s390 boot woe due to "block: fix busy device checking in blk_drop_partitions"

[Qian Cai]

Reverted the linux-next commit on todayâs tree,

d3ef5536274f (âblock: fix busy device checking in blk_drop_partitionsâ)

makes IBM partition to be recognized again on s390 rootfs,

01: [   83.443963]  dasda:VOL1/  0X0121: dasda1                                 
01: [   85.124667] qeth 0.0.8000 enc8000: renamed from eth0                     
01: [   85.731860] dasd-eckd 0.0.0120: DASD with 4 KB/block, 72122400 KB total s
01: ize, 48 KB/track, compatible disk layout                                    
01: [   86.076722]  dasdb:VOL1/  0X0120: dasdb1 dasdb2

Otherwise, it is DOA,

00:          Starting Show Plymouth Boot Screen...                              
00: [   37.202263] qeth 0.0.8000: portname is deprecated and is ignored         
00: [   37.677993] qdio: 0.0.8002 OSA on SC 4 using AI:1 QEBSM:0 PRI:1 TDD:1 SIG
00: A:RW A                                                                      
00: [   37.770970] qeth 0.0.8000: MAC address 02:de:ad:be:ef:87 successfully reg
00: istered                                                                     
00: [   37.771547] qeth 0.0.8000: Device is a Virtual NIC QDIO card (level: V642
00: )                                                                           
00: [   37.771547] with link type Virt.NIC QDIO.                                
00: [   38.036231] ccw_init (415) used greatest stack depth: 56496 bytes left   
00:          Starting dracut initqueue hook...                                  
00: [   39.176304] dasd-eckd 0.0.0120: A channel path to the device has become o
00: perational                                                                  
00: [   39.453273] dasd-eckd 0.0.0120: New DASD 3390/0E (CU 3990/01) with 100170
00:  cylinders, 15 heads, 224 sectors                                           
00: [   39.655564] dasd-eckd 0.0.0121: A channel path to the device has become o
00: perational                                                                  
00: [   39.722706] dasd-eckd 0.0.0121: New DASD 3390/0E (CU 3990/01) with 100170
00:  cylinders, 15 heads, 224 sectors                                           
01: [   41.133963] dasd-eckd 0.0.0121: DASD with 4 KB/block, 72122400 KB total s
01: ize, 48 KB/track, compatible disk layout                                    
01: [   41.145510] dasd-eckd 0.0.0120: DASD with 4 KB/block, 72122400 KB total s
01: ize, 48 KB/track, compatible disk layout                                    
01: [   41.609625] qeth 0.0.8000 enc8000: renamed from eth0  
01: [   41.609625] qeth 0.0.8000 enc8000: renamed from eth0                     
01: Warning: /dev/mapper/rhel_ibm--z--135-root does not exist                   
01: Warning: /dev/rhel_ibm-z-135/root does not exist                            
01: Warning: /dev/rhel_ibm-z-135/swap does not exist                            
01:                                                                             
01: Generating "/run/initramfs/rdsosreport.txt"                                 
01:                                                                             
01:                                                                             
01: Entering emergency mode. Exit the shell to continue.                        
01: Type "journalctl" to view system logs.                                      
01: You might want to save "/run/initramfs/rdsosreport.txt" to a USB stick or /b
01: oot                                                                         
01: after mounting them and attach it to a bug report.                          
01:                                                                             
01:                                                                             
00: dracut:/#