Ok I found something:
[ 489.178839] blk_update_request: I/O error, dev vda, sector 194494297
[ 489.179101] blk_update_request: I/O error, dev vda, sector 194494297
[ 489.179595] blk_update_request: I/O error, dev vda, sector 133236593
[ 489.179638] blk_update_request: I/O error, dev vda, sector 133236593
[ 489.181588] blk_update_request: I/O error, dev vda, sector 133237465
[ 489.181697] blk_update_request: I/O error, dev vda, sector 133237465
[ 489.181862] blk_update_request: I/O error, dev vda, sector 97740209
[ 489.181935] blk_update_request: I/O error, dev vda, sector 97740209
[ 627.701815] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702038] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702101] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702136] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702147] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702166] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702185] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702203] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702213] blk_update_request: I/O error, dev vda, sector 148651065
[ 627.702223] blk_update_request: I/O error, dev vda, sector 148651065
[ 638.878711] blk_update_request: 236 callbacks suppressed
[ 638.878716] blk_update_request: I/O error, dev vda, sector 124166937
[ 638.878774] blk_update_request: I/O error, dev vda, sector 124166937
[ 638.878830] blk_update_request: I/O error, dev vda, sector 124166937
[ 649.190009] blk_update_request: I/O error, dev vda, sector 59924889
[ 649.190190] blk_update_request: I/O error, dev vda, sector 59924889
[ 649.190302] blk_update_request: I/O error, dev vda, sector 59924889
Is this a hardware problem? The image is stored in a lvm volume on a mdadm raid.