kern/56232: Unstable system with tar on /dev

[rvp%SDF.ORG@localhost]

>Number:         56232
>Category:       kern
>Synopsis:       Unstable system with tar on /dev
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jun 03 22:20:00 +0000 2021
>Originator:     RVP
>Release:        NetBSD/amd64 9.99.82 (GENERIC)
>Organization:
>Environment:
NetBSD x202e.localdomain 9.99.82 NetBSD 9.99.82 (GENERIC) #0: Sat May  8 19:36:28 UTC 2021  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64
>Description:
Running tar on /dev causes unstable system behaviour (the keyboard locks up, or generates random keys when pressed).

/tmp# tar -C /dev -cf /dev/null .
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
tar: Couldn't list extended attributes: Invalid argument
/tmp# 

And, dmesg shows:

[   730.595589] WARNING: module error: incompatible module class 1 for `nvmm' (wanted 3)
[   730.595589] WARNING: module error: incompatible module class 1 for `nvmm' (wanted 3)
[   730.746121] iscsi: attached.  major = 203
[   730.796534] tap0: Ethernet address f2:0b:a4:70:cf:1c
[   730.796534] tap0: detached
[   730.805590] pad0: outputs: 44100Hz, 16-bit, stereo
[   730.805590] audio1 at pad0: playback
[   730.805590] audio1: slinear_le:16 -> slinear_le:16 2ch 44100Hz, blk 1764 bytes (10ms) for playback
[   730.805590] spkr2 at audio1: PC Speaker (synthesized)
[   730.805590] wsbell at spkr2 not configured
[   730.805590] spkr2: detached
[   730.805590] audio1: detached
[   730.805590] pad0: detached
[   730.805590] pad1: outputs: 44100Hz, 16-bit, stereo
[   730.805590] audio1 at pad1: playback
[   730.805590] audio1: slinear_le:16 -> slinear_le:16 2ch 44100Hz, blk 1764 bytes (10ms) for playback
[   730.805590] spkr2 at audio1: PC Speaker (synthesized)
[   730.805590] wsbell at spkr2 not configured
[   730.805590] spkr2: detached
[   730.805590] audio1: detached
[   730.805590] pad1: detached
[   730.805590] pad2: outputs: 44100Hz, 16-bit, stereo
[   730.805590] audio1 at pad2: playback
[   730.815590] audio1: slinear_le:16 -> slinear_le:16 2ch 44100Hz, blk 1764 bytes (10ms) for playback
[   730.815590] spkr2 at audio1: PC Speaker (synthesized)
[   730.815590] wsbell at spkr2 not configured
[   730.815590] spkr2: detached
[   730.815590] audio1: detached
[   730.815590] pad2: detached
[   730.815590] pad3: outputs: 44100Hz, 16-bit, stereo
[   730.815590] audio1 at pad3: playback
[   730.815590] audio1: slinear_le:16 -> slinear_le:16 2ch 44100Hz, blk 1764 bytes (10ms) for playback
[   730.815590] spkr2 at audio1: PC Speaker (synthesized)
[   730.815590] wsbell at spkr2 not configured
[   730.815590] spkr2: detached
[   730.815590] audio1: detached
[   730.815590] pad3: detached
[   730.915588] WARNING: module error: incompatible module class 2 for `zfs' (wanted 3)
[   730.915588] WARNING: module error: incompatible module class 2 for `zfs' (wanted 3)
[   730.935587] WARNING: module error: incompatible module class 1 for `lua' (wanted 3)
[   730.935587] WARNING: module error: incompatible module class 1 for `lua' (wanted 3)
[   730.955587] WARNING: module error: incompatible module class 2 for `autofs' (wanted 3)
[   730.955587] WARNING: module error: incompatible module class 2 for `autofs' (wanted 3)
[   730.995587] WARNING: module error: incompatible module class 1 for `dtrace' (wanted 3)
[   730.995587] WARNING: module error: incompatible module class 1 for `dtrace' (wanted 3)

>How-To-Repeat:
See above.
>Fix: