ext4: initialize multi-block allocator before checking block descriptors
With EXT4FS_DEBUG ext4_count_free_clusters() will call
ext4_read_block_bitmap() without s_group_info initialized, so we need to
initialize multi-block allocator before.
And dependencies that must be solved, to allow this:
- multi-block allocator needs in group descriptors
- need to install s_op before initializing multi-block allocator,
because in ext4_mb_init_backend() new inode is created.
- initialize number of group desc blocks (s_gdb_count) otherwise
number of clusters returned by ext4_free_clusters_after_init() is not correct.
(see ext4_bg_num_gdb_nometa())
Here is the stack backtrace:
(gdb) bt
#0 ext4_get_group_info (group=0, sb=0xffff880079a10000) at ext4.h:2430
#1 ext4_validate_block_bitmap (sb=sb@entry=0xffff880079a10000,
desc=desc@entry=0xffff880056510000, block_group=block_group@entry=0,
bh=bh@entry=0xffff88007bf2b2d8) at balloc.c:358
#2 0xffffffff81232202 in ext4_wait_block_bitmap (sb=sb@entry=0xffff880079a10000,
block_group=block_group@entry=0,
bh=bh@entry=0xffff88007bf2b2d8) at balloc.c:476
#3 0xffffffff81232eaf in ext4_read_block_bitmap (sb=sb@entry=0xffff880079a10000,
block_group=block_group@entry=0) at balloc.c:489
#4 0xffffffff81232fc0 in ext4_count_free_clusters (sb=sb@entry=0xffff880079a10000) at balloc.c:665
#5 0xffffffff81259ffa in ext4_check_descriptors (first_not_zeroed=<synthetic pointer>,
sb=0xffff880079a10000) at super.c:2143
#6 ext4_fill_super (sb=sb@entry=0xffff880079a10000, data=<optimized out>,
data@entry=0x0 <irq_stack_union>, silent=silent@entry=0) at super.c:3851
...
Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
1 file changed