4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jaegeuk Kim <[email protected]> commit 164a63fa6b384e30ceb96ed80bc7dc3379bc0960 upstream. This reverts commit 66110abc4c931f879d70e83e1281f891699364bf. If we clear the cold data flag out of the writeback flow, we can miscount -1 by end_io, which incurs a deadlock caused by all I/Os being blocked during heavy GC. Balancing F2FS Async: - IO (CP: 1, Data: -1, Flush: ( 0 0 1), Discard: ( ... GC thread: IRQ - move_data_page() - set_page_dirty() - clear_cold_data() - f2fs_write_end_io() - type = WB_DATA_TYPE(page); here, we get wrong type - dec_page_count(sbi, type); - f2fs_wait_on_page_writeback() Cc: <[email protected]> Reported-and-Tested-by: Park Ju Hyung <[email protected]> Reviewed-by: Chao Yu <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/f2fs/data.c | 4 ---- 1 file changed, 4 deletions(-) --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2190,10 +2190,6 @@ static int f2fs_set_data_page_dirty(stru if (!PageUptodate(page)) SetPageUptodate(page); - /* don't remain PG_checked flag which was set during GC */ - if (is_cold_data(page)) - clear_cold_data(page); - if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) { if (!IS_ATOMIC_WRITTEN_PAGE(page)) { register_inmem_page(inode, page);
