On Fri, Sep 12, 2025 at 02:04:58PM +0200, Claudio Jeker wrote:
> On Wed, Sep 10, 2025 at 02:18:03AM +0200, Helg wrote:
> > This patch addresses incompatibilities in the way that FUSE handles
> > terminating a FUSE session.
> > 
>  
> Diff looks generally OK. If this is expected behaviour we should probably
> follow it.
> 
> My question is what happens when you kill the fuse userland process but
> end up with the FS still mounted. Is there a chance that this will lockup
> the machine (similar to unreachable NFS servers)?

Once the fuse device is closed, any operation on the old mount point
will result in ENXIO - Device not configured.

> 
> I assume that the idea is that you can restart the FUSE file system daemon
> without remounting the file system (and keeping dirty buffers accross such
> a restart). Is this correct?

I don't think that's the intended purpose and I don't know of any fuse
file systems that attempts this. One advantage of this approach is that
if the file system daemon crashes, any process that is attempting to
read or write on that mount will fail with ENXIO. With automatic unmounting,
programs don't see that the file system has been unmounted.