Messages in this thread |  | | Date | Fri, 15 Apr 2022 21:49:51 -0700 | Subject | Re: [PATCH v4 1/1] scsi: Fix racing between dev init and dev reset | From | Bart Van Assche <> |
| |
On 4/14/22 23:12, Alice Chao wrote: > diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c > index 0a70aa763a96..abf9a71ed77c 100644 > --- a/drivers/scsi/scsi_lib.c > +++ b/drivers/scsi/scsi_lib.c > @@ -2461,6 +2461,7 @@ static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt) > break; > case SDEV_EVT_POWER_ON_RESET_OCCURRED: > envp[idx++] = "SDEV_UA=POWER_ON_RESET_OCCURRED"; > + wait_event(sdev->host->host_wait, sdev->sdev_gendev.kobj.parent != NULL); > break; > default: > /* do nothing */ > diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c > index f4e6c68ac99e..431f229ac435 100644 > --- a/drivers/scsi/scsi_scan.c > +++ b/drivers/scsi/scsi_scan.c > @@ -1904,6 +1904,7 @@ static void do_scsi_scan_host(struct Scsi_Host *shost) > } else { > scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, > SCAN_WILD_CARD, 0); > + wake_up(&shost->host_wait); > } > }
The above patch can only work if scanning a host is followed by a POWER ON unit attention. I don't think that is guaranteed. Additionally, what will happen with the wait loop if the device generates a POWER on unit attention after the device has been removed from its parent? kobject_del() clears the parent pointer. device_del() calls kobject_del(). scsi_remove_device() calls device_del() before the request queue is destroyed.
Thanks,
Bart.
|  |