KERNEL WATCH
Jon Masters summarises the latest happenings in the Linux kernel, so that you don’t have to.
Linus Torvalds has announced several Release Candidate (RC) kernels for what will become 5.14 by the time you read this. The 5.14-rc4 kernel (and later) include an important fix to the handling of pipes that’s required to properly fix a regression that had affected Android.
The regression occurred because applications were assuming certain semantic behaviour not part of the specification, but instead part of the existing implementation. In such cases, Linux will always aim not to break userspace at almost all costs, even if applications are using an interface incorrectly. The only time this isn’t true is when a breakage is so isolated that it’s known not to impact anyone, or when a security vulnerability necessitates some kind of unavoidable impact upon userspace. This is why Linus regularly asks developers to test his RC releases. He wants to know about this kind of breakage in time to fix it before it goes into lots of Linux distributions.