Commit 65110b21 authored by James Bottomley's avatar James Bottomley Committed by
Browse files

[SCSI] fix wrong context bugs in SCSI 



There's a bug in releasing scsi_device where the release function
actually frees the block queue.  However, the block queue release
calls flush_work(), which requires process context (the scsi_device
structure may release from irq context).  Update the release function
to invoke via the execute_in_process_context() API.

Also clean up the scsi_target structure releasing via this API.

Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent faead26d

drivers/scsi/scsi_scan.c

+4 −22
Original line number Diff line number Diff line
@@ -387,19 +387,12 @@ static struct scsi_target *scsi_alloc_target(struct device *parent, 
	return found_target;

}



struct work_queue_wrapper {

	struct work_struct	work;

	struct scsi_target	*starget;

};



static void scsi_target_reap_work(void *data) {

	struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;

	struct scsi_target *starget = wqw->starget;

static void scsi_target_reap_usercontext(void *data)

{

	struct scsi_target *starget = data;

	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);

	unsigned long flags;



	kfree(wqw);



	spin_lock_irqsave(shost->host_lock, flags);



	if (--starget->reap_ref == 0 && list_empty(&starget->devices)) {
@@ -428,18 +421,7 @@ static void scsi_target_reap_work(void *data) { 
 */

void scsi_target_reap(struct scsi_target *starget)

{

	struct work_queue_wrapper *wqw = 

		kzalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);



	if (!wqw) {

		starget_printk(KERN_ERR, starget,

			       "Failed to allocate memory in scsi_reap_target()\n");

		return;

	}



	INIT_WORK(&wqw->work, scsi_target_reap_work, wqw);

	wqw->starget = starget;

	schedule_work(&wqw->work);

	scsi_execute_in_process_context(scsi_target_reap_usercontext, starget);

}



/**

drivers/scsi/scsi_sysfs.c

+8 −1
Original line number Diff line number Diff line
@@ -217,8 +217,9 @@ static void scsi_device_cls_release(struct class_device *class_dev) 
	put_device(&sdev->sdev_gendev);

}



static void scsi_device_dev_release(struct device *dev)

static void scsi_device_dev_release_usercontext(void *data)

{

	struct device *dev = data;

	struct scsi_device *sdev;

	struct device *parent;

	struct scsi_target *starget;
@@ -237,6 +238,7 @@ static void scsi_device_dev_release(struct device *dev) 


	if (sdev->request_queue) {

		sdev->request_queue->queuedata = NULL;

		/* user context needed to free queue */

		scsi_free_queue(sdev->request_queue);

		/* temporary expedient, try to catch use of queue lock

		 * after free of sdev */
@@ -252,6 +254,11 @@ static void scsi_device_dev_release(struct device *dev) 
		put_device(parent);

}



static void scsi_device_dev_release(struct device *dev)

{

	scsi_execute_in_process_context(scsi_device_dev_release_usercontext,	dev);

}



static struct class sdev_class = {

	.name		= "scsi_device",

	.release	= scsi_device_cls_release,

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