[PATCH 03/23] nvmet: add context annotation for nvmet_ns::file

[Bart Van Assche]

On 11/8/26 7:28 PM, Nilay Shroff wrote:
 > @@ -258,6 +258,19 @@ static void nvmet_file_flush_work(struct 
work_struct *w)
 >  {
 >  	struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
 >
 > +	/*
 > +	 * The flush work is scheduled from the I/O hotpath after acquiring
 > +	 * a reference to the namespace. This ensures that the namespace
 > +	 * cannot be modified while the I/O is in flight.
 > +	 *
 > +	 * nvmet_file_flush() requires callers to hold ns->subsys->lock.
 > +	 * Since we already hold a namespace reference, explicitly assert
 > +	 * the lock capability here to satisfy the context analyzer.
 > +	 *
 > +	 * Other callers of nvmet_file_flush() that do not hold a namespace
 > +	 * reference must acquire ns->subsys->lock before invoking it.
 > +	 */
 > +	__assume_ctx_lock(&req->ns->subsys->lock);
 >  	nvmet_req_complete(req, nvmet_file_flush(req));
 >  }

This assertion is incorrect. __assume_ctx_lock() informs the compiler
that a capability is held when it is actually held (e.g. through an alias).
Here, nvmet_file_flush_work() runs in a workqueue without holding
subsys->lock. If lockdep_assert_held() were used here, Lockdep would
trigger a warning.

nvmet_file_flush() should not be annotated with 
__must_hold(&req->ns->subsys->lock).

Thanks,

Bart.