[PATCH] libata: fix oops caused rescanning NULL sdev

Depending on timing, ata_scsi_dev_rescan() might encounter a device
which is enabled but not yet attached to sdev.  On such cases, the
original code caused oops.  This patch makes ata_scsi_dev_rescan()
rescan only device which are attached to sdevs.

While at it, properly indent leading comment and add description about
how it's synchronized with sdev attach/detach.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This commit is contained in:
Tejun Heo 2006-06-12 22:51:14 +09:00 committed by Jeff Garzik
parent d4c85325a8
commit d01712698c

View file

@ -3005,14 +3005,16 @@ static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
}
/**
* ata_scsi_dev_rescan - initiate scsi_rescan_device()
* @data: Pointer to ATA port to perform scsi_rescan_device()
* ata_scsi_dev_rescan - initiate scsi_rescan_device()
* @data: Pointer to ATA port to perform scsi_rescan_device()
*
* After ATA pass thru (SAT) commands are executed successfully,
* libata need to propagate the changes to SCSI layer.
* After ATA pass thru (SAT) commands are executed successfully,
* libata need to propagate the changes to SCSI layer. This
* function must be executed from ata_aux_wq such that sdev
* attach/detach don't race with rescan.
*
* LOCKING:
* Kernel thread context (may sleep).
* LOCKING:
* Kernel thread context (may sleep).
*/
void ata_scsi_dev_rescan(void *data)
{
@ -3023,8 +3025,7 @@ void ata_scsi_dev_rescan(void *data)
for (i = 0; i < ATA_MAX_DEVICES; i++) {
dev = &ap->device[i];
if (ata_dev_enabled(dev))
if (ata_dev_enabled(dev) && dev->sdev)
scsi_rescan_device(&(dev->sdev->sdev_gendev));
}
}