4.20-stable review patch. If anyone has any objections, please let me know.
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From: J. Bruce Fields bfields@redhat.com
commit 3bf6b57ec2ec945e5a6edf5c202a754f1e852ecd upstream.
This reverts commit d6ebf5088f09472c1136cd506bdc27034a6763f8.
I forgot that the kernel's default lease period should never be decreased!
After a kernel upgrade, the kernel has no way of knowing on its own what the previous lease time was. Unless userspace tells it otherwise, it will assume the previous lease period was the same.
So if we decrease this value in a kernel upgrade, we end up enforcing a grace period that's too short, and clients will fail to reclaim state in time. Symptoms may include EIO and log messages like "NFS: nfs4_reclaim_open_state: Lock reclaim failed!"
There was no real justification for the lease period decrease anyway.
Reported-by: Donald Buczek buczek@molgen.mpg.de Fixes: d6ebf5088f09 "nfsd4: return default lease period" Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields bfields@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/nfsd/nfsctl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1239,8 +1239,8 @@ static __net_init int nfsd_init_net(stru retval = nfsd_idmap_init(net); if (retval) goto out_idmap_error; - nn->nfsd4_lease = 45; /* default lease time */ - nn->nfsd4_grace = 45; + nn->nfsd4_lease = 90; /* default lease time */ + nn->nfsd4_grace = 90; nn->somebody_reclaimed = false; nn->clverifier_counter = prandom_u32(); nn->clientid_counter = prandom_u32();