Bug 195607

Summary: Megaraid_sas raidcard hotswap wouldn't work if hold the fd of block devcie in user space
Product: SCSI Drivers Reporter: Zhou Zhengping (johnzzpcrystal)
Component: OtherAssignee: scsi_drivers-other
Status: NEW ---    
Severity: normal    
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 3.10.0 Subsystem:
Regression: No Bisected commit-id:

Description Zhou Zhengping 2017-04-28 08:29:03 UTC 
reproduce :

1.choose a megaraid sas series raidcard, for example:
LSI Logic / Symbios Logic MegaRAID　SAS 2008 [Falcon] (rev 03)

2. configure the raid card as HBA card (all disks are jbod mode)
We assume /dev/sdb is attached to this raid card

3.run process:
fd = open("/dev/sdb", O_RDWR);
while (1) {
    sleep (10);
}

4. run "udevadm monitor" watch udev message in a new shell

5.unplug disk sdb and then insert 

We can see new udev message about disk's hotswap

6.redo process 5
There will be no udev message only if you reboot the server