On Sat, May 30, 2020 at 11:48:09AM +0800, Zheng Bin wrote:
> When a filesystem is mounting on a loop device and on a loop ioctl
s/mounting/mounted/ ?
> LOOP_SET_STATUS64, because of kill_bdev, buffer_head mappings are getting
> destroyed.
> kill_bdev
> truncate_inode_pages
> truncate_inode_pages_range
> do_invalidatepage
> block_invalidatepage
> discard_buffer -->clear BH_Mapped flag
>
> sb_bread
> __bread_gfp
> bh = __getblk_gfp
> -->discard_buffer clear BH_Mapped flag
> __bread_slow
> submit_bh
> submit_bh_wbc
> BUG_ON(!buffer_mapped(bh)) --> hit this BUG_ON
>
> Fixes: 5db470e229e2 ("loop: drop caches if offset or block_size are changed")
> Signed-off-by: Zheng Bin <zhengbin13@xxxxxxxxxx>
Otherwise this looks reasonable:
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Can you also add a patch to now mark kill_bdev static in block_dev.c,
as this removed the last external users?
