releases/3.14.49/fixing-infinite-open-loop-in-4.0-stateid-recovery.patch

   1 From e8d975e73e5fa05f983fbf2723120edcf68e0b38 Mon Sep 17 00:00:00 2001
   2 From: Olga Kornievskaia <kolga@netapp.com>
   3 Date: Fri, 15 May 2015 11:45:31 -0400
   4 Subject: fixing infinite OPEN loop in 4.0 stateid recovery
   5
   6 From: Olga Kornievskaia <kolga@netapp.com>
   7
   8 commit e8d975e73e5fa05f983fbf2723120edcf68e0b38 upstream.
   9
  10 Problem: When an operation like WRITE receives a BAD_STATEID, even though
  11 recovery code clears the RECLAIM_NOGRACE recovery flag before recovering
  12 the open state, because of clearing delegation state for the associated
  13 inode, nfs_inode_find_state_and_recover() gets called and it makes the
  14 same state with RECLAIM_NOGRACE flag again. As a results, when we restart
  15 looking over the open states, we end up in the infinite loop instead of
  16 breaking out in the next test of state flags.
  17
  18 Solution: unset the RECLAIM_NOGRACE set because of
  19 calling of nfs_inode_find_state_and_recover() after returning from calling
  20 recover_open() function.
  21
  22 Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
  23 Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
  24 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  25
  26 ---
  27  fs/nfs/nfs4state.c |    2 ++
  28  1 file changed, 2 insertions(+)
  29
  30 --- a/fs/nfs/nfs4state.c
  31 +++ b/fs/nfs/nfs4state.c
  32 @@ -1482,6 +1482,8 @@ restart:
  33                                         spin_unlock(&state->state_lock);
  34                                 }
  35                                 nfs4_put_open_state(state);
  36 +                               clear_bit(NFS4CLNT_RECLAIM_NOGRACE,
  37 +                                       &state->flags);
  38                                 spin_lock(&sp->so_lock);
  39                                 goto restart;
  40                         }