Thanks for the report, sorry for the late reply: This has been fixed in commit 84c26520d3c1c9ff4a10455748139463278816d5 (included in the 2.7.0 release).
** Changed in: qemu Status: New => Fix Released -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1592590 Title: Prevent qemu-img resize from causing "Active L1 table too large" Status in QEMU: Fix Released Bug description: This commit prevents qemu from overallocating if qcow2 image is too big (whatever that means): https://lists.gnu.org/archive/html/qemu- devel/2014-07/msg01481.html However, `qemu-img resize` isn't protected by the same code and allows to go beyond that. root@nwkr-laptop ~virtkick/hdd # qemu-img resize 33_test_609dffde-eb51-4b75-918d-b814f1bcb526.qcow2 +100000T Image resized. Which then causes "Active L1 table too large" error that cannot be reversed. root@nwkr-laptop ~virtkick/hdd # qemu-img info 33_test_609dffde-eb51-4b75-918d-b814f1bcb526.qcow2 qemu-img: Could not open '33_test_609dffde-eb51-4b75-918d-b814f1bcb526.qcow2': Active L1 table too large root@nwkr-laptop ~virtkick/hdd # qemu-img resize 33_test_609dffde-eb51-4b75-918d-b814f1bcb526.qcow2 -100000T qemu-img: Could not open '33_test_609dffde-eb51-4b75-918d-b814f1bcb526.qcow2': Active L1 table too large I originally faces this bug when I passed wrong parameters to qemu-img in a programatic way which caused an image to go corrupt. It's good to protect user's images from being resized too much. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1592590/+subscriptions