Comment 6 for bug 77734

I've slightly modified the trace-code to try and report the name of the callback function in the block I/O request (struct request.end_io) but unfortunately its null.

Any suggestions on how to find out what process/function put the job in the queue, hopefully without logging *every* job added, would be useful.

The trace shows:

Trace: hde attempting to read sector address 135202804
Trace: Call back function address end_io 00000000
Trace: Call back function name 0x0<7>Trace: Trying to force a stack trace
 [<c010482d>] show_trace+0xd/0x10
 [<c0104ed7>] dump_stack+0x17/0x20
 [<f882cab4>] ide_do_rw_disk+0x1c4/0x690 [ide_disk]
 [<c02504a7>] ide_do_request+0x6c7/0x8c0
 [<c02509b9>] do_ide_request+0x19/0x20
 [<c01ddcbc>] cfq_kick_queue+0x5c/0xc0
 [<c0132652>] run_workqueue+0x72/0xf0
 [<c0133288>] worker_thread+0x118/0x140
 [<c0135fd7>] kthread+0xa7/0xd0
 [<c0101005>] kernel_thread_helper+0x5/0x10
hde: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hde: dma_intr: error=0x04 { DriveStatusError }
ide: failed opcode was: unknown

and the code in drivers/ide/ide-disk.c now reads:

/* report when suspect sector numbers are addressed */
 unsigned int bad_index;
 if ( strcmp(drive->name,"hde") == 0) { /* is it one of the affected drives? */
  /* make it easy to compare the known sector addresses */
  sector_t bad_address[8] = {135202804ULL, 135202808ULL, 135202972ULL, 135202976ULL,
                             135203028ULL, 135203032ULL, 135203036ULL, 135203040ULL };

  /* simple loop to compare current sector request with known bad sector addresses */
  for (bad_index = 0; bad_index < 8; bad_index++) {
   if (block == bad_address[bad_index]) { /* force a stack-trace */
    if (printk_ratelimit()) {
     printk(KERN_DEBUG "Trace: %s attempting to read sector address %lld\n",drive->name, bad_address[bad_index]);
     printk(KERN_DEBUG "Trace: Call back function address end_io %08lx\n",(unsigned long) rq->end_io);
     print_symbol("Trace: Call back function name %s\n", (unsigned long) rq->end_io);
     printk(KERN_DEBUG "Trace: Trying to force a stack trace\n");
     dump_stack();
     break;
    }
   }
  }
 }
/* end of call-trace */