diff options
Diffstat (limited to 'tests/qemu-iotests/060')
| -rwxr-xr-x | tests/qemu-iotests/060 | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/tests/qemu-iotests/060 b/tests/qemu-iotests/060 index af8ed9f39a..f0116aab1d 100755 --- a/tests/qemu-iotests/060 +++ b/tests/qemu-iotests/060 @@ -138,6 +138,32 @@ $QEMU_IMG snapshot -a foo "$TEST_IMG" _check_test_img $QEMU_IO -c "$OPEN_RO" -c "read -P 1 0 512" | _filter_qemu_io +echo +echo "=== Testing overlap while COW is in flight ===" +echo +# compat=0.10 is required in order to make the following discard actually +# unallocate the sector rather than make it a zero sector - we want COW, after +# all. +IMGOPTS='compat=0.10' _make_test_img 1G +# Write two clusters, the second one enforces creation of an L2 table after +# the first data cluster. +$QEMU_IO -c 'write 0k 64k' -c 'write 512M 64k' "$TEST_IMG" | _filter_qemu_io +# Discard the first cluster. This cluster will soon enough be reallocated and +# used for COW. +$QEMU_IO -c 'discard 0k 64k' "$TEST_IMG" | _filter_qemu_io +# Now, corrupt the image by marking the second L2 table cluster as free. +poke_file "$TEST_IMG" '131084' "\x00\x00" # 0x2000c +# Start a write operation requiring COW on the image stopping it right before +# doing the read; then, trigger the corruption prevention by writing anything to +# any unallocated cluster, leading to an attempt to overwrite the second L2 +# table. Finally, resume the COW write and see it fail (but not crash). +echo "open -o file.driver=blkdebug $TEST_IMG +break cow_read 0 +aio_write 0k 1k +wait_break 0 +write 64k 64k +resume 0" | $QEMU_IO | _filter_qemu_io + # success, all done echo "*** done" rm -f $seq.full |