On Tue, 2020-12-08 at 12:04 +0100, Christoph Hellwig wrote: > can you send me details of your device mapper setup, e.g. which targets > are used, are they used on top of whole device or partitions. Do you > use partitions on top of the dm devices? Are any other stacking devices > involved? It is a standard RHEL8 installation using "autopart", so I don't think it uses any particular targets. It is just a plain LVM backed by ahci (sda2 and sdb1. Some other affected systems use smartpqi/NVM). The kernel has only dm-mirror enabled but I don't think it uses it anyway. # grep -i _DM_ .config | grep -v ^# CONFIG_BLK_DEV_DM_BUILTIN=y CONFIG_DM_MIRROR=m CONFIG_DM_UEVENT=y # lvdisplay --- Logical volume --- LV Path /dev/rhel_ibm-p9wr-10/home LV Name home VG Name rhel_ibm-p9wr-10 LV UUID ETS2PI-yedc-7AJ6-NUP2-uAYD-6api-bp9nqv LV Write Access read/write LV Status available # open 1 LV Size <3.57 TiB Current LE 934662 Segments 2 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 254:2 --- Logical volume --- LV Path /dev/rhel_ibm-p9wr-10/root LV Name root VG Name rhel_ibm-p9wr-10 LV UUID ozakb8-2DWE-YBI9-4nnc-gwk8-mMuf-s3EPsB LV Write Access read/write LV Status available # open 1 LV Size 70.00 GiB Current LE 17920 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 254:0 # pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name rhel_ibm-p9wr-10 PV Size <1.82 TiB / not usable 4.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 476675 Free PE 0 Allocated PE 476675 PV UUID 0Tv2Az-vx7S-HLPd-66Ff-tH6H-dte1-tjSZ7i --- Physical volume --- PV Name /dev/sdb1 VG Name rhel_ibm-p9wr-10 PV Size <1.82 TiB / not usable 4.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 476931 Free PE 0 Allocated PE 476931 PV UUID 4LfZJN-NxbJ-39OC-VBKP-jv5P-hciK-BOdiML # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 1 1.8T 0 disk ├─sda1 8:1 1 1G 0 part /boot └─sda2 8:2 1 1.8T 0 part ├─rhel_ibm--p9wr--10-root 254:0 0 70G 0 lvm / └─rhel_ibm--p9wr--10-home 254:2 0 3.6T 0 lvm /home sdb 8:16 1 1.8T 0 disk └─sdb1 8:17 1 1.8T 0 part └─rhel_ibm--p9wr--10-home 254:2 0 3.6T 0 lvm /home