loop device: print_req_error - blk_update_request I/O error

[EgervÃry Gergely]

Hi,

I'm mounting an ext4 filesystem residing on an AHCI SATA disk via loop:
  losetup -o 64424509440 --sizelimit 34359738368 /dev/loop0 /dev/sda
  mount -t ext4 /dev/loop0 /mnt

Works perfectly on <= 4.4.155 (latest version on 4.4.x longterm branch)

On 4.9.126 (longterm branch) I get these errors:
  blk_update_request: I/O error, /dev/loop0, sector 23778144
  blk_update_request: I/O error, /dev/loop0, sector 23789056
  blk_update_request: I/O error, /dev/loop0, sector 23791038
  ...

On 4.14.69 (longterm branch):
  print_req_error: I/O error, /dev/loop0, sector 22685550
  print_req_error: I/O error, /dev/loop0, sector 22696582
  print_req_error: I/O error, /dev/loop0, sector 22675034
  ...

and even on the latest stable 4.18.7:
  print_req_error: I/O error, /dev/loop0, sector 21044836
  print_req_error: I/O error, /dev/loop0, sector 22058444
  print_req_error: I/O error, /dev/loop0, sector 22858336
  ...

That's 100% reproducible on all my computers. They are amd64 desktop PCs
running unpatched vanilla kernels from kernel.org.

Any ideas?

I can provide more details if requested (.config, dmesg, etc.)
Thanks in advance.
--
Gergely EGERVARY