Re: unusual sector error in "qemu-img convert.."

[Lukas Straub]

On Sun, 24 Nov 2019 23:56:17 +1100
Russell Davie <address@hidden> wrote:

> Hi Qemu mailing list
>
> This is my first time here, I hope this is the right place for this!
>
> qemu-img is reporting a sector error that is preventing the compression of
> an Windows7 image by qemu-img.  This sector error cannot be found with
> either the "qemu-img check" or internal Windows 7 "chkdsk" commands. The
> host physical disk  (SSD or spinning HD) has no reported sector errors
> using gparted.
>
> Command is:
> qemu-img convert -c -f qcow2 Windows_7.qcow2 -O qcow2
> Windows_7-compressed.qcow2
>
> Error is:
> qemu-img: error while reading sector 57492736: Input/output error
>
> checking image with qemu-img shows no errors:
> # qemu-img check  Windows_7.qcow2
> No errors were found on the image.
> 916112/917504 = 99.85% allocated, 22.81% fragmented, 9.55% compressed
> clusters
> Image end offset: 56792645632
>
> This error occurs at the same sector with the versions of Qemu (with
> compile flags):
>  4.0.0-r50 (aio alsa bzip2 caps curl fdt filecaps gnutls gtk jpeg lzo
> ncurses nfs nls opengl pin-upstream-blobs png pulseaudio sasl sdl seccomp
> smartcard spice usb usbredir vhost-net virtfs vnc xattr xfs xkb)
>
>  4.1.0 (aio alsa bzip2 caps curl fdt filecaps gnutls gtk jpeg lzo ncurses
> nfs nls opengl oss pin-upstream-blobs png pulseaudio sasl sdl seccomp
> smartcard spice usb usbredir vhost-net virtfs vnc xattr xfs xkb)
>
> Host OS: Gentoo / Calculate Linux
> Host Kernel: 4.19.77-calculate #1 SMP PREEMPT x86_64
> Host CPU: i7-3740QM Intel
>
> thanks in advance with help on this!
>
> Russell

Hi,
Did you check in our kernel log that it really is not a HDD failure?
"qemu-img check" does only check the metadata AFAIK. Does "cat Windows_7.qcow2 
> /dev/null"
work without error?

Regards,
Lukas Straub