[BUG bisected] sysfs: cannot create duplicate filename '/devices/virtual/workqueue/scsi_tmf_1073822488'

From: Paul E. McKenney
Date: Tue Aug 20 2024 - 22:16:07 EST


Hello!

Running rcutorture scenario TREE01 on next-20240820 on a dual-socket x86
system (and for that matter on my laptop) got me this warning during boot:

sysfs: cannot create duplicate filename '/devices/virtual/workqueue/scsi_tmf_1073822488'

The number at the end varies from run to run.

Bisection landed here:

b188c57af2b5 ("workqueue: Split alloc_workqueue into internal function and lockdep init")

My reproducer is to run this at the top of the Linux-kernel file tree:

tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --duration 1m --configs "2*TREE01" --trust-make

Reverting this commit on top of next-20240820 gets me clean runs.

I cannot see how the patch would make this happen, but then again,
I don't know this code at all well.

Thoughts?

Thanx, Paul