4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yunlei He <heyunlei@xxxxxxxxxx> commit d4fdf8ba0e5808ba9ad6b44337783bd9935e0982 upstream. Mount fs with option noflush_merge, boot failed for illegal address fcc in function f2fs_issue_flush: if (!test_opt(sbi, FLUSH_MERGE)) { ret = submit_flush_wait(sbi); atomic_inc(&fcc->issued_flush); -> Here, fcc illegal return ret; } Signed-off-by: Yunlei He <heyunlei@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/f2fs/segment.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -493,6 +493,9 @@ int create_flush_cmd_control(struct f2fs init_waitqueue_head(&fcc->flush_wait_queue); init_llist_head(&fcc->issue_list); SM_I(sbi)->cmd_control_info = fcc; + if (!test_opt(sbi, FLUSH_MERGE)) + return err; + fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi, "f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev)); if (IS_ERR(fcc->f2fs_issue_flush)) { @@ -2539,7 +2542,7 @@ int build_segment_manager(struct f2fs_sb INIT_LIST_HEAD(&sm_info->sit_entry_set); - if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) { + if (!f2fs_readonly(sbi->sb)) { err = create_flush_cmd_control(sbi); if (err) return err;