--- title: Linux Begins Seeing Workarounds For Fujitsu MONAKA CPU Bugs description: Linux kernel patches have begun appearing to work around three hardware bugs in Fujitsu's new 144-core Arm-based MONAKA CPU, aimed at AI infrastructure... canonical: https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Linux Begins Seeing Workarounds For Fujitsu MONAKA CPU Bugs | daily.dev og:description: Linux kernel patches have begun appearing to work around three hardware bugs in Fujitsu's new 144-core Arm-based MONAKA CPU, aimed at AI infrastructure... og:url: https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv og:image: https://api.daily.dev/og/posts/vgjX1LItv.png og:image:alt: Linux Begins Seeing Workarounds For Fujitsu MONAKA CPU Bugs og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Linux Begins Seeing Workarounds For Fujitsu MONAKA CPU Bugs **[Phoronix](https://daily.dev/sources/phoronix)** · 2 min read · 0 upvotes · 0 comments ## Summary Linux kernel patches have begun appearing to work around three hardware bugs in Fujitsu's new 144-core Arm-based MONAKA CPU, aimed at AI infrastructure servers. The fixes address a range-based TLBI invalidation failure (affecting 64K kernels), a PMU overflow misdetection that can trigger interrupt storms, and a possible CPU core hang tied to SGI handling races with higher-priority interrupts. CPU type detection for MONAKA is also being introduced in the kernel to apply these workarounds. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What CPU bugs does the Linux kernel work around for the Fujitsu MONAKA processor? The Linux kernel adds three workarounds for the Fujitsu MONAKA Arm server CPU: a range-based TLBI failure that fails to invalidate TLB entries when using a 64K kernel, a PMU overflow misdetection that can cause interrupt storms, and a possible CPU core hang caused by an SGI being lost when racing with a higher-priority interrupt or sleep-state transition. _Teams bringing up new Arm server CPUs can track kernel erratum workarounds like these on daily.dev._ ### Does the range-based TLBI bug affect all Fujitsu MONAKA kernel configurations? No, the TLB invalidation bug only appears when using a 64K page size kernel on the Fujitsu MONAKA CPU, requiring the kernel to issue extra TLBI instructions to guarantee entries are invalidated. A 64K kernel is still the recommended configuration for MONAKA for performance reasons despite this erratum. _Engineers tuning kernel page sizes for new Arm hardware can follow coverage like this on daily.dev._ ## Similar posts on daily.dev - [Linux Sees Patches For "Critical" Vulnerability Affecting Many Arm CPUs](https://daily.dev/posts/linux-sees-patches-for-critical-vulnerability-affecting-many-arm-cpus-i0fzrb307) · Phoronix · 4 upvotes · 0 comments - [The forgetful CPU \(Linux on M4\)](https://daily.dev/posts/the-forgetful-cpu-linux-on-m4--igqauax00) · Lobsters · 1 upvotes · 0 comments - [New Linux Patches Trying To Mainline Renesas SH7305 CPU Support](https://daily.dev/posts/new-linux-patches-trying-to-mainline-renesas-sh7305-cpu-support-tfzuo3b1g) · Phoronix · 0 upvotes · 0 comments - [AMD's new CPU core type just got unlocked on Linux before it was even announced](https://daily.dev/posts/amd-s-new-cpu-core-type-just-got-unlocked-on-linux-before-it-was-even-announced-kejwce9fl) · XDA Developers · 0 upvotes · 0 comments - [New type of attack can slip past the defenses in your computer’s processor](https://daily.dev/posts/new-type-of-attack-can-slip-past-the-defenses-in-your-computer-s-processor-hhyhhdxyi) · MIT News · 0 upvotes · 0 comments --- Tags: [#linux](https://daily.dev/tags/linux), [#hardware](https://daily.dev/tags/hardware) [View this post on daily.dev](https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Linux Begins Seeing Workarounds For Fujitsu MONAKA CPU Bugs","url":"https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv"},"datePublished":"2026-10-04T10:39:51.569Z","dateModified":"2026-10-04T10:40:15.771Z","description":"Linux kernel patches have begun appearing to work around three hardware bugs in Fujitsu's new 144-core Arm-based MONAKA CPU, aimed at AI infrastructure...","image":"https://media.daily.dev/image/upload/s--foaA6JGU--/f_auto/v1722860399/public/Placeholder%2004","thumbnailUrl":"https://media.daily.dev/image/upload/s--foaA6JGU--/f_auto/v1722860399/public/Placeholder%2004","isAccessibleForFree":true,"articleSection":"Phoronix","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Phoronix","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/6a26ba379dd64932830aa0c9803dd7ee","url":"https://daily.dev/sources/phoronix"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"linux,hardware","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Phoronix","item":"https://daily.dev/sources/phoronix"},{"@type":"ListItem","position":3,"name":"Linux Begins Seeing Workarounds For Fujitsu MONAKA CPU Bugs"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/linux-begins-seeing-workarounds-for-fujitsu-monaka-cpu-bugs-vgjx1litv#faq","mainEntity":[{"@type":"Question","name":"What CPU bugs does the Linux kernel work around for the Fujitsu MONAKA processor?","acceptedAnswer":{"@type":"Answer","text":"The Linux kernel adds three workarounds for the Fujitsu MONAKA Arm server CPU: a range-based TLBI failure that fails to invalidate TLB entries when using a 64K kernel, a PMU overflow misdetection that can cause interrupt storms, and a possible CPU core hang caused by an SGI being lost when racing with a higher-priority interrupt or sleep-state transition. 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