openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

scsi: Skip deleted devices in __scsi_device_lookup 

When a device is unplugged from a SCSI controller, if the scsi_device is
still in use by application layer, it won't get released until users
close it.

In this case, scsi_device_remove just set the scsi_device's state to be
SDEV_DEL. But if you plug the disk just before the old scsi_device is
released, then there will be two scsi_device structures in
scsi_host->__devices. When the next unplug event happens, some low-level
drivers will check whether the scsi_device has been added to host (for
example the MegaRAID SAS series controller) by calling
scsi_device_lookup(call __scsi_device_lookup) in function
megasas_aen_polling. __scsi_device_lookup will return the first
scsi_device. Because its state is SDEV_DEL, the scsi_device_lookup will
return NULL, making the low-level driver assume that the scsi_device has
been removed, and won't call scsi_device_remove which will lead to hot
swap failure.

Signed-off-by: Zhou Zhengping <johnzzpcrystal@gmail.com>
Tested-by: Zeng Rujia <ZengRujia@sangfor.com.cn>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195607
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Zhou Zhengping 2017-04-28 17:43:04 +08:00 committed by Martin K. Petersen
parent 4492b739c9
commit 4ff7adc8c7
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/scsi/scsi.c
View File

@ -763,6 +763,8 @@ struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost,
struct scsi_device *sdev;
list_for_each_entry(sdev, &shost->__devices, siblings) {
if (sdev->sdev_state == SDEV_DEL)
continue;
if (sdev->channel == channel && sdev->id == id &&
sdev->lun ==lun)
return sdev;