1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Linux 3.3-rc4 Kernel Fixes A Peculiar 32-bit Bug

Linux Kernel

Published on 18 February 2012 08:22 PM EST
Written by Michael Larabel in Linux Kernel
3 Comments

The Linux 3.3-rc4 kernel was released this Saturday evening after a peculiar 32-bit kernel bug had led to the release being delayed by a few days.

Linus Torvalds and others spent the past few days tracking down a complicated issue with the Linux 3.3 kernel whereby there would be floating-point state corruption resulting in a range of nasty problems. This FP corruption would result in crashes, Flash problems within the browser, the X input cursor moving sporadically, or other random issues.

This issue was tracked down to using a 32-bit x86 kernel on modern CPUs that support the AES-NI instruction set. Besides needing to be on a 32-bit AES-NI-capable kernel for CPUs that support the Advanced Encryption Standard instruction set, you also need to be using a wireless kernel driver that can utilize this hardware-acceleration for Advanced Encryption Standard encryption/decryption. When all these factors are met, you might have encountered this bug, which is fortunately now expected to be addressed in 3.3-rc4 and should in time be back-ported to stable kernels.

Intel supports AES-NI on their modern Sandy Bridge and most Clarkdale/Arrandale/Gulftown CPUs and AMD provides support for AES-NI with Bulldozer. All of these CPUs support x86_64, so you really should be using a 64-bit Linux kernel anyways and not a 32-bit kernel. If you still are using a 32-bit kernel on recent Intel/AMD hardware you should really consider moving to a 64-bit x86 kernel.

Besides fixing this 32-bit-kernel-with-AES-NI-and-WiFi-driver-causing-havoc bug, the 3.3-rc4 carries a variety of other bug-fixes too. There isn't anything else that stands out too much, although the old GMA500 driver was removed from staging now that there's the better Poulsbo driver. The old POHMELFS code was also dropped since now there's the new POHMELFS file-system.

One graphics-related note is that the Intel DRM driver with the Linux 3.3-rc4 kernel has decided to disable frame-buffer compression (FBC) for Sandy Bridge hardware as it's causing BLT ring problems with it running many times slower (up to 100x slower) or frequent lock-ups. The Intel developers aren't sure why having FBC causes the problem for Sandy Bridge, but this is their interim fix.

The Linux 3.3-rc4 kernel release announcement can be read at LKML.org. Some of the new features of the forthcoming Linux 3.3 kernel are talked about in this Phoronix article.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. Intel Xeon E5-1680 v3 & E5-2687W v3 Compared To The Core i7 5960X On Linux
  2. Intel 120GB 530 Series SSD Linux Performance
  3. Btrfs/EXT4/XFS/F2FS RAID 0/1/5/6/10 Linux Benchmarks On Four SSDs
  4. AMD's Windows Catalyst Driver Remains Largely Faster Than Linux Drivers
Latest Linux Articles
  1. NVIDIA vs. Nouveau Drivers With Linux 3.18 + Mesa 10.4-devel
  2. Is The Open-Source NVIDIA Driver Fast Enough For Steam On Linux Gaming?
  3. Linux 3.18 File-System Performance Minimally Changed But Possible Regressions
  4. AMD Radeon Gallium3D Is Catching Up & Sometimes Beating Catalyst On Linux
Latest Linux News
  1. Linux 3.18-rc6 Released, A Worrisome Regression Remains
  2. HandBrake 0.10 Brings H.265 & VP8 Encoders
  3. Gngr: A New Web Browser Focused On Privacy
  4. Linux 3.18 Kernel: Not Much Change With Intel Haswell Performance
  5. More File-System Tests Of The Linux 3.18 Kernel
  6. Using NVIDIA's NVENC On Linux With FFmpeg
  7. There's Talk Again About An "Open To The Core" Ubuntu Laptop
  8. PowerVR SGX Driver Code Gets Leaked
  9. V2 Of KDBUS Published For Linux Kernel Review
  10. VirtualBox 4.3.20 Arrives, Still No Sign Of VirtualBox 4.4
Latest Forum Discussions
  1. PulseAudio 6.0 Is Coming & Other Linux Audio Plans For The Future
  2. Debian Developer Resigns From The Systemd Maintainership Team
  3. Roadmap to Catalyst 14.10 ?
  4. Updated and Optimized Ubuntu Free Graphics Drivers
  5. Cant get working Kaveri APU - A10-7850k
  6. Script for Fan Speed Control
  7. Debian Init System Coupling Vote Results
  8. The Slides Announcing The New "AMDGPU" Kernel Driver