In addition to above/below points, which emphasis more on the functionality testing, hardware certification testing and performance testing the Linux kernel.

A lot a testing actually happen through, actually scripts, static code analysis tools, code reviews etc. which is very efficient in catching bugs, which would otherwise break something in the application.

Sparse – An open-source tool designed to find faults in the Linux kernel.

Coccinelle is another program does matching and transformation engine which provides the language SmPL (Semantic Patch Language) for specifying desired matches and transformations in C code.

checkpatch.pl and other scripts - coding style issues can be found in the file Documentation/CodingStyle in the kernel source tree. The important thing to remember when reading it is not that this style is somehow better than any other style, just that it is consistent. this helps developers easily find and fix coding style issues, the script scripts/checkpatch.pl in the kernel source tree has been developed. This script can point out problems easily, and should always be run by a developer on their changes, instead of having a reviewer waste their time by pointing out problems later on.

In addition to the other answers, this emphasise more on the functionality testing, hardware certification testing and performance testing the Linux kernel.

A lot of testing actually happen through scripts, static code analysis tools, code reviews, etc. which is very efficient in catching bugs, which would otherwise break something in the application.

Sparse – An open-source tool designed to find faults in the Linux kernel.

Coccinelle is another program does matching and transformation engine which provides the language SmPL (Semantic Patch Language) for specifying desired matches and transformations in C code.

checkpatch.pl and other scripts - coding style issues can be found in the file Documentation/CodingStyle in the kernel source tree. The important thing to remember when reading it is not that this style is somehow better than any other style, just that it is consistent. This helps developers easily find and fix coding style issues. The script scripts/checkpatch.pl in the kernel source tree has been developed for it. This script can point out problems easily, and should always be run by a developer on their changes, instead of having a reviewer waste their time by pointing out problems later on.