On 19 Jun 2015, at 10:36, Emmanuel Dreyfus <m...@netbsd.org> wrote:
> Hi
>
> I have encountered a bug with NetBSD NFS client. Despite a mount with
> -o intr,soft, we can hit situation where a process can remain hang in
> kernel because the NFS server is gone.
>
> This happens when the ioflush does its duty, with the following code path:
> sync_fsync / nfs_sync / VOP_FSYNC / nfs_fsync / nfs_flush / VOP_PUTPAGES
>
> VOP_PUTPAGES has flags = PGO_ALLPAGES|PGO_FREE. It then goes through
> genfs_putpages and genfs_do_putpages, and get stuck in:
>
> /* Wait for output to complete. */
> if (!wasclean && !async && vp->v_numoutput != 0) {
> while (vp->v_numoutput != 0)
> cv_wait(&vp->v_cv, slock);
> }
Looks like your problem is the missing nfs aware implementation of
function nfs_node.c:nfs_gop_write(). Falling back to genfs_gop_write()
ignores nfs timeouts.
--
J. Hannken-Illjes - hann...@eis.cs.tu-bs.de - TU Braunschweig (Germany)
