arcmsr: Fix possible sleep-in-atomic bugs in arcmsr_queue_command

Commit Message

Jia-Ju Bai Dec. 12, 2017, 1:33 p.m. UTC

From: Jia-Ju Bai <[e-mail]>

The driver may sleep under a spinlock, and the function call paths are:
arcmsr_queue_command(acquire the spinlock)
  arcmsr_queue_command_lck
    arcmsr_handle_virtual_command
      arcmsr_iop_message_xfer
        arcmsr_iop_parking
          arcmsr_stop_adapter_bgrb
            arcmsr_hbaA_stop_bgrb
              arcmsr_hbaA_wait_msgint_ready
                msleep --> may sleep

arcmsr_queue_command(acquire the spinlock)
  arcmsr_queue_command_lck
    arcmsr_handle_virtual_command
      arcmsr_iop_message_xfer
        arcmsr_iop_parking
          arcmsr_stop_adapter_bgrb
            arcmsr_hbaB_stop_bgrb
              arcmsr_hbaB_wait_msgint_ready
                msleep --> may sleep

arcmsr_queue_command(acquire the spinlock)
  arcmsr_queue_command_lck
    arcmsr_handle_virtual_command
      arcmsr_iop_message_xfer
        arcmsr_iop_parking
          arcmsr_stop_adapter_bgrb
            arcmsr_hbaC_stop_bgrb
              arcmsr_hbaC_wait_msgint_ready
                msleep --> may sleep

arcmsr_queue_command(acquire the spinlock)
  arcmsr_queue_command_lck
    arcmsr_handle_virtual_command
      arcmsr_iop_message_xfer
        arcmsr_iop_parking
          arcmsr_stop_adapter_bgrb
            arcmsr_hbaD_stop_bgrb
              arcmsr_hbaD_wait_msgint_ready
                msleep --> may sleep

To fix them, msleep is replaced with mdelay.
These bugs are found by my static analysis tool and my code review.

Signed-off-by: Jia-Ju Bai <[e-mail]>
---
 drivers/scsi/arcmsr/arcmsr_hba.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Patch

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index af032c4..31d94bd 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -347,7 +347,7 @@  static uint8_t arcmsr_hbaA_wait_msgint_ready(struct AdapterControlBlock *acb)
 				&reg->outbound_intstatus);
 			return true;
 		}
-		msleep(10);
+		mdelay(10);
 	} /* max 20 seconds */
 
 	return false;
@@ -367,7 +367,7 @@  static uint8_t arcmsr_hbaB_wait_msgint_ready(struct AdapterControlBlock *acb)
 					reg->drv2iop_doorbell);
 			return true;
 		}
-		msleep(10);
+		mdelay(10);
 	} /* max 20 seconds */
 
 	return false;
@@ -385,7 +385,7 @@  static uint8_t arcmsr_hbaC_wait_msgint_ready(struct AdapterControlBlock *pACB)
 				&phbcmu->outbound_doorbell_clear); /*clear interrupt*/
 			return true;
 		}
-		msleep(10);
+		mdelay(10);
 	} /* max 20 seconds */
 
 	return false;
@@ -403,7 +403,7 @@  static bool arcmsr_hbaD_wait_msgint_ready(struct AdapterControlBlock *pACB)
 				reg->outbound_doorbell);
 			return true;
 		}
-		msleep(10);
+		mdelay(10);
 	} /* max 20 seconds */
 	return false;
 }