OK, now I pushed the fix for the original workqueue warning to kernel SLE15 branch, which will be merged to openSUSE-15.1 branch later. The remaining issue, the blockage at lshw or hwinfo seems irrelevant with the workqueue problem. When this happens, do you have any control on the machine, e.g. you can still operate GUI? Or is it a hard-freeze (e.g. the LED blinking)?