When the canary breaks the coal mine
Nobody likes it when kernels don't work and even less so when they are broken on a Friday afternoon. Yet that's what happened last Friday. This was particularly unsettling because at -rc8, the kernel...
View ArticleDevConf 2018
DevConf 2018 happened. A grand time was had by me (and hopefully others) Robbie Harwood gave an overview of Kerberos for Developers. Kerberos has a reputation for being difficult to use and manage. As...
View ArticleFun with gcc plugins
One of piece of infrastructure that's come in as part of the Kernel Self Protection Project (KSPP) is support for gcc plugins. I touched on this briefly in my DevConf talk but I wanted to discuss a few...
View ArticleKbuild tricks
Several of the tasks I've worked on recently have involved looking at some of the kernel's build infrastructure. This is all fairly well documented which makes it nice to work with. The kernel...
View ArticleLSF/MM 2018
Wheee LSF/MM. Highlights. There were a couple of sessions related to everyone's favorite mitigation, PTI. Unsurprisingly, PTI has an impact on I/O heavy workloads because it makes system calls more...
View ArticleSome notes on recent random numbers
By now people may have seen complaints of boot slowdown on newer kernels. I want to explain a little more about what's going on and why Fedora seems to be particularly hard hit. The Linux kernel has a...
View ArticleFantastic kernel patches and where to find them
I've griped before about kernel development being scattered and spread about. A quick grep of MAINTAINERS shows over 200 git trees and even more mailing lists. Today's discussion is a partial...
View ArticleMore kbuild for reproducible builds
I'm still working on patches to deal with build ids for the kernel. One issue I spent way too long figuring out was that if you just do a basic make for the kernel, some local environment information...
View ArticleWhat's a kernel devel package anyway
One of the first concepts you learn when building open source software is the existance of -devel packages. You have package foo to provide some functionality and foo-devel for building other programs...
View ArticleThe cabbage patch for linker scripts
Quick quiz: what package provides ld? If you said binutils and not gcc, you are a winner! That's not actually the story, I just tend to forget which package to look at when digging into problems. This...
View ArticleFlock 2018
Last week was Flock 2018. Highlights: I gave a talk on the relationship between the Fedora and RHEL kernels. The short summary is that that the two kernels are not closely related, despite the fact...
View ArticleKernel community management
I was at Open Source Summit last week (full trip report forthcoming) and like always one of the keynotes was Linus being interviewed by Dirk Hohndel. The topic of the kernel community and community...
View ArticleLSS/OSS NA 2018
Last week was Open Source Summit and Linux Security Summit in beautiful Vancouver, BC. Highlights: There was a talk on security in Zephyr and Fuchsia. While the focus of the conference is Linux,...
View ArticleString copying in the kernel
One of the many areas that the kernel self protection project looks at is making sure kernel developers are using APIs correctly and safely. The string APIs, in particular string copying APIs, seem to...
View ArticleKconfig symbol visibility
I managed to get bit by the same issue twice in about 24 hours so I guess it's time for a blog post. If you've ever compiled a kernel, you have dealt with kconfig symbols (CONFIG_FOO) which are used to...
View ArticleKernel numbering and Fedora
By now it's made the news that the kernel version has jumped to version 5.0. Once again, this numbering jump means nothing except Linus decide that he wanted to change it. We've been through versioning...
View ArticleService on the TAB
I never posted about it but I was elected to the TAB last November. I'm deeply appreciative towards several people who reached out and encouraged me to run. I probably wouldn't have run if they hadn't...
View ArticlePetty gripes about kernel versioning and tarballs
Today in gripes that about 5 people including me will have: it's really difficult to find a unified way to get a tarball from something on kernel.org to the Fedora dist-git in a way that meets the...
View ArticleWhy you can't (easily) get Kconfig help from the command line
When something seemingly simple isn't implemented in an open source project, there are two likely reasons. One, nobody has bothered to sit down and work on it because it's so simple. Two, it's not...
View ArticleWhat's a kernel headers package anyway
I've written before about what goes into Fedora's kernel-devel package. Briefly, it consists of files that come out of the kernel's build process that are needed to build kernel modules. In contrast to...
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