The 4.0 kernel has been released

[Posted April 13, 2015 by corbet]

Linus has released the 4.0 kernel right on schedule. "Feature-wise, 4.0 doesn't have all that much special. Much have been made of the new kernel patching infrastructure, but realistically, that not only wasn't the reason for the version number change, we've had much bigger changes in other versions. So this is very much a 'solid code progress' release." Beyond the (incomplete) live-patching mechanism, this release includes the removal of the remap_file_pages() system call, improved persistent memory support, the lazytime mount option, and the kernel address sanitizer.

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Posted Apr 13, 2015 23:20 UTC (Mon) by rusty (subscriber, #26) [Link]

Virtio 1.0 standard support. This is cleaned up virtio as specified by OASIS. Transition will generally take years, but this is actually a major milestone, add the first OS to ship 1.0 support.

The 4.0 kernel has been released

Posted Apr 14, 2015 6:43 UTC (Tue) by Lekensteyn (subscriber, #99903) [Link]

Be sure to set the CONFIG_VIRTIO_PCI_LEGACY=y option or all virtio PCI devices (blk, net, etc.) in current QEMU versions will fail to get recognized.

While this is the default, it somehow went wrong in the initial Arch Linux' 4.0-1 testing kernel. See https://bugs.archlinux.org/task/44573 (ignore my force_legacy comment, while there is no VirtIO 1.0 implementation in QEMU stable (2.3.x), the virtio-pci module will fall back to the functioning legacy code path if the modern path detects a legacy device.)

The 4.0 kernel has been released

Posted Apr 14, 2015 10:10 UTC (Tue) by rusty (subscriber, #26) [Link]

The help text (which I wrote) on that option is pretty clear!

Quote:So look out into your driveway. Do you have a flying car? If so, you can happily disable this option and virtio will not break. Otherwise, leave it set. Unless you're testing what life will be like in The Future.