scsi: fix device handler detach oops

This fixes a regression caused by commit 1d5203 ("scsi: handle more device
handler setup/teardown in common code").

The bug is that the alua detach() callout will try to access the
sddev->scsi_dh_data, but we have already set it to NULL. This patch
moves the clearing of that field to after detach() is called.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c
index 1dba62c5cf6a0b364df79805f5e8ee857ba36b46..1efebc9eedfb384312de87e0bd4548599524b0dc 100644 (file)
--- a/drivers/scsi/device_handler/scsi_dh.c
+++ b/drivers/scsi/device_handler/scsi_dh.c
@@ -136,11 +136,12 @@ static void __detach_handler (struct kref *kref)
        struct scsi_device_handler *scsi_dh = scsi_dh_data->scsi_dh;
        struct scsi_device *sdev = scsi_dh_data->sdev;
 
+       scsi_dh->detach(sdev);
+
        spin_lock_irq(sdev->request_queue->queue_lock);
        sdev->scsi_dh_data = NULL;
        spin_unlock_irq(sdev->request_queue->queue_lock);
 
-       scsi_dh->detach(sdev);
        sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", scsi_dh->name);
        module_put(scsi_dh->module);
 }