There is an issue reported in github, where an fs get corrupted
extent tree initialy, then I recommended --init-extent-tree.
Although --init-extent-tree indeed fixed the original problem, it caused
new problems, quite a lot of EXTENT_ITEMs now get bad generation number,
which failed to mount with v5.4.
The problem turns out to be a bug in backref repair code, which doesn't
initialize extent_record::generation, causing garbage in EXTENT_ITEMs.
This patch will:
- Fix the problem
Patch 1
- Enhance EXTENT_ITEM generation repair
Patch 2
- Make `btrfs check` able to detect such bad generation
Patch 3~4
- Add new test case for above ability
Patch 5
Qu Wenruo (5):
btrfs-progs: check: Initialize extent_record::generation member
btrfs-progs: check: Populate extent generation correctly for data
extents
btrfs-progs: check/lowmem: Detect invalid EXTENT_ITEM and EXTENT_DATA
generation
btrfs-progs: check/original: Detect invalid extent generation
btrfs-progs: fsck-tests: Make sure btrfs check can detect bad extent
item generation
check/main.c | 36 ++++++++++++++----
check/mode-lowmem.c | 19 +++++++++
.../bad_extent_item_gen.img.xz | Bin 0 -> 1916 bytes
.../test.sh | 19 +++++++++
4 files changed, 67 insertions(+), 7 deletions(-)
create mode 100644 tests/fsck-tests/044-invalid-extent-item-generation/bad_extent_item_gen.img.xz
create mode 100755 tests/fsck-tests/044-invalid-extent-item-generation/test.sh
--
2.24.1
