[PATCH] cciss: unregister from SCSI before tearing down device resources
authorBjorn Helgaas <bjorn.helgaas@hp.com>
Thu, 12 Apr 2007 06:28:43 +0000 (23:28 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Thu, 12 Apr 2007 22:31:42 +0000 (15:31 -0700)
We must unregister from SCSI before we unmap device resources and unhook
the IRQ handler.  Otherwise, SCSI may send us more requests, and we won't
be able to handle them.

I see the following oops during every reboot of my HP DL360:

    ...
    Unmounting local filesystems...done.
    Rebooting... Completed flushing cache on controller 0
    BUG: unable to handle kernel paging request at virtual address f8808040
     printing eip:
    c02dc72b
    *pde = 02120067
    *pte = 00000000
    Oops: 0002 [#1]
    SMP
    Modules linked in:
    CPU:    1
    EIP:    0060:[<c02dc72b>]    Not tainted VLI
    EFLAGS: 00010046   (2.6.21-rc6 #1)
    EIP is at SA5_submit_command+0xb/0x20
    eax: f8808000   ebx: f7a00000   ecx: f79f0000   edx: 37a00000
    esi: f79f0000   edi: 00000000   ebp: 00000000   esp: dd717a44
    ds: 007b   es: 007b   fs: 00d8  gs: 0000  ss: 0068
    Process khelper (pid: 1427, ti=dd716000 task=c2260a70 task.ti=dd716000)
    Stack: c02df2c0 f7a00000 f7a00000 00d41008 c02df691 00000000 00000010 00000002
   00000001 f79f0000 f7fff844 c1398420 00000000 00000000 00001000 230a3020
   69666564 5420656e 50434f49 465f544b 4853554c 44414552 0a312009 66656423
    Call Trace:
     [<c02df2c0>] start_io+0x80/0x120
     [<c02df691>] do_cciss_request+0x331/0x350
     [<c014242a>] mempool_alloc+0x2a/0xe0
     [<c020ad71>] blk_alloc_request+0x61/0x80
     [<c020b02e>] get_request+0x15e/0x1e0
     [<c01595e0>] cache_alloc_refill+0xb0/0x1e0
     [<c021049d>] as_update_rq+0x2d/0x80
     [<c0210d28>] as_add_request+0x68/0x90
     [<c0207f99>] elv_insert+0x119/0x160
     [<c020bd0b>] __make_request+0xcb/0x320
     [<c0122ee0>] lock_timer_base+0x20/0x50
     [<c0123096>] del_timer+0x56/0x60
     [<c020a7b8>] blk_remove_plug+0x38/0x70
     [<c020a815>] __generic_unplug_device+0x25/0x30
     [<c020a835>] generic_unplug_device+0x15/0x30
    ...

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/block/cciss.c

index 14d780666c0a40257e4c6aa4dbb2a06d460b462c..65a725cd3422ec565d9508de378d32cb9c52ffd5 100644 (file)
@@ -3423,6 +3423,25 @@ static void cciss_remove_one(struct pci_dev *pdev)
                       "already be removed \n");
                return;
        }
+
+       remove_proc_entry(hba[i]->devname, proc_cciss);
+       unregister_blkdev(hba[i]->major, hba[i]->devname);
+
+       /* remove it from the disk list */
+       for (j = 0; j < CISS_MAX_LUN; j++) {
+               struct gendisk *disk = hba[i]->gendisk[j];
+               if (disk) {
+                       request_queue_t *q = disk->queue;
+
+                       if (disk->flags & GENHD_FL_UP)
+                               del_gendisk(disk);
+                       if (q)
+                               blk_cleanup_queue(q);
+               }
+       }
+
+       cciss_unregister_scsi(i);       /* unhook from SCSI subsystem */
+
        /* Turn board interrupts off  and send the flush cache command */
        /* sendcmd will turn off interrupt, and send the flush...
         * To write all data in the battery backed cache to disks */
@@ -3444,22 +3463,6 @@ static void cciss_remove_one(struct pci_dev *pdev)
 #endif                         /* CONFIG_PCI_MSI */
 
        iounmap(hba[i]->vaddr);
-       cciss_unregister_scsi(i);       /* unhook from SCSI subsystem */
-       unregister_blkdev(hba[i]->major, hba[i]->devname);
-       remove_proc_entry(hba[i]->devname, proc_cciss);
-
-       /* remove it from the disk list */
-       for (j = 0; j < CISS_MAX_LUN; j++) {
-               struct gendisk *disk = hba[i]->gendisk[j];
-               if (disk) {
-                       request_queue_t *q = disk->queue;
-
-                       if (disk->flags & GENHD_FL_UP)
-                               del_gendisk(disk);
-                       if (q)
-                               blk_cleanup_queue(q);
-               }
-       }
 
        pci_free_consistent(hba[i]->pdev, hba[i]->nr_cmds * sizeof(CommandList_struct),
                            hba[i]->cmd_pool, hba[i]->cmd_pool_dhandle);