64-bit ARM Changes For Linux 4.19 Has "A Bunch Of Good Stuff"

Written by Michael Larabel in Arm on 15 August 2018 at 07:49 AM EDT. Add A Comment
Will Deacon submitted the 64-bit ARM (ARM64/AArch64) changes on Tuesday for the Linux 4.19 kernel merge window.

The 64-bit ARM space on Linux remains as busy as ever. For this next kernel cycle, Deacon characterized the changes as "a bunch of good stuff in here." That good 64-bit ARM stuff for Linux 4.19 includes:

- ARM64 support for the new GCC STACKLEAK plug-in that was merged into gcc-plugins for Linux 4.19. The STACKLEAK compiler plug-in is able to fend off possible flaws/attacks pertaining to uninitialized stack usage, stack content leaking, and stack exhaustion/guard-page skipping. This mainline kernel STACKLEAK was ported from old GrSecurity/PaX code.

- Support for the Restartable Sequences system call. This new system call was originally added in Linux 4.18 and "RSEQ" allows for faster user-space operations on per-CPU data by providing a shared data structure ABI between each user-space thread and the kernel.

- A rewrite of their syscall entry code in C in order to zero out the GPR registers on entry from user-space.

- Kexec and Kdump now work on systems started without ACPI support.

- Qspinlock to replace their old ticket lock code.

- Support for chained PMU counters.

- Re-enabled support for huge vmalloc/IO mappings.

The complete list of patches can be found via the kernel mailing list.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via MichaelLarabel.com.

Popular News This Week