Comment 36 for bug 1840122

I am occasionally seeing this again with the Impish live-server (subiquity) daily ISO images. I saw this happening only on ppc64el and on arm64, and only on preseeded installs (via answers.yaml).

This doesn't prevent the installation from succeeding: what fails is just the post-install reboot. Hard-rebooting the system results in the installed system booting correctly.

This is not easy to reproduce, I went with something on these lines:

for i in {1..100}; do
    echo "Round $i"
    virt-install --os-variant ubuntu18.04 --name paride-impish-preseed --memory 2048 --disk image.qcow2 --disk answers.img --cdrom impish-live-server-ppc64el.iso --noautoconsole --wait -1 || break;
    sleep 5;
    virsh destroy paride-impish-preseed || break;
    virsh undefine paride-impish-preseed || break;
done

When the problem happens virt-install will never exit as the installer system gets caught in the "SQUASHFS error: Failed to read block" error loop. I'm attaching the answers.yaml baked in answers.img (see LP: #1946398 on how to create the answers image file).

Note: that answers.yaml preseeds the installation of a snap. I have the impression that it increases the probability of hitting the failure.

=== kernel log excerpt on failure ===

[ 78.374287] EXT4-fs (vda2): mounted filesystem with ordered data mode. Opts: (null). Quota mode: none.
[ 79.296032] overlayfs: "xino" feature enabled using 32 upper inode bits.
[ 134.464075] overlayfs: "xino" feature enabled using 2 upper inode bits.
[ 355.493023] SGI XFS with ACLs, security attributes, realtime, quota, no debug enabled
[ 355.513889] JFS: nTxBlock = 459, nTxLock = 3673
[ 355.536975] ntfs: driver 2.1.32 [Flags: R/O MODULE].
[ 355.564466] QNX4 filesystem 0.2.3 registered.
[ 355.648190] Btrfs loaded, crc32c=crc32c-vpmsum, zoned=yes
[ 372.037306] VFS: busy inodes on changed media sr0
[ 372.039566] sr 0:0:0:2: [sr0] tag#19 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.039572] sr 0:0:0:2: [sr0] tag#19 Sense Key : Not Ready [current]
[ 372.039575] sr 0:0:0:2: [sr0] tag#19 Add. Sense: Medium not present
[ 372.039578] sr 0:0:0:2: [sr0] tag#19 CDB: Read(10) 28 00 00 00 a6 35 00 00 20 00
[ 372.039580] blk_update_request: I/O error, dev sr0, sector 170196 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
[ 372.039633] sr 0:0:0:2: [sr0] tag#20 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.039636] sr 0:0:0:2: [sr0] tag#20 Sense Key : Not Ready [current]
[ 372.039638] sr 0:0:0:2: [sr0] tag#20 Add. Sense: Medium not present
[ 372.039641] sr 0:0:0:2: [sr0] tag#20 CDB: Read(10) 28 00 00 00 a6 35 00 00 20 00
[ 372.039642] blk_update_request: I/O error, dev sr0, sector 170196 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
[ 372.039651] blk_update_request: I/O error, dev loop0, sector 36870 op 0x0:(READ) flags 0x800 phys_seg 1 prio class 0
[ 372.051333] SQUASHFS error: Failed to read block 0x1200dd0: -5
[ 372.051337] SQUASHFS error: Unable to read data cache entry [1200dd0]
[ 372.051339] SQUASHFS error: Unable to read page, block 1200dd0, size 8380
[ 372.051461] sr 0:0:0:2: [sr0] tag#21 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.051465] sr 0:0:0:2: [sr0] tag#21 Sense Key : Not Ready [current]
[ 372.051468] sr 0:0:0:2: [sr0] tag#21 Add. Sense: Medium not present
[ 372.051471] sr 0:0:0:2: [sr0] tag#21 CDB: Read(10) 28 00 00 00 a6 35 00 00 20 00
[ 372.051473] blk_update_request: I/O error, dev sr0, sector 170196 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
[ 372.051482] blk_update_request: I/O error, dev loop0, sector 36870 op 0x0:(READ) flags 0x800 phys_seg 1 prio class 0
[ 372.051489] SQUASHFS error: Failed to read block 0x1200dd0: -5
[ 372.051545] sr 0:0:0:2: [sr0] tag#22 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.051548] sr 0:0:0:2: [sr0] tag#22 Sense Key : Not Ready [current]
[ 372.051550] sr 0:0:0:2: [sr0] tag#22 Add. Sense: Medium not present
[ 372.051553] sr 0:0:0:2: [sr0] tag#22 CDB: Read(10) 28 00 00 00 a6 35 00 00 20 00
[ 372.051554] blk_update_request: I/O error, dev sr0, sector 170196 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
[ 372.051562] blk_update_request: I/O error, dev loop0, sector 36870 op 0x0:(READ) flags 0x800 phys_seg 1 prio class 0
[ 372.051568] SQUASHFS error: Failed to read block 0x1200dd0: -5
[ 372.052908] sr 0:0:0:2: [sr0] tag#23 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.052912] sr 0:0:0:2: [sr0] tag#23 Sense Key : Not Ready [current]
[ 372.052915] sr 0:0:0:2: [sr0] tag#23 Add. Sense: Medium not present
[ 372.052917] sr 0:0:0:2: [sr0] tag#23 CDB: Read(10) 28 00 00 01 56 55 00 00 20 00
[ 372.052919] blk_update_request: I/O error, dev sr0, sector 350548 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
[ 372.052964] sr 0:0:0:2: [sr0] tag#24 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.052967] sr 0:0:0:2: [sr0] tag#24 Sense Key : Not Ready [current]
[ 372.052970] sr 0:0:0:2: [sr0] tag#24 Add. Sense: Medium not present
[ 372.052972] sr 0:0:0:2: [sr0] tag#24 CDB: Read(10) 28 00 00 01 56 55 00 00 20 00
[ 372.052974] blk_update_request: I/O error, dev sr0, sector 350548 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
[ 372.052981] blk_update_request: I/O error, dev loop0, sector 217262 op 0x0:(READ) flags 0x800 phys_seg 1 prio class 0
[ 372.052988] SQUASHFS error: Failed to read block 0x6a15d64: -5
[ 372.052989] SQUASHFS error: Unable to read data cache entry [6a15d64]
[ 372.052991] SQUASHFS error: Unable to read page, block 6a15d64, size 81b0
[ 372.053043] sr 0:0:0:2: [sr0] tag#25 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.053046] sr 0:0:0:2: [sr0] tag#25 Sense Key : Not Ready [current]
[ 372.053048] sr 0:0:0:2: [sr0] tag#25 Add. Sense: Medium not present
[ 372.053051] sr 0:0:0:2: [sr0] tag#25 CDB: Read(10) 28 00 00 01 56 55 00 00 20 00
[ 372.053061] SQUASHFS error: Failed to read block 0x6a15d64: -5
[ 372.053112] sr 0:0:0:2: [sr0] tag#26 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.053115] sr 0:0:0:2: [sr0] tag#26 Sense Key : Not Ready [current]
[ 372.053117] sr 0:0:0:2: [sr0] tag#26 Add. Sense: Medium not present
[ 372.053119] sr 0:0:0:2: [sr0] tag#26 CDB: Read(10) 28 00 00 01 56 55 00 00 20 00
[ 372.053128] SQUASHFS error: Failed to read block 0x6a15d64: -5
[ 372.054012] sr 0:0:0:2: [sr0] tag#27 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.054016] sr 0:0:0:2: [sr0] tag#27 Sense Key : Not Ready [current]
[ 372.054018] sr 0:0:0:2: [sr0] tag#27 Add. Sense: Medium not present
[ 372.054021] sr 0:0:0:2: [sr0] tag#27 CDB: Read(10) 28 00 00 01 56 55 00 00 20 00
[ 372.054067] sr 0:0:0:2: [sr0] tag#28 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE cmd_age=0s
[ 372.054069] sr 0:0:0:2: [sr0] tag#28 Sense Key : Not Ready [current]
[ 372.054072] sr 0:0:0:2: [sr0] tag#28 Add. Sense: Medium not present
[ 372.054074] sr 0:0:0:2: [sr0] tag#28 CDB: Read(10) 28 00 00 01 56 55 00 00 20 00
[ 372.054084] SQUASHFS error: Failed to read block 0x6a0f0c8: -5
[ 372.054086] SQUASHFS error: Unable to read data cache entry [6a0f0c8]
[ 372.054087] SQUASHFS error: Unable to read page, block 6a0f0c8, size 69a4
[ 372.054188] SQUASHFS error: Failed to read block 0x6a0f0c8: -5
[ 372.054286] SQUASHFS error: Failed to read block 0x6a0f0c8: -5
[ 372.063004] SQUASHFS error: Failed to read block 0x6c9d578: -5
[ 372.063007] SQUASHFS error: Unable to read data cache entry [6c9d578]
[ 372.063008] SQUASHFS error: Unable to read page, block 6c9d578, size 7f2c
[ 372.063070] SQUASHFS error: Failed to read block 0x6c9d578: -5
[ 372.063128] SQUASHFS error: Failed to read block 0x6c9d578: -5
[ 372.129910] SQUASHFS error: Failed to read block 0x440bbc8: -5
[ 372.130062] SQUASHFS error: Failed to read block 0x440bbc8: -5
[ 372.130200] SQUASHFS error: Failed to read block 0x440bbc8: -5