g. needed for dkms, virtualbox, Broadcom WLAN drivers that you download from github, ...)

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peter van olmen (peterpov) said :
#5

Thank you,
I'll try to install the latest kernel then without the headers, as I don't compile anything. See what it gives and revert back if it gives problems.

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Kevin Hester (kevinh) said :
#6

Though to be clear, without a working dkms it won't be possible to install run popular packages like VirtualBox.

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peter van olmen (peterpov) said :
#7

Is there actually a reason why the headers need libc6 2.33 now? What changed between kernel 5.11.16 which I have installed with headers, and 5.11.17 which needs libc6 2.33?
I'm running 5.12.1 by the way without headers, there's a FAILED warning during startup, but it's to fast to read, and I have no problems at the moment.

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Manfred Hampl (m-hampl) said :
#8

"there's a FAILED warning during startup"

Can you check the system log or dmesg whether you find this message there, that you know what it is about?

I doubt that it is related to the fact that the headers package arte not installed.

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Manfred Hampl (m-hampl) said (last edit ):
#9

"Is there actually a reason why the headers need libc6 2.33 now? "

https://askubuntu.com/a/1335849/285965 writes something about changes in /lib/modules/5.11.18-generic/build/scripts/basic/fixdep and /lib/modules/5.11.18-generic/build/scripts/mod/modpost

I do not know whether this is the reason and if this is really necessary.

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Paul Ubuntu (paulubuntu2) said :
#10

Same issues with 18.04.5 and 5.11.17 and above with nvidia.