From: yohan.joung Date: Thu, 3 Apr 2025 23:21:06 +0000 (+0900) Subject: f2fs: prevent the current section from being selected as a victim during GC X-Git-Tag: v6.16-rc1~115^2~186 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d26fecb03e1f1069480d41fa2a6cea87ebbb89b8;p=thirdparty%2Fkernel%2Flinux.git f2fs: prevent the current section from being selected as a victim during GC 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 Signed-off-by: Chao Yu Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- 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); }