[bug report] lightnvm: pblk: return NVM_ error on failed submission

[Dan Carpenter <dan.carpenter@oracle.com>]

Hello Javier González,

The patch b6730dd4a954: "lightnvm: pblk: return NVM_ error on failed
submission" from Jun 1, 2018, leads to the following static checker
warning:

	drivers/lightnvm/pblk-recovery.c:473 pblk_recov_scan_oob()
	warn: 'pblk->inflight_io.counter' not decremented on lines: 426.

drivers/lightnvm/pblk-recovery.c
   417  
   418                  for (j = 0; j < pblk->min_write_pgs; j++, i++)
   419                          ppa_list[i] =
   420                                  addr_to_gen_ppa(pblk, paddr + j, line->id);
   421          }
   422  
   423          ret = pblk_submit_io_sync(pblk, rqd, data);
   424          if (ret) {
   425                  pblk_err(pblk, "I/O submission failed: %d\n", ret);
   426                  return ret;

The pblk_submit_io_sync() increments the pblk->inflight_io counter but
doesn't decrement it on all error paths.  It looks like something a
little bit subtle is going no but I'm not sure how it works exactly.

   427          }
   428  
   429          atomic_dec(&pblk->inflight_io);
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

   430  
   431          /* If a read fails, do a best effort by padding the line and retrying */
   432          if (rqd->error && rqd->error != NVM_RSP_WARN_HIGHECC) {
   433                  int pad_distance, ret;
   434  
   435                  if (padded) {
   436                          pblk_log_read_err(pblk, rqd);
   437                          return -EINTR;
   438                  }
   439  

regards,
dan carpenter