Arm News Archives
Arm SMCCC TRNG Driver Queued Ahead Of Linux 5.15

The Linux kernel already supports making use of Arm's True Random Number Generator (TRNG) SMCCC interface within the random seed code while for the upcoming Linux 5.15 cycle an "arm_smccc_trng" driver is being added and will allow exposing the entropy to user-space.

8 August 2021 - Arm SMCCC TRNG - Add A Comment
Arm Mali "Valhall" Reverse-Engineering Started

The Panfrost open-source Linux graphics driver stack has matured nicely for Arm Mali Midgard and Bifrost generations but for the past two years now there has been Valhall as the latest-generation Arm Mali microarchitecture. There is now work underway on reverse-engineering Valhall for ultimately wiring up with open-source graphics driver support.

20 July 2021 - Valhall Reverse Engineering - 22 Comments
ACPI CPPC CPUFreq Will Try Frequency Invariance Again For Linux 5.14

Frequency invariance support for the ACPI CPPC CPUFreq driver originally landed in Linux 5.13 but was reverted late in the cycle due to problems (possible kernel oops) while now that's been cleaned up and is trying again for Linux 5.14 with this functionality striving for more accurate load tracking.

8 July 2021 - ACPI CPPC Frequency Invariance - 4 Comments
Arm Neoverse V1 Tuning Lands In GCC 11 Compiler

In addition to AMD Zen 3 "znver3" seeing a lot of last minute tuning/optimization work ahead of the GCC 11 compiler being released as stable in the weeks ahead, Arm has also been getting some last minute work into this open-source compiler as it pertains to the Neoverse V1 support.

27 March 2021 - Neoverse V1 - 1 Comment
Linux Developers Continue Discussing "SLS" Mitigation For The Kernel

Disclosed by Arm last summer was the Straight Line Speculation (SLS) vulnerability and they were quick to introduce new safeguards against SLS in the GCC and LLVM compilers. The compiler-based mitigations to straight-line speculation involves adding speculation barrier sequences around the vulnerable instructions to prevent speculatively executing instructions around changes in control flow. While compiler developers were quick to add the options, so far the Linux kernel developers are in disagreement still over its importance and the proposed patches that would flip on this option when compiling the ARM Linux kernel.

6 March 2021 - Straight Line Speculation - 1 Comment
Google Engineers Propose Adding Linux Kernel Option For ARM SLS Mitigation

Made public last year was the Arm Straight Light Speculation (SLS) vulnerability. SLS with ARM hardware can result in speculative executing instructions following an unconditional change in control flow. The Linux kernel may soon have an option for enabling the mitigation of the Arm SLS vulnerability.

15 February 2021 - Straight-Line Speculation - 1 Comment
LLVM Adds Additional Protections For Arm's SLS Speculation Vulnerability Mitigation

Revealed earlier this year was the Arm Straight Line Speculation (SLS) vulnerability. SLS was a Google discovery for modern ARMv8 CPUs where speculative execution past unconditional changes in control flow could lead to information disclosure via side-channel analysis. Arm recommended compiler-based mitigations to insert speculation barriers after vulnerable instructions, which GCC and LLVM began adding opt-in protections right away. This weekend some additional SLS functionality was added for LLVM.

20 December 2020 - Straight Line Speculation - Add A Comment
Arm Neoverse V1 Support Added To LLVM Clang 12 Compiler

Announced by Arm back in September was the Neoverse V1 "Zeus" platform with 50%+ performance uplift over the Neoverse N1. Neoverse V1 also supports Scalable Vector Extensions (SVE) and other features in catering the platform for machine learning, cloud, HPC, and similar use-cases.

9 November 2020 - neoverse-v1 - Add A Comment

251 Arm news articles published on Phoronix.