Re: [PATCH 2/2] fuse: wait for aborted connection before releasing last fuse_dev

[Joanne Koong]

On Mon, May 18, 2026 at 7:46 AM Bernd Schubert <bernd@xxxxxxxxxxx> wrote:
>
>
>
> On 5/18/26 16:32, Berkant Koc wrote:
> > On Mon, 18 May 2026 11:47:00 +0000, Bernd Schubert <bschubert@xxxxxxx> wrote:
> >> Would it be possible for you to test the attached patch?

The fix looks right to me.

Reviewed-by: Joanne Koong <joannelkoong@xxxxxxxxx>

> >
> > Reproducer and KASAN harness from the PATCH 2/2 series are staged.
> > Two-arm plan: revert vs apply, race-widening debug hunk kept in both
> > arms, 2x50 iterations each against torvalds/master tip, KASAN + lockdep
> > + kmemleak enabled. Results back within the day once the base resolves.
> >
> > Blocker before I build. The patch references ring->chan and chan->conn.
> > On mainline fs/fuse/dev_uring_i.h declares struct fuse_ring with
> > struct fuse_conn *fc at line 110, no chan member; grep fuse_chan
> > across fs/fuse/ returns zero hits. As-is the patch fails to compile
> > with "struct fuse_ring has no member named chan".
> >
> > Is this based on a DDN topic branch that introduces a fuse_chan
> > abstraction not yet upstream? If so, point me at the base tree or
> > branch URL and I will rebase the test against that. If the references
> > were meant to be ring->fc and fc against current mainline, confirm and
> > I will adjust before the run.

Yes, on mainline the references are meant to be ring->fc, eg

diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c
index 5c00fd047c8b..27c417fd9451 100644
--- a/fs/fuse/dev_uring.c
+++ b/fs/fuse/dev_uring.c
@@ -570,6 +570,7 @@ static void fuse_uring_async_stop_queues(struct
work_struct *work)
                                      FUSE_URING_TEARDOWN_INTERVAL);
        } else {
                wake_up_all(&ring->stop_waitq);
+               fuse_conn_put(ring->fc);
        }
 }

@@ -599,6 +600,7 @@ void fuse_uring_stop_queues(struct fuse_ring *ring)

        if (atomic_read(&ring->queue_refs) > 0) {
                ring->teardown_time = jiffies;
+               fuse_conn_get(ring->fc);
                INIT_DELAYED_WORK(&ring->async_teardown_work,
                                  fuse_uring_async_stop_queues);
                schedule_delayed_work(&ring->async_teardown_work,

Thanks,
Joanne

> >
> > Assisted-by: Claude:claude-opus-4-7 berkoc-pipeline
> >
>
> Ah, it is based on Miklos' for-next branch, which is also in linux-next
> (I think). Yeah, we have a bit back port headache here.
>
>
> Thanks,
> Bernd