Just under a year ago on my old blog I discussed and even demoed the new Linux live kernel patching solutions. I was reviewing these technologies out of my own curiosity as well as HP's Advanced Technology Group having an interest. I think these technologies are great, I am personally more of a fan of the user experience of RedHat's kpatch solution but any solution is a great technical achievement.
Having said this I believe that the use case for this technology is quite narrow. Last time I looked into these technologies only patches that affected the code of functions could be modified. Changing structs and data definitely didn't work and I suspect that changing function declarations was also dangerous. There is also a performance …[Read more]