Injiniyan Meta akan jerin aika saƙonnin mai haɓaka kernel Linux Na lura da matsala game da umarnin RDSEED a cikin na'urori masu sarrafawa na AMD bisa ga tsarin Zen 5 microarchitecture. A cikin gwaje-gwajen da aka gudanar, umarnin RDSEED, wanda ke ba da damar shiga janareta entropy na hardware, ya dawo da 0 tare da nasarar alamar kammala aiki (CF=1) a cikin 10% na lokuta. Tunda 0 kuma ana dawo da shi lokacin da ba za a iya dawo da ingantaccen lamba bazuwar ba, kuma wannan yanayin an nuna shi ta hanyar tutar kammala aiki daban (CF=0), ana ɗauka cewa na'urori masu sarrafawa na AMD suna da kwaro wanda ke sa a tantance matsayin aiki ba daidai ba.
A cikin zuciyar Linux Ana amfani da umarnin a matsayin ɗaya daga cikin abubuwan da ake amfani da su wajen samar da entropy a cikin manhajar samar da lambar bazuwar da aka yi amfani da ita. Akwai hanyoyi da yawa na entropy, don haka matsalar RDSEED ba ta shafi ingancin lambobin bazuwar da kernel ya samar ba. An fitar da wani faci ga kernel wanda ke hana amfani da umarnin RDSEED akan tsarin da ke da wasu na'urori masu sarrafawa na AMD bisa ga tsarin Zen 5 microarchitecture.
An fara gano batun a cikin AMD EPYC Turin CPUs amma daga baya aka maimaita shi akan wani samfurin AMD CPU tare da microarchitecture iri ɗaya. Don haka, maimakon zaɓin kashe shi, an ba da shawarar a kashe RDSEED akan duk na'urori masu sarrafawa na AMD Zen 5. Yana da mahimmanci a lura cewa an gudanar da gwajin daidaitaccen aiki na RDSEED akan na'urori daban-daban yayin binciken wani batun RDSEED wanda ya taso a cikin Zen2 Cyan Skillfish CPUs kuma, a wasu lokuta, ya haifar da dawowar 0xffffffff kawai. A baya can, masu sarrafa AMD suna da matsala tare da umarnin RDRAND ba sa aiki da kyau bayan dawowa daga yanayin barci.
source: budenet.ru
