On Tue, Sep 15, 2015 at 9:39 AM, Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> wrote: > On Mon, Sep 14, 2015 at 7:54 PM, Olga Kornievskaia <aglo@xxxxxxxxx> wrote: >> A test case is as the description says: >> open(foobar, O_WRONLY); >> sleep() --> reboot the server >> close(foobar) >> >> The bug is because in nfs4state.c in nfs4_reclaim_open_state() a few >> line before going to restart, there is >> clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &state->flags). >> >> NFS4CLNT_RECLAIM_NOGRACE is a flag for the client states not open >> owner states. Value of NFS4CLNT_RECLAIM_NOGRACE is 4 which is the >> value of NFS_O_WRONLY_STATE in nfs4_state->flags. So clearing it wipes >> out state and when we go to close it, “call_close” doesn’t get set as >> state flag is not set and CLOSE doesn’t go on the wire. >> >> That line was introduced to fix an infinite loop for OPEN recovery >> upon receiving a BAD_STATEID error: commit e8d975e73. I have tested >> injecting BAD_STATEID error using the patch below and the code >> recovers without problems. However, I'm not sure the clearing of the >> bit is needed any more. I have tested for infinite loop by reverting >> the patch and didn't hit the infinite loop. >> >> diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c >> index da73bc4..5db3246 100644 >> --- a/fs/nfs/nfs4state.c >> +++ b/fs/nfs/nfs4state.c >> @@ -1481,7 +1481,7 @@ restart: >> spin_unlock(&state->state_lock); >> } >> nfs4_put_open_state(state); >> - clear_bit(NFS4CLNT_RECLAIM_NOGRACE, >> + clear_bit(NFS_STATE_RECLAIM_NOGRACE, >> &state->flags); >> spin_lock(&sp->so_lock); >> goto restart; > > That's an obvious typo. Thanks for spotting it! > > As for whether or not the bit clear is needed at all, I think it is > for NFSv4 on older kernels. On newer kernels, we do have the NFSv4 > state recovery drain the slot table (just like we've always done for > NFSv4.1) and so I agree that those kernels probably won't be > afflicted. > Thanks Trond. Do you need me to resubmit it without the last paragraph or is the patch ok as is? > Cheers > Trond -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
