On 10/8/23 8:38 PM, Dan Clash wrote: > I retested with the following change as a sanity check: > > - BUG_ON(name->refcnt <= 0); > + BUG_ON(atomic_read(&name->refcnt) <= 0); > > checkpatch.pl suggests using WARN_ON_ONCE rather than BUG. > > devvm ~ $ ~/linux/scripts/checkpatch.pl --patch ~/io_uring_audit_hang_atomic.patch > WARNING: Do not crash the kernel unless it is absolutely unavoidable > --use WARN_ON_ONCE() plus recovery code (if feasible) instead of BUG() or variants > #28: FILE: fs/namei.c:262: > + BUG_ON(atomic_read(&name->refcnt) <= 0); > ... > > refcount_t uses WARN_ON_ONCE. > > I can think of three choices: > > 1. Use atomic_t and remove the BUG line. > 2. Use refcount_t and remove the BUG line. > 3. Use atomic_t and partially implement the warn behavior of refcount_t. > > Choice 1 and 2 seem better than choice 3. I'd probably just make it: if (WARN_ON_ONCE(!atomic_read(name->refcnt))) return; to make it a straightforward conversion. -- Jens Axboe
