I had a VM running over night with:
[1] Running while :; do
smartctl -a /dev/sda > /dev/null;
done &
[2]- Running while :; do
ls --color=auto -lR / > /dev/null 2> /dev/null;
done &
[3]+ Running while :; do
sleep $(( $RANDOM % 100 )); sync; echo 3 > /proc/sys/vm/drop_caches;
done &
and I haven't seen the issue. :(
FWIW, I'm using the ahci qemu driver:
-drive file=disk-image.raw,if=none,id=drive0,format=raw \
-device ahci,id=bus0 \
-device ide-drive,bus=bus0.0,drive=drive0
Does this match your qemu instance?