git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From b65cfedf4560af65305bd7b3b9f26c02c6fb3660 Mon Sep 17 00:00:00 2001
   2 From: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
   3 Date: Sat, 29 Jun 2013 03:52:03 +0530
   4 Subject: SCSI: mpt3sas: fix for kernel panic when driver loads with HBA conected to non LUN 0 configured expander
   5
   6 From: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
   7
   8 commit b65cfedf4560af65305bd7b3b9f26c02c6fb3660 upstream.
   9
  10 With some enclosures when LUN 0 is not created but LUN 1 or LUN X is created
  11 then SCSI scan procedure calls target_alloc, slave_alloc call back functions
  12 for LUN 0 and slave_destory() for same LUN 0.
  13
  14 In these kind of cases within slave_destroy, pointer to scsi_target in
  15 _sas_device structure is set to NULL, following which when slave_alloc for LUN
  16 1 is called then starget would not be set properly for this LUN.  So,
  17 scsi_target pointer pointing to NULL value would lead to a crash later in the
  18 discovery procedure.
  19
  20 To solve this issue set the sas_device's scsi_target pointer to scsi_device's
  21 scsi_target if it is NULL earlier in slave_alloc callback function.
  22
  23 Signed-off-by: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
  24 Signed-off-by: James Bottomley <JBottomley@Parallels.com>
  25 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  26
  27 ---
  28  drivers/scsi/mpt3sas/mpt3sas_scsih.c |   14 ++++++++++++++
  29  1 file changed, 14 insertions(+)
  30
  31 --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
  32 +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
  33 @@ -1273,6 +1273,7 @@ _scsih_slave_alloc(struct scsi_device *s
  34         struct MPT3SAS_DEVICE *sas_device_priv_data;
  35         struct scsi_target *starget;
  36         struct _raid_device *raid_device;
  37 +       struct _sas_device *sas_device;
  38         unsigned long flags;
  39
  40         sas_device_priv_data = kzalloc(sizeof(struct scsi_device), GFP_KERNEL);
  41 @@ -1301,6 +1302,19 @@ _scsih_slave_alloc(struct scsi_device *s
  42                 spin_unlock_irqrestore(&ioc->raid_device_lock, flags);
  43         }
  44
  45 +       if (!(sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)) {
  46 +               spin_lock_irqsave(&ioc->sas_device_lock, flags);
  47 +               sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
  48 +                                       sas_target_priv_data->sas_address);
  49 +               if (sas_device && (sas_device->starget == NULL)) {
  50 +                       sdev_printk(KERN_INFO, sdev,
  51 +                       "%s : sas_device->starget set to starget @ %d\n",
  52 +                               __func__, __LINE__);
  53 +                       sas_device->starget = starget;
  54 +               }
  55 +               spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
  56 +       }
  57 +
  58         return 0;
  59  }
  60