Commit:     031fd3aa20fcf6d1862ea7814ee8b2caf36c0d78
Parent:     551e4fb2465b87de9d4aa1669b27d624435443bb
Author:     Jeff Layton <[EMAIL PROTECTED]>
AuthorDate: Wed Feb 6 11:34:10 2008 -0500
Committer:  J. Bruce Fields <[EMAIL PROTECTED]>
CommitDate: Sun Feb 10 18:09:36 2008 -0500

    It's currently possible for an unresponsive NLM client to completely
    lock up a server's lockd. The scenario is something like this:
    1) client1 (or a process on the server) takes a lock on a file
    2) client2 tries to take a blocking lock on the same file and
       awaits the callback
    3) client2 goes unresponsive (plug pulled, network partition, etc)
    4) client1 releases the lock that point the server's lockd will try to queue up a GRANT_MSG
    callback for client2, but first it requeues the block with a timeout of
    30s. nlm_async_call will attempt to bind the RPC client to client2 and
    will call rpc_ping. rpc_ping entails a sync RPC call and if client2 is
    unresponsive it will take around 60s for that to time out. Once it times
    out, it's already time to retry the block and the whole process repeats.
    Once in this situation, nlmsvc_retry_blocked will never return until
    the host starts responding again. lockd won't service new calls.
    Fix this by skipping the RPC ping on NLM RPC clients. This makes
    nlm_async_call return quickly when called.
    Signed-off-by: Jeff Layton <[EMAIL PROTECTED]>
    Signed-off-by: J. Bruce Fields <[EMAIL PROTECTED]>
 fs/lockd/host.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index ca6b16f..00063ee 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -244,6 +244,7 @@ nlm_bind_host(struct nlm_host *host)
                        .version        = host->h_version,
                        .authflavor     = RPC_AUTH_UNIX,
                        .flags          = (RPC_CLNT_CREATE_HARDRTRY |
+                                          RPC_CLNT_CREATE_NOPING |
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