I don't use Ubuntu kernels; build my own mainline but work on kernel issues in mainline and Debian. I tested 144..157 length (interestingly although arm64 professes to support 2048 characters the kernel messages are truncated at around 1000 so don't show the entire thing).
$ qemu-system-aarch64 -machine virt,gic-version=3 -cpu max,pauth-impdef=on -smp 2 -m 4096 -nographic -kernel /srv/NAS/Sunny/SourceCode/builds/linux-aarch64/arch/arm64/boot/Image -append "debug $( for l in {144..157}; do echo -n param$l=$(pwgen $((l-9)) 1)' '; done )" -initrd rootfs/boot/initrd.img-6.8.12-arm64-debug
[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x000f0510]
[ 0.000000] Linux version 6.8.12 (<email address hidden>) (aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #10 SMP Fri
Jul 26 13:57:53 BST 2024
[ 0.000000] random: crng init done
[ 0.000000] Machine model: linux,dummy-virt
...
[ 0.000000] Kernel command line: debug param144=aixootoo9ii0dieghaem2eehahqu9Aejeuka3ui8chain9ief3Ooth9lahgeiyiew3dio3PhahpeiShoh1ootoch2rae9quushei9yu4ge5uasi9peizooT8JohjieMuGh7ohs7 param145=noohieL5DaeghaeGh4nueQuugoowohj6fa0Jaive7meaghukoog8tho6De6ahga7sheighah2Raing9eitai3eeHi4Ahr7aixaiLoh3cheeG
hosa9eR4sohkajahwe1tha9aotha param146=taesaekie3Vaiv2Neejohph0ozeile5daemu8beepha9Ojae8niev8nepaidaemu9uphaah4bongeiRahM5eichahTah6aegob8edee2xah6UaxahThee2puePua5ahchoqueixee param147=ahZai6EeW1EejaGh6hen6eu6oov6wo3ooph5theide6OhGh5oog2Iel8oong1ighooboo7ohthoh2le5eeloog1agha0phaid5enaeQuohfoo3EijaemeiZ
9ohG5aichoo9shuiFee param148=ieT6oogat5sheng9aeteigh4poohoongul5za7Eich5Abo2Aeraec0eingah5ahsh4Ooth9Phaithai3gethoo4piphie0zieHieYahngahbiitheingooshau4
chaepee2zeeWei5a param149=eenga3ku8deongie7Oovahsoo7ao1zail8remu2ieshai6haemee2eingoophev6eeY5KeeChiemeu2Eaquuqu8ahk3oohovoh6vaijaexoodeesoetuucie7geeba
h5cad5aikoh6mo param150=oopaiCh0thu1ioneed3apee9igieT7OaWedeemoop4izex9gaeRaequai6aavaephua4ahlooThaiquie4Gu8Eiyo8ohmai1aiye
...
[ 3.045515] Run /init as init process
[ 3.045717] with arguments:
[ 3.045852] /init
[ 3.045962] with environment:
[ 3.046098] HOME=/
[ 3.046206] TERM=linux
[ 3.046320] param144=aixootoo9ii0dieghaem2eehahqu9Aejeuka3ui8chain9ief3Ooth9lahgeiyiew3dio3PhahpeiShoh1ootoch2rae9quushei9yu4ge5uasi9peizooT8Johj
ieMuGh7ohs7
[ 3.046913] param145=noohieL5DaeghaeGh4nueQuugoowohj6fa0Jaive7meaghukoog8tho6De6ahga7sheighah2Raing9eitai3eeHi4Ahr7aixaiLoh3cheeGhosa9eR4sohkajah
we1tha9aotha
[ 3.047481] param146=taesaekie3Vaiv2Neejohph0ozeile5daemu8beepha9Ojae8niev8nepaidaemu9uphaah4bongeiRahM5eichahTah6aegob8edee2xah6UaxahThee2puePua
5ahchoqueixee
[ 3.047963] param147=ahZai6EeW1EejaGh6hen6eu6oov6wo3ooph5theide6OhGh5oog2Iel8oong1ighooboo7ohthoh2le5eeloog1agha0phaid5enaeQuohfoo3EijaemeiZ9ohG5
aichoo9shuiFee
[ 3.048466] param148=ieT6oogat5sheng9aeteigh4poohoongul5za7Eich5Abo2Aeraec0eingah5ahsh4Ooth9Phaithai3gethoo4piphie0zieHieYahngahbiitheingooshau4c
haepee2zeeWei5a
[ 3.048992] param149=eenga3ku8deongie7Oovahsoo7ao1zail8remu2ieshai6haemee2eingoophev6eeY5KeeChiemeu2Eaquuqu8ahk3oohovoh6vaijaexoodeesoetuucie7gee
bah5cad5aikoh6mo
[ 3.049508] param150=oopaiCh0thu1ioneed3apee9igieT7OaWedeemoop4izex9gaeRaequai6aavaephua4ahlooThaiquie4Gu8Eiyo8ohmai1aiyeib9ahkaifeh3ahqu5joutugh
1hee7ShiePhieThai
[ 3.050024] param151=aiVeiT2Aw0EenaizeeKaezei8eigei2Luov0ohdeeng6miekooZuD9ieci3oph6pahs9upid6Aesou6uiboongei7aVie2ushai8iex3quahzieH5eingaengao2
OhsheiHoo4Hiehei6N
[ 3.050564] param152=eivohroQui8quoh5jeizoo1ook6toothahchei3Iethee6au6irae3quee8AhLae9FaceuZahsahqueig9iec1jae9fier9Ohmaengohpheing4eimaipah3pahs
h4uo1Eefauroong1hiz
[ 3.051316] param153=juh6ahbu2raena5uocejaqueeduyohB6uasiex5ahtaiTieK3Ruol1ceijin4quah3Fee7ahthaiphoo8piaghaegomeez3aichee4doreiloh6dieL5chae0oor
ahth1shoz7cheesarood
[ 3.051860] param154=ainaa7XahH8phoobeefaebaepaivee9kierohse7OopooshahphiengogahThood6qua3woh5aiziungae1sai6ao7phahW0Ooph6fahk0uph3wieghai1ootoh4
Oogei6Jaeboupheehepho
[ 3.052373] param155=zienga1nee1CaiFeiv7Kae8ohma2ceejeif3pung2zi2shoigohn6choh6Oon7iaxie1Kua2waFoophier0uaf9aivoh1cee9chooha1phughohx8Abei9de9lai
kuaz6pheeD3pohbeic7sah
[ 3.052903] param156=aiyahy5ieghoo5eenaipethei7chebi4thaek5iqu5eelah5au3Eishil5Aichae3guqueiPei2ahdeeghiteequeichooWah2othee1thee4Zohgo5deem9aigh
0eef2sha2wei0sed8aiquoo
[ 3.053432] param157=iiph5iewudai5SahbiY4holoos3nis2Caeheibav0eu9EijaebahzeBuathei7xohngah
...
BusyBox v1.35.0 (Debian 1:1.35.0-4+b3) built-in shell (ash)
Enter 'help' for a list of built-in commands.
I don't use Ubuntu kernels; build my own mainline but work on kernel issues in mainline and Debian. I tested 144..157 length (interestingly although arm64 professes to support 2048 characters the kernel messages are truncated at around 1000 so don't show the entire thing).
$ qemu-system-aarch64 -machine virt,gic-version=3 -cpu max,pauth-impdef=on -smp 2 -m 4096 -nographic -kernel /srv/NAS/ Sunny/SourceCod e/builds/ linux-aarch64/ arch/arm64/ boot/Image -append "debug $( for l in {144..157}; do echo -n param$l=$(pwgen $((l-9)) 1)' '; done )" -initrd rootfs/ boot/initrd. img-6.8. 12-arm64- debug linux-gnu- gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #10 SMP Fri aixootoo9ii0die ghaem2eehahqu9A ejeuka3ui8chain 9ief3Ooth9lahge iyiew3dio3Phahp eiShoh1ootoch2r ae9quushei9yu4g e5uasi9peizooT8 JohjieMuGh7ohs7 param145= noohieL5Daeghae Gh4nueQuugoowoh j6fa0Jaive7meag hukoog8tho6De6a hga7sheighah2Ra ing9eitai3eeHi4 Ahr7aixaiLoh3ch eeG hwe1tha9aotha param146= taesaekie3Vaiv2 Neejohph0ozeile 5daemu8beepha9O jae8niev8nepaid aemu9uphaah4bon geiRahM5eichahT ah6aegob8edee2x ah6UaxahThee2pu ePua5ahchoqueix ee param147= ahZai6EeW1EejaG h6hen6eu6oov6wo 3ooph5theide6Oh Gh5oog2Iel8oong 1ighooboo7ohtho h2le5eeloog1agh a0phaid5enaeQuo hfoo3EijaemeiZ ieT6oogat5sheng 9aeteigh4poohoo ngul5za7Eich5Ab o2Aeraec0eingah 5ahsh4Ooth9Phai thai3gethoo4pip hie0zieHieYahng ahbiitheingoosh au4 eenga3ku8deongi e7Oovahsoo7ao1z ail8remu2ieshai 6haemee2eingoop hev6eeY5KeeChie meu2Eaquuqu8ahk 3oohovoh6vaijae xoodeesoetuucie 7geeba oopaiCh0thu1ion eed3apee9igieT7 OaWedeemoop4ize x9gaeRaequai6aa vaephua4ahlooTh aiquie4Gu8Eiyo8 ohmai1aiye aixootoo9ii0die ghaem2eehahqu9A ejeuka3ui8chain 9ief3Ooth9lahge iyiew3dio3Phahp eiShoh1ootoch2r ae9quushei9yu4g e5uasi9peizooT8 Johj noohieL5Daeghae Gh4nueQuugoowoh j6fa0Jaive7meag hukoog8tho6De6a hga7sheighah2Ra ing9eitai3eeHi4 Ahr7aixaiLoh3ch eeGhosa9eR4sohk ajah taesaekie3Vaiv2 Neejohph0ozeile 5daemu8beepha9O jae8niev8nepaid aemu9uphaah4bon geiRahM5eichahT ah6aegob8edee2x ah6UaxahThee2pu ePua ahZai6EeW1EejaG h6hen6eu6oov6wo 3ooph5theide6Oh Gh5oog2Iel8oong 1ighooboo7ohtho h2le5eeloog1agh a0phaid5enaeQuo hfoo3EijaemeiZ9 ohG5 ieT6oogat5sheng 9aeteigh4poohoo ngul5za7Eich5Ab o2Aeraec0eingah 5ahsh4Ooth9Phai thai3gethoo4pip hie0zieHieYahng ahbiitheingoosh au4c eenga3ku8deongi e7Oovahsoo7ao1z ail8remu2ieshai 6haemee2eingoop hev6eeY5KeeChie meu2Eaquuqu8ahk 3oohovoh6vaijae xoodeesoetuucie 7gee oopaiCh0thu1ion eed3apee9igieT7 OaWedeemoop4ize x9gaeRaequai6aa vaephua4ahlooTh aiquie4Gu8Eiyo8 ohmai1aiyeib9ah kaifeh3ahqu5jou tugh aiVeiT2Aw0Eenai zeeKaezei8eigei 2Luov0ohdeeng6m iekooZuD9ieci3o ph6pahs9upid6Ae sou6uiboongei7a Vie2ushai8iex3q uahzieH5eingaen gao2 eivohroQui8quoh 5jeizoo1ook6too thahchei3Iethee 6au6irae3quee8A hLae9FaceuZahsa hqueig9iec1jae9 fier9Ohmaengohp heing4eimaipah3 pahs juh6ahbu2raena5 uocejaqueeduyoh B6uasiex5ahtaiT ieK3Ruol1ceijin 4quah3Fee7ahtha iphoo8piaghaego meez3aichee4dor eiloh6dieL5chae 0oor arood ainaa7XahH8phoo beefaebaepaivee 9kierohse7Oopoo shahphiengogahT hood6qua3woh5ai ziungae1sai6ao7 phahW0Ooph6fahk 0uph3wieghai1oo toh4 ehepho zienga1nee1CaiF eiv7Kae8ohma2ce ejeif3pung2zi2s hoigohn6choh6Oo n7iaxie1Kua2waF oophier0uaf9aiv oh1cee9chooha1p hughohx8Abei9de 9lai eic7sah aiyahy5ieghoo5e enaipethei7cheb i4thaek5iqu5eel ah5au3Eishil5Ai chae3guqueiPei2 ahdeeghiteequei chooWah2othee1t hee4Zohgo5deem9 aigh d8aiquoo iiph5iewudai5Sa hbiY4holoos3nis 2Caeheibav0eu9E ijaebahzeBuathe i7xohngah
[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x000f0510]
[ 0.000000] Linux version 6.8.12 (<email address hidden>) (aarch64-
Jul 26 13:57:53 BST 2024
[ 0.000000] random: crng init done
[ 0.000000] Machine model: linux,dummy-virt
...
[ 0.000000] Kernel command line: debug param144=
hosa9eR4sohkaja
9ohG5aichoo9shuiFee param148=
chaepee2zeeWei5a param149=
h5cad5aikoh6mo param150=
...
[ 3.045515] Run /init as init process
[ 3.045717] with arguments:
[ 3.045852] /init
[ 3.045962] with environment:
[ 3.046098] HOME=/
[ 3.046206] TERM=linux
[ 3.046320] param144=
ieMuGh7ohs7
[ 3.046913] param145=
we1tha9aotha
[ 3.047481] param146=
5ahchoqueixee
[ 3.047963] param147=
aichoo9shuiFee
[ 3.048466] param148=
haepee2zeeWei5a
[ 3.048992] param149=
bah5cad5aikoh6mo
[ 3.049508] param150=
1hee7ShiePhieThai
[ 3.050024] param151=
OhsheiHoo4Hiehei6N
[ 3.050564] param152=
h4uo1Eefauroong1hiz
[ 3.051316] param153=
ahth1shoz7chees
[ 3.051860] param154=
Oogei6Jaebouphe
[ 3.052373] param155=
kuaz6pheeD3pohb
[ 3.052903] param156=
0eef2sha2wei0se
[ 3.053432] param157=
...
BusyBox v1.35.0 (Debian 1:1.35.0-4+b3) built-in shell (ash)
Enter 'help' for a list of built-in commands.
(initramfs) cat /proc/cmdline aixootoo9ii0die ghaem2eehahqu9A ejeuka3ui8chain 9ief3Ooth9lahge iyiew3dio3Phahp eiShoh1ootoch2r ae9quushei9yu4g e5uasi9peizooT8 JohjieMuGh7ohs7 param145= noohieL5Daeghae Gh4nueQuugoowoh j6fa0Jaive7meag hukoog8tho6De6a hga7sheighah2Ra ing9eitai3eeHi4 Ahr7aixaiLoh3ch eeGhosa9eR4sohk ajahwe1tha9aoth a param146= taesaekie3Vaiv2 Neejohph0ozeile 5daemu8beepha9O jae8niev8nepaid aemu9uphaah4bon geiRahM5eichahT ah6aegob8edee2x ah6UaxahThee2pu ePua5ahchoqueix ee param147= ahZai6EeW1EejaG h6hen6eu6oov6wo 3ooph5theide6Oh Gh5oog2Iel8oong 1ighooboo7ohtho h2le5eeloog1agh a0phaid5enaeQuo hfoo3EijaemeiZ9 ohG5aichoo9shui Fee param148= ieT6oogat5sheng 9aeteigh4poohoo ngul5za7Eich5Ab o2Aeraec0eingah 5ahsh4Ooth9Phai thai3gethoo4pip hie0zieHieYahng ahbiitheingoosh au4chaepee2zeeW ei5a param149= eenga3ku8deongi e7Oovahsoo7ao1z ail8remu2ieshai 6haemee2eingoop hev6eeY5KeeChie meu2Eaquuqu8ahk 3oohovoh6vaijae xoodeesoetuucie 7geebah5cad5aik oh6mo param150= oopaiCh0thu1 eT7OaWedeemoop4 izex9gaeRaequai 6aavaephua4ahlo oThaiquie4Gu8Ei yo8ohmai1aiyeib 9ahkaifeh3ahqu5 joutugh1hee7Shi ePhieThai param151= aiVeiT2Aw0Eenai zeeKaezei8eigei 2Luov0ohdeeng6m iekooZuD9ieci3o ph6pahs9upid6Ae sou6uiboongei7a Vie2ushai8iex3q uahzieH5eingaen gao2OhsheiHoo4H iehei6N param152= eivohroQui8quoh 5jeizoo1ook6too thahchei3Iethee 6au6irae3quee8A hLae9FaceuZahsa hqueig9iec1jae9 fier9Ohmaengohp heing4eimaipah3 pahsh4uo1Eefaur oong1hiz param153= juh6ahbu2raena5 uocejaqueeduyoh B6uasiex5ahtaiT ieK3Ruol1ceijin 4quah3Fee7ahtha iphoo8piaghaego meez3aichee4dor eiloh6dieL5chae 0oorahth1shoz7c heesarood param154=ainaa7XahH aivee9kierohse7 Oopooshahphieng ogahThood6qua3w oh5aiziungae1sa i6ao7phahW0Ooph 6fahk0uph3wiegh ai1ootoh4Oogei6 Jaeboupheehepho param155=zienga1 8ohma2ceejeif3p ung2zi2shoigohn 6choh6Oon7iaxie 1Kua2waFoophier 0uaf9aivoh1cee9 chooha1phughohx 8Abei9de9laikua z6pheeD3pohbeic 7sah param156= aiyahy5ieghoo5e enaipethei7cheb i4thaek5iqu5eel ah5au3Eishil5Ai chae3guqueiPei2 ahdeeghiteequei chooWah2othee1t hee4Zohgo5deem9 aigh0eef2sha2we i0sed8aiquoo param157= iiph5iewudai5Sa hbiY4holoos3nis 2Caeheibav0eu9E ijaebahzeBuathe i7xohngah
debug param144=
ioneed3apee9igi
8phoobeefaebaep
nee1CaiFeiv7Kae
(initramfs) cat /proc/cmdline | wc -c
2048