On Thu, Sep 26, 2024 at 3:58 PM Baokun Li <libaokun1@xxxxxxxxxx> wrote: > > On 2024/9/26 19:32, Aleksandr Mikhalitsyn wrote: > >>> Question to you and Jan. Do you guys think that it makes sense to try > >>> to create a minimal reproducer for this problem without Incus/LXD involved? > >>> (only e2fsprogs, lvm tools, etc) > >>> > >>> I guess this test can be put in the xfstests test suite, right? > >>> > >>> Kind regards, > >>> Alex > >> I think it makes sense, and it's good to have more use cases to look > >> around some corners. If you have an idea, let it go. > > Minimal reproducer: > > > > mkdir -p /tmp/ext4_crash/mnt > > EXT4_CRASH_IMG="/tmp/ext4_crash/disk.img" > > rm -f $EXT4_CRASH_IMG > > truncate $EXT4_CRASH_IMG --size 25MiB > > EXT4_CRASH_DEV=$(losetup --find --nooverlap --direct-io=on --show > > $EXT4_CRASH_IMG) > > mkfs.ext4 -E nodiscard,lazy_itable_init=0,lazy_journal_init=0 $EXT4_CRASH_DEV > > mount $EXT4_CRASH_DEV /tmp/ext4_crash/mnt > > truncate $EXT4_CRASH_IMG --size 3GiB > > losetup -c $EXT4_CRASH_DEV > > resize2fs $EXT4_CRASH_DEV > > > Hi Alex, > > This replicator didn't replicate the issue in my VM, so I took a deeper > look. The reproduction of the problem requires the following: That's weird. Have just tried once again and it reproduces the issue: root@ubuntu:/home/ubuntu# mkdir -p /tmp/ext4_crash/mnt EXT4_CRASH_IMG="/tmp/ext4_crash/disk.img" rm -f $EXT4_CRASH_IMG truncate $EXT4_CRASH_IMG --size 25MiB EXT4_CRASH_DEV=$(losetup --find --nooverlap --direct-io=on --show $EXT4_CRASH_IMG) mkfs.ext4 -E nodiscard,lazy_itable_init=0,lazy_journal_init=0 $EXT4_CRASH_DEV mount $EXT4_CRASH_DEV /tmp/ext4_crash/mnt truncate $EXT4_CRASH_IMG --size 3GiB losetup -c $EXT4_CRASH_DEV resize2fs $EXT4_CRASH_DEV mke2fs 1.47.0 (5-Feb-2023) Creating filesystem with 6400 4k blocks and 6400 inodes Allocating group tables: done Writing inode tables: done Creating journal (1024 blocks): done Writing superblocks and filesystem accounting information: done resize2fs 1.47.0 (5-Feb-2023) Filesystem at /dev/loop4 is mounted on /tmp/ext4_crash/mnt; on-line resizing required old_desc_blocks = 1, new_desc_blocks = 1 Segmentation fault My kernel's commit hash is 684a64bf32b6e488004e0ad7f0d7e922798f65b6 Maybe it somehow depends on the resize2fs version? Kind regards, Alex > > o_group = flexbg_size * 2 * n; > o_size = (o_group + 1) * group_size; > n_group: [o_group + flexbg_size, o_group + flexbg_size * 2) > > Take n=1,flexbg_size=16 as an example: > last:47 > |----------------|----------------|o---------------|--------------n-| > old:32 >>> new:62 > > Thus the replicator can be simplified as: > > img=test.img > truncate -s 600M $img > mkfs.ext4 -F $img -b 1024 -G 16 264M > dev=`losetup -f --show $img` > mkdir -p /tmp/test > mount $dev /tmp/test > resize2fs $dev 504M > > > -- > Cheers, > Baokun >
