From fe94793e555f650fab656649521fc38aaab4874e Mon Sep 17 00:00:00 2001 From: Yunlei He Date: Fri, 22 Jul 2016 19:08:31 +0800 Subject: [PATCH] f2fs: get victim segment again after new cp Previous selected segment may become free after write_checkpoint, if we do garbage collect on this segment, and then new_curseg happen to reuse it, it may cause f2fs_bug_on as below. panic+0x154/0x29c do_garbage_collect+0x15c/0xaf4 f2fs_gc+0x2dc/0x444 f2fs_balance_fs.part.22+0xcc/0x14c f2fs_balance_fs+0x28/0x34 f2fs_map_blocks+0x5ec/0x790 f2fs_preallocate_blocks+0xe0/0x100 f2fs_file_write_iter+0x64/0x11c new_sync_write+0xac/0x11c vfs_write+0x144/0x1e4 SyS_write+0x60/0xc0 Here, maybe we check sit and ssa type during reset_curseg. So, we check segment is stale or not, and select a new victim to avoid this. Signed-off-by: Yunlei He Signed-off-by: Jaegeuk Kim --- fs/f2fs/gc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index de6c41c32c62..06cfb94cc3db 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -908,10 +908,13 @@ gc_more: * enough free sections, we should flush dent/node blocks and do * garbage collections. */ - if (__get_victim(sbi, &segno, gc_type) || prefree_segments(sbi)) + if (__get_victim(sbi, &segno, gc_type) || + prefree_segments(sbi)) { write_checkpoint(sbi, &cpc); - else if (has_not_enough_free_secs(sbi, 0)) + segno = NULL_SEGNO; + } else if (has_not_enough_free_secs(sbi, 0)) { write_checkpoint(sbi, &cpc); + } } if (segno == NULL_SEGNO && !__get_victim(sbi, &segno, gc_type)) -- 2.34.1