On Wed, Nov 08, 2017 at 08:54:24AM +0800, Qu Wenruo wrote: > [BUG] > If we run btrfs with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y, it will > instantly cause kernel panic like: > > ------ > ... > assertion failed: 0, file: fs/btrfs/disk-io.c, line: 3853 > ... > Call Trace: > btrfs_mark_buffer_dirty+0x187/0x1f0 [btrfs] > setup_items_for_insert+0x385/0x650 [btrfs] > __btrfs_drop_extents+0x129a/0x1870 [btrfs] > ... > ----- > > [Cause] > Btrfs will call btrfs_check_leaf() in btrfs_mark_buffer_dirty() to check > if the leaf is valid with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y. > > However quite some btrfs_mark_buffer_dirty() callers(*) don't really > initialize its item data but only initialize its item pointers, leaving > item data uninitialized. > > This makes tree-checker catch uninitialized data as error, causing > such panic. > > *: These callers include but not limited to > setup_items_for_insert() > btrfs_split_item() > btrfs_expand_item() > > [Fix] > Add a new parameter @check_item_data to btrfs_check_leaf(). > With @check_item_data set to false, item data check will be skipped and > fallback to old btrfs_check_leaf() behavior. > > So we can still get early warning if we screw up item pointers, and > avoid false panic. > > Cc: Filipe Manana <fdman...@gmail.com> > Reported-by: Lakshmipathi.G <lakshmipath...@gmail.com> > Signed-off-by: Qu Wenruo <w...@suse.com>
Reviewed-by: David Sterba <dste...@suse.com> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
