RE:(2) [PATCH v1] f2fs: fix uninitialized skipped_gc_rwsem

From: Yonggil Song
Date: Wed Feb 15 2023 - 21:02:26 EST


On 2023/2/15 10:48, Yonggil Song wrote:
>> When f2fs skipped a gc round during victim migration, there was a bug which
>> would skip all upcoming gc rounds unconditionally because skipped_gc_rwsem
>> was not initialized. It fixes the bug by correctly initializing the
>> skipped_gc_rwsem inside the gc loop.
>
>It makes sense to me.
>
>>
>> Fixes: d147ea4adb96 ("f2fs: introduce f2fs_gc_control to consolidate f2fs_gc parameters")
>
>How does this commits introduce the bug?

Oh, sorry I've got wrong hash.
I'll send right hash on PATCH v2.

Thanks for your comment.

>
>Thanks,
>
>> Signed-off-by: Yonggil Song <yonggil.song@xxxxxxxxxxx>
>>
>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>> index b22f49a6f128..81d326abaac1 100644
>> --- a/fs/f2fs/gc.c
>> +++ b/fs/f2fs/gc.c
>> @@ -1786,8 +1786,8 @@ int f2fs_gc(struct f2fs_sb_info *sbi, struct f2fs_gc_control *gc_control)
>> prefree_segments(sbi));
>>
>> cpc.reason = __get_cp_reason(sbi);
>> - sbi->skipped_gc_rwsem = 0;
>> gc_more:
>> + sbi->skipped_gc_rwsem = 0;
>> if (unlikely(!(sbi->sb->s_flags & SB_ACTIVE))) {
>> ret = -EINVAL;
>> goto stop;