On Tue, Feb 06, 2024 at 11:52:58AM -0800, Calvin Owens wrote: > Hello all, > > A couple times in the past week, my laptop has been wedged by a spinning > cleanup_mnt() task_work from an exiting container runtime (bwrap). > > The first time it reproduced was while writing to dm-crypt on nvme, so I > blew it off as a manifestation of the tasklet corruption. But I hit it > again last night on rc3, which contains commit 0a9bab391e33, so that's > not it. > > I'm sorry to say I have very little to go on. Both times it happened, I > was using Nautilus to browse around in some directories, but I've tried > monkeying around with that and had no luck reproducing it. The spinning > happens late enough in the exit path that /proc/self/ is gutted, so I > don't know what the bwrap container was actually doing. > > The NMI stacktrace and the kconfig I'm running are below. The spinning > task still moves between CPUs. No hung task notifications appear except > for random sync() calls happening afterwards from userspace, which all > block on super_lock() in iterate_supers(). Trying to ptrace the stuck > process hangs also hangs the tracing process forever. > > I rebuilt with lockdep this morning, but haven't seen any splats, and > haven't hit the bug again. > > Please let me know if you see anything specific I can test or try that > might help narrow the problem down. Otherwise, I'll keep working on > finding a reliable reproducer. Check if git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git #fixes helps.
