Linus Benedict Torvalds injiniya yeFinnish-America, inozivikanwa nekutanga nekuchengetedza kuvandudzwa kweLinux kernel,
Mamwe mazuva apfuura Linus Torvalds akaita kuti maonero ake azivikanwe nezvekugumisa rutsigiro ye processor architecture i486 muLinux kernel. Chivakwa chekare chakakurukurwa mazuva mashoma apfuura mune shinda ichitarisa kuti kernel yaigona sei kubata zvishoma ichangoburwa kushandiswa (LRU) rondedzero, nzira yekuchengeta ndangariro mapeji.
Nguva Torvalds akaongorora kodhi yevabatsiri, zvinoratidzika kuva zvakavhiringidzwa nekudikanwa kwekusanganisira mhinduro zvakakwana kune vakura CPUs. Naizvozvo, akakurudzira kupedzisa kutsigirwa kwekiti yekare, inogona kunge iri nzira iri nyore yekugadzirisa nyaya dzendangariro.
“Takabvisa i386 support muna 2012. Pamwe yave nguva yekusiya i486 support muna2022? Linus Torvalds anodaro
Isu tinotoita (zvinobvumwa zvisirizvo: kwete SMP-yakachengeteka, kureva kuti ichashanda zvakanaka kunyangwe takatarisana nekuwana panguva imwe chete kubva kune dzakawanda tambo dzekuuraya, asi SMP Kirasi 486 michina haina kumbobvira yatsigirwa kunyangwe yaivepo nehunyanzvi)
Inofanira kuyeukwa kuti iyo i486 CPU yakatevedzana yakaburitswa muna 1989 uye parizvino mashoma mashoma ekugovera kweLinux akadai seGentoo, Slackware uye KNOPPIX ramba uchitsigira chivakwa ichi.
Maererano naTorvalds, matambudziko anokonzerwa nekutsigira zvivakwa zvechinyakare izvo vanhu vashoma vanoshandisa zvinogona kuve nyore kugadzirisa nekubvisa rutsigiro rwavo. LRU ndangariro manejimendi yevakuru processor zvakare ingave yakadaro.
Kutendeseka, ini handinganetse kukwidziridza izvo zvishoma zvinodiwa kuti isvike M586TSC, ndichisiya mamwe eaya ekutanga "ekunyepedzera Pentium" clones futi. Nekuti 'rdtsc' ingangove idambudziko rakaipisisa kupfuura CMPXCHG8B.
Uye ndizvo izvozvo zvese zvinodzika kusvika kucmpxchg8b, murairo unoenzanisa uye wobva wachinjana sere bytes (kana 64 bits) yeruzivo mundangariro dzekombuta. Nhengo yetsamba yetsamba Peter Zijlstra akataura kuti Linux inofanirwa kutsigira ma processors anokwanisa kuita izvi, achisiya 486-bit i32 kumashure uye zvichireva kuti nyowani Linux kernels yaizomhanya paP5 kirasi hardware kana nyowani.
Iyo cmpxchg8b rairo ndiye akonzeresa 'F00F' kukanganisa kubva kuPentium yepakutanga, umo CPU yakakanganisika isina masisitimu ekushandisa yakamira kushanda kusvika yatangwa patsva payakakurudzirwa kuita rairo.
Chaizvoizvo, ini handinzwisise zvachose kuti nei ma kernels azvino achimhanya pai486, sezvo ichiita senge exit_to_user_mode_prepare -> arch_exit_to_user_mode_prepare, uye inoguma iine isina mamiriro 'rdtsc' chirevo.
Ndinofunga kuti hausati waigonesa.RANDOMIZE_KSTACK_OFFSET*? Mune mamwe mazwi, yedu isiri-Pentium midhiya ine ACTIVED DECECTIVE AND BROKEN izvozvi.
Maererano naye, hazvina chokwadi kuti i486 hardware ichiri yakakosha. Hapana mubvunzo kuti pachine vanhu vakatsunga zvakadaro munyika, vanotenda kuti matambudziko anokonzerwa anogona kukundwa nyore nyore, asi kubva pakuona kwe kernel, nzvimbo iyi haina kunyanya kukosha.
"Saka ini handifunge kuti i486-kirasi hardware inoenderana. Ehe, ndine chokwadi kuti variko (Maciej muenzaniso), asi kubva pakukura kwe kernel maonero, handifunge kuti akanyatsokodzera. Pane imwe nguva, vanhu vanova nazvo sezvikamu zvemuseum. Vaigona zvakare kubata nuclei yemamuseum.
Zvinofanira kutaurwa kuti zvivakwa i486 yakatanga muna 1989 uye yakatsiviwa neIntel's Pentium muna 1993. Intel yakabvisa i486 muna 2007 uye nhasi Areka yayo yakakurumbira chigadzirwa dhatabhesi haina kutaurwa nezve processor mhuri.
Avo vachiri kushandisa zvishandiso kare kare vakasiya kuzviita pasina rutsigiro, pasina mukana wekutora kit nyowani kana kuti vanogadzira software vakafunga nezvepuratifomu.
Kuti uwane rumwe ruzivo, iyo Intel 80486 (i486, 486) imicroprocessor yemhuri yeX86, yakagadzirwa neIntel. Yakabudiswa muna 1989. Panyaya yekugadzira purosesa, 80486 yakafanana zvikuru neyakatangira, Intel 80386, pamwe nekuwedzera kwemamwe mirairo mishomanana. Icho, saka, chivakwa cheCISC.
Kubva pane microarchitectural point of view, pakave nekuvandudzwa kukuru panguva iyoyo: rairo yakabatana yakabatana uye cache yedata, sarudzo yakabatanidzwa Floating Point Processing Unit (FPU), uye yakagadziridzwa bhazi.
Pakupedzisira anotaura nezve vashandisi vane masisitimu ane i486 processors vachakwanisa kushandisa shanduro dzeLTS dzekernelizvo zvichagara kwemakore akawanda ari kuuya.
Tsigiro yemhando dzekare dzema processor uye zvishandiso zvinogona kubviswa kubva kuLinux kernel nekuda kwezvikonzero zvakasiyana, sekurerutsa nekugadzirisa kodhi, kuderedza kernel kuoma uye kugadzirisa, kana kutarisa kune zvimwe zvemazuva ano uye zvakakurumbira zvishandiso. Mimwe mienzaniso yemhando dzekare dzinogona kubviswa kubva kuLinux kernel rutsigiro dzinosanganisira:
Vakuru processors: seIntel i386, i486, kana mamwe ekare AMD processors. Aya ma processor asakara uye haatsigire zvichangoburwa zveLinux kernel.
Zvishandiso zvekare zvepaperipheral: Senge matepi madhiraivha, mafloppy drives, kana mamwe ekare ruzha kana makadhi evhidhiyo. Midziyo iyi haina kunyanya kuwanda nhasi, uye nekudaro rutsigiro rwavo runogona kubviswa kudzikisa kuoma kwekernel.
Ekare matekinoroji: akadai serutsigiro rweIPX network protocol, yaiwanzo shandiswa mumakombuta network makumi emakore apfuura. Sezvo matekinoroji achifambira mberi nekuchinja, tsigiro yematekinoroji akadzikiswa inogona kubviswa kubva kukernel.