On Tue, Apr 23, 2019 at 11:22:50AM +0100, Mark Rutland wrote: > On Thu, Apr 11, 2019 at 10:37:51AM -0700, Dhaval Giani wrote: > > Hi Folks, > > > > This is a call for participation for the Linux Testing microconference > > at LPC this year. > > > > For those who were at LPC last year, as the closing panel mentioned, > > testing is probably the next big push needed to improve quality. From > > getting more selftests in, to regression testing to ensure we don't > > break realtime as more of PREEMPT_RT comes in, to more stable distros, > > we need more testing around the kernel. > > > > We have talked about different efforts around testing, such as fuzzing > > (using syzkaller and trinity), automating fuzzing with syzbot, 0day > > testing, test frameworks such as ktests, smatch to find bugs in the > > past. We want to push this discussion further this year and are > > interested in hearing from you what you want to talk about, and where > > kernel testing needs to go next. > > I'd be interested to discuss what we could do with annotations and > compiler instrumentation to make the kernel more amenable to static and > dynamic analysis (and to some extent, documenting implicit > requirements). > > One idea that I'd like to explore in the context of RT is to annotate > function signatures with their required IRQ/preempt context, such that > we could dynamically check whether those requirements were violated > (even if it didn't happen to cause a problem at that point in time), and > static analysis would be able to find some obviously broken usage. I had > some rough ideas of how to do the dynamic part atop/within ftrace. Maybe > there are similar problems elsewhere. > > I know that some clang folk were interested in similar stuff. IIRC Nick > Desaulniers was interested in whether clang's thread safety analysis > tooling could be applied to the kernel (e.g. based on lockdep > annotations).
FWIW, I'd also be interested in discussing these developments. There have been several activities/projects related to such "tooling" (thread safety analysis) recently: I could point out the (brand new) Google Summer of Code "Applying Clang Thread Safety Analyser to Linux Kernel" project [1] and (for the "dynamic analysis" side) the efforts to revive the Kernel Thread sanitizer [2]. I should also mention the efforts to add (support for) "unmarked" accesses and to formalize the notion of "data race" in the memory consistency model [3]. So, again, I'd welcome a discussion on these works/ideas. Thanks, Andrea [1] https://summerofcode.withgoogle.com/projects/#5358212549705728 https://github.com/ClangBuiltLinux/thread-safety-analysis [2] https://github.com/google/ktsan/commits/ktsan [3] https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?h=dev&id=c602b9e58cb9c13f260791dd7da6687e06809923 https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?h=dev&id=3b1fe99c68b5673879a8018a46b23f431e4d4b7a https://lkml.kernel.org/r/pine.lnx.4.44l0.1903191459270.1593-200...@iolanthe.rowland.org
