Patches were posted on Monday for Kernel Stack Watch, a new lightweight debugging tool for detecting kernel stack corruption in real-time on Linux.
Jinchao Wang announced the creation of Kernel Stack Watch (kstackwatch) as this new debugging tool for uncovering kernel stack corruption. He summed up nicely with yesterday’s patches:
“This patch series introduces Kernel Stack Watch (KSW), a lightweight debugging tool for detecting kernel stack corruption in real-time. The motivation comes from cases where corruption happens silently in one function but only manifests later as a crash in another, with no direct call trace connection. Such problems are often very difficult to debug with existing tools.
KSW works by combining hardware breakpoints with kprobes/kretprobes. It can watch a stack canary or a selected local variable, and detect the moment the corruption actually occurs. This allows developers to pinpoint the real source, rather than only observing the final crash.
Key features include:
– Lightweight design with minimal impact on bug reproducibility
– Real-time detection of stack corruption
– Simple configuration through `/proc/kstackwatch`
– Support for recursive functions with configurable nesting depthTo validate the approach, I have also prepared test modules and scripts that simulate corruption scenarios.”
The hope is that these real-time warnings allow action to be taken prior to a crash occurring and more quickly uncovering stability issues with the Linux kernel.
See the LKML patch series for those wanting to learn more about Kernel Stack Watch or trying out this early KSW code.
