From fd6126484ceaa9d94db196931c10454090f3d677 Mon Sep 17 00:00:00 2001 From: Daeho Jeong Date: Wed, 27 May 2020 13:02:31 +0900 Subject: [PATCH] f2fs: protect new segment allocation in expand_inode_data Found a new segemnt allocation without f2fs_lock_op() in expand_inode_data(). So, when we do fallocate() for a pinned file and trigger checkpoint very frequently and simultaneously. F2FS gets stuck in the below code of do_checkpoint() forever. f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO); /* Wait for all dirty meta pages to be submitted for IO */ <= if fallocate() here, f2fs_wait_on_all_pages(sbi, F2FS_DIRTY_META); <= it'll wait forever. Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/file.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 67fd1c900eb4..dfa1ac2d751a 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1658,7 +1658,11 @@ next_alloc: down_write(&sbi->pin_sem); map.m_seg_type = CURSEG_COLD_DATA_PINNED; + + f2fs_lock_op(sbi); f2fs_allocate_new_segments(sbi, CURSEG_COLD_DATA); + f2fs_unlock_op(sbi); + err = f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_DIO); up_write(&sbi->pin_sem);