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Kernel Space: Bugs, Patches, and Engineering
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Tom's Hardware ☛ AMD confirms low-power CPU cores in Linux kernel patch — Zen 6 chips could follow in Intel's footsteps with new core type for background tasks
AMD confirms plans to incorporate low-power CPU cores into next-generation heterogeneous CPUs to lower power consumption and improve energy efficiency.
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AMD's heterogeneous processors identify CPU types using CPUID Function 0x80000026 (Extended CPU Topology), as EBX bits [31:28] carry the core classification. Up until recently, AMD only classified its cores as Performance and Efficiency, while the latest patch adds Low-Power cores. The patch enables Linux to distinguish between Performance, Efficiency, and Low-Power cores efficiently, and the latter are also correctly supported by AMD's performance management.
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Russell Coker ☛ Russell Coker: Dirty Clone and SE Linux
There is a new Linux kernel exploit out named Dirty Clone [1].
The first thing to do to exploit this is to create a container with a separate network namespace via one of the following commands: [...]
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University of Toronto ☛ As expected, using kexec to switch to a new Ubuntu kernel works
For a long time, I ignored kexec both for my own personal machines and at work. I knew it existed but I never attempted to use it. That changed recently when I realized we could use kexec to start a network (re)install environment without needing our servers to actually have network booting enabled (which they mostly don't currently, for historical reasons). This has led me to do some additional experimentation with kexec.
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Fergus Finn ☛ What happens when you run a CUDA kernel
A GPU does not take function calls like a CPU does. There is no entry point to jump to, and no stack to push arguments onto from the CPU. The GPU sits across a PCIe bus and reads a stream of driver commands out of host memory. Everything cuLaunchKernel does past this point is in service of getting one fully formed launch command into that stream, and then telling the GPU it has done so.
The first thing that needs to be done is loading the GPU code onto the device. The first time you run vadd, the driver copies across the kernel’s code: it allocates a buffer and copies the SASS in.
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AMD to Add Low Power Core Support for APUs to Linux
AMD has published a new series of patches for the Linux kernel, adding support for a completely new type of processor core—Low Power. This change is targeted at the company's upcoming heterogeneous processors and extends the existing x86 architecture topology code. Linux already recognizes Performance and Efficiency class cores, and now a third category will be added, which will no longer be detected as unknown.
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DirtyClone (CVE-2026-43503): Critical Linux Kernel Vulnerability Enables Local Privilege Escalation to Root on Major Distributions
A critical vulnerability in the Linux kernel, known as DirtyClone (CVE-2026-43503), enables local privilege escalation to root on most modern Linux distributions. Publicly disclosed by JFrog Security Research in June 2026, this flaw is a variant of the DirtyFrag family and is accompanied by a working proof-of-concept exploit. DirtyClone allows attackers with local code execution to corrupt file-backed memory via cloned network packets, bypassing file integrity tools and leaving minimal forensic traces. The vulnerability is particularly dangerous in multi-tenant servers, CI/CD runners, container hosts, and Kubernetes clusters. While exploitation has been confirmed by multiple security researchers, as of this writing, CISA does not list CVE-2026-43503 in its Known Exploited Vulnerabilities (KEV) catalog, so there is no CISA-confirmed active exploitation.
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Video Cardz ☛ AMD Linux patch adds Low Power CPU core type for future heterogeneous processors
AMD has posted a new Linux kernel patch series that adds support for a Low Power CPU core type. The change applies to AMD heterogeneous processors and expands the existing x86 topology code.
Linux already supports Performance and Efficiency core classifications.
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New Linux Support for Zen 6 "Low Power" Cores Lines Up with Previous PS6 Handheld Rumour
It's rumoured that Sony is working on both a handheld and a home console for the upcoming PlayStation 6 generation, so it was with considerable interest that tech outlet Guru3D spotted a new kernel patch detailing support for low power AMD CPU cores that could be used in the PlayStation 6 handheld.