On Wed, Feb 04, 2026 at 11:45:17PM -0500, Waiman Long wrote: > @@ -70,6 +74,8 @@ void chroot_fs_refs(const struct path *old_root, const > struct> > count++; > path_get(new_root); > } > + count += fs->pwd_xrefs; > + fs->pwd_xrefs = 0; > write_sequnlock(&fs->seq);
Nope - you only need that for threads that have ->pwd equal to old_root. Incidentally, I'd forgotten about that sucker - it kills the idea of fdget-like tricks dead, more's the pity. Third-party modification of task->fs->pwd (under task->lock and task->fs->seq), possible even with task->fs->users == 1. FWIW, I'm going through the fs_struct uses at the moment; will post whatever I get when I go down (or earlier, in the unlikely case it doesn't spill to tomorrow morning), will keep posting incremental followups until the documentation is done. I'm sick and tired of half-finished docs - let's see if I can push through that one this way ;-/
