[SCSI] ipr: Stop reading adapter dump prematurely

When the ipr driver decides to dump the adapter, it changes the
sdt_state to GET_DUMP, then prepares the adapter so that the dump
can be read. However, if the ipr worker thread wakes up for some
reason before the driver has put the adapter in a state where it
can succesfully dump the adapter, the driver will start dumping
the adapter too early, which can potentially trigger a BUG check
in the pci config blocking API. Fix this by adding a new
sdt_state to differentiate between the ipr driver wanting to dump
the adapter in the near future and wanting to dump the adapter now.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 12 insertions, 4 deletions

diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index acbb9241262d..f03963a972fc 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -2901,7 +2901,7 @@ static void ipr_get_ioa_dump(struct ipr_ioa_cfg *ioa_cfg, struct ipr_dump *dump)
 
         spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
 
-        if (ioa_cfg->sdt_state != GET_DUMP) {
+        if (ioa_cfg->sdt_state != READ_DUMP) {
                 spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
                 return;
         }
@@ -3097,7 +3097,7 @@ static void ipr_worker_thread(struct work_struct *work)
         ENTER;
         spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
 
-        if (ioa_cfg->sdt_state == GET_DUMP) {
+        if (ioa_cfg->sdt_state == READ_DUMP) {
                 dump = ioa_cfg->dump;
                 if (!dump) {
                         spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
@@ -7449,6 +7449,8 @@ static int ipr_reset_wait_for_dump(struct ipr_cmnd *ipr_cmd)
         struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;
 
         if (ioa_cfg->sdt_state == GET_DUMP)
+                ioa_cfg->sdt_state = WAIT_FOR_DUMP;
+        else if (ioa_cfg->sdt_state == READ_DUMP)
                 ioa_cfg->sdt_state = ABORT_DUMP;
 
         ipr_cmd->job_step = ipr_reset_alert;
@@ -7614,6 +7616,7 @@ static int ipr_reset_restore_cfg_space(struct ipr_cmnd *ipr_cmd)
                 ipr_cmd->job_step = ipr_reset_enable_ioa;
 
                 if (GET_DUMP == ioa_cfg->sdt_state) {
+                        ioa_cfg->sdt_state = READ_DUMP;
                         if (ioa_cfg->sis64)
                                 ipr_reset_start_timer(ipr_cmd, IPR_SIS64_DUMP_TIMEOUT);
                         else
@@ -8003,8 +8006,12 @@ static void ipr_initiate_ioa_reset(struct ipr_ioa_cfg *ioa_cfg,
         if (ioa_cfg->ioa_is_dead)
                 return;
 
-        if (ioa_cfg->in_reset_reload && ioa_cfg->sdt_state == GET_DUMP)
-                ioa_cfg->sdt_state = ABORT_DUMP;
+        if (ioa_cfg->in_reset_reload) {
+                if (ioa_cfg->sdt_state == GET_DUMP)
+                        ioa_cfg->sdt_state = WAIT_FOR_DUMP;
+                else if (ioa_cfg->sdt_state == READ_DUMP)
+                        ioa_cfg->sdt_state = ABORT_DUMP;
+        }
 
         if (ioa_cfg->reset_retries++ >= IPR_NUM_RESET_RELOAD_RETRIES) {
                 dev_err(&ioa_cfg->pdev->dev,
diff --git a/drivers/scsi/ipr.h b/drivers/scsi/ipr.h
index f93f8637c5a1..f9766f84d91c 100644
--- a/drivers/scsi/ipr.h
+++ b/drivers/scsi/ipr.h
@@ -1360,6 +1360,7 @@ enum ipr_sdt_state {
         INACTIVE,
         WAIT_FOR_DUMP,
         GET_DUMP,
+        READ_DUMP,
         ABORT_DUMP,
         DUMP_OBTAINED
 };