The new version of Linux Kernel 4.20 has already been released

Few hours ago and After two months of development, Linus Torvalds announced the new version of Linux Kernel 4.20.

That between the most notable changes in this new version of Kernel 4.20 New features are included, of which various corrections have been added in terms of errors and, above all, support for various devices.

In this new version of the Linux Kernel 14,997 patches were made from 1857 developers to the new version, the patch size was 49MB (changes affected 11,402 files, 686,104 lines of code added, 318945 lines removed).

Approximately 47% of all the changes presented in 4.20 are related to device drivers, approximately 17% of the changes are related to updating specific code for hardware architectures, 14% are related to the network stack, 3% are file systems and 4% are internal kernel subsystems.

What's New in Linux Kernel 4.20?

With this new release, support for the C-SKY processor architecture was added as well as the taprio traffic scheduler, the PSI (pressure blocking information) subsystem, P2P DMA for PCI.

Besides whate added signal processing code refactoring, connection of cache network transmission dissectors in the new XArray structure, combining the amdgpu and amdkfd drivers, increasing the performance of the FUSE subsystem, the ability to filter network packets based on secmark tags, allowing nested virtualization for KVM.

Speck is gone

The controversial Speck recently added with Linux 4.17 in the Kernel encryption algorithm was removed in Linux 4.20.

Since Google deprived the trust of the actually intended Android code. This was not due to technology, as the algorithm was developed by the NSA.

And the standardization of this was denied, as the NSA was unwilling to answer detailed questions about the algorithm.

In addition, virtualization has been enhanced with KVM, which now enables virtual machines through virtualization nested in a virtual machine.

Support is also available for the Raspberry Pi Model 3. In the future, the TCP stack will deliver packets with a new algorithm, which should not only be faster but also more secure.

New protocols

A new "taprio" traffic scheduler was implemented in this kernel, which allows managing the sending of packets according to the previously generated time series.

The scheduling method is defined in the IEEE 802.1Qbv specification, takes into account the requirements for transmitting time-sensitive traffic for packet delivery (for example, video and audio streams), and uses different time slots for different classes of traffic.

For the rtnetlink protocol, a strict checking mode is implemented ("Hard check"), which ensures that the relevant information is transmitted to the user space corresponding to the incoming request;

Added the ability to filter dumps with routing information by the protocols used (for example, to separate routes from different routing daemons), types of routes (for example, to assign unicast)

The ID of the routing table and the closest gateway (nexthop).

Such filters have long been supported in iproute2, but were implemented in user space. Moving filters to kernel space allows you to increase the efficiency of large Linux-based routing systems.

In the implementation of network bridges (bridging subsystem), the ability to view VLAN statistics in the context of individual ports has been added;

Support for 5 and 6 channels for the 60 GHz band has been added to the ieee80211 wireless stack, as well as the ability to enable FTM Responder functionality from user space.

And the Kernel 5.0 for when?

Finally, many expected that the new kernel would be analogous to the change to 4.0 since after 4.19 version 5.0 is now expected.

However, since Torvalds does not want to be fixed in a scheme, it was said that Linux 5.0 will come in 2019. Although an estimated date is not known, since at the moment the plans for the next version continue for version 4.21.