On Thu, 2021-06-03 at 11:02 +0100, Richard Purdie wrote: > We're seeing intermittent rcu stalls in qemu system mode emulation which is > causing CI issues for us (Yocto Project). We're struggling to understand > the cause and have tried several things to mitigate without much success. > The stalls are odd in that the log messages look incomplete. An example > from last night:
To answer my own question, the issue is a kernel bug in RCU stall handling. The fix: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?h=rcu/next&id=c583bcb8f5ed and patch which introduced the problem: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?h=rcu/next&id=c583bcb8f5ed Cheers, Richard
