6.15-stable review patch. If anyone has any objections, please let me know.
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From: yohan.joung yohan.joung@sk.com
[ Upstream commit d26fecb03e1f1069480d41fa2a6cea87ebbb89b8 ]
When selecting a victim using next_victim_seg in a large section, the selected section might already have been cleared and designated as the new current section, making it actively in use. This behavior causes inconsistency between the SIT and SSA.
F2FS-fs (dm-54): Inconsistent segment (70961) type [0, 1] in SSA and SIT Call trace: dump_backtrace+0xe8/0x10c show_stack+0x18/0x28 dump_stack_lvl+0x50/0x6c dump_stack+0x18/0x28 f2fs_stop_checkpoint+0x1c/0x3c do_garbage_collect+0x41c/0x271c f2fs_gc+0x27c/0x828 gc_thread_func+0x290/0x88c kthread+0x11c/0x164 ret_from_fork+0x10/0x20
issue scenario segs_per_sec=2 - seg#0 and seg#1 are all dirty - all valid blocks are removed in seg#1 - gc select this sec and next_victim_seg=seg#0 - migrate seg#0, next_victim_seg=seg#1 - checkpoint -> sec(seg#0, seg#1) becomes free - allocator assigns sec(seg#0, seg#1) to curseg - gc tries to migrate seg#1
Fixes: e3080b0120a1 ("f2fs: support subsectional garbage collection") Signed-off-by: yohan.joung yohan.joung@sk.com Signed-off-by: Chao Yu chao@kernel.org Reviewed-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/segment.h | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 5fcb1f92d506f..503f6df690bf2 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -486,6 +486,11 @@ static inline void __set_test_and_free(struct f2fs_sb_info *sbi,
free_i->free_sections++;
+ if (GET_SEC_FROM_SEG(sbi, sbi->next_victim_seg[BG_GC]) == secno) + sbi->next_victim_seg[BG_GC] = NULL_SEGNO; + if (GET_SEC_FROM_SEG(sbi, sbi->next_victim_seg[FG_GC]) == secno) + sbi->next_victim_seg[FG_GC] = NULL_SEGNO; + unlock_out: spin_unlock(&free_i->segmap_lock); }