I forgot to mention that I interrupted one of the earlier "rm <dir>/*" calls with Ctrl-C and, when that didn't react, I did Ctrl-Z a few times and then (on the shell) a "bg" - but that was too late, "rm" had already quit.
But I interrupted only one "rm"; not later ones, and surely not the "rm -rf <dir>"); another "rm -rf <dir>" with 117963 files in there just worked normally right now. Seems that the interrupted unlinkat() call did something unusual?!
