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Date:   Fri, 9 Jun 2023 10:50:11 +0800
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Subject: Re: [PATCH v2 3/3] fs: Use delayed shrinker unregistration
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To:     Andrew Morton <akpm@linux-foundation.org>,
        Dave Chinner <david@fromorbit.com>
Cc:     Theodore Ts'o <tytso@mit.edu>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Kirill Tkhai <tkhai@ya.ru>, vbabka@suse.cz,
        viro@zeniv.linux.org.uk, brauner@kernel.org, djwong@kernel.org,
        hughd@google.com, paulmck@kernel.org, muchun.song@linux.dev,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org,
        Qi Zheng <zhengqi.arch@bytedance.com>
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From:   Qi Zheng <qi.zheng@linux.dev>
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On 2023/6/9 08:27, Andrew Morton wrote:
> On Fri, 9 Jun 2023 09:17:54 +1000 Dave Chinner <david@fromorbit.com> wrote:
> 
>>> Given that we're at -rc5 now, and the file system folks didn't get
>>> consulted until fairly late in the progress, and the fact that this
>>> may cause use-after-free problems that could lead to security issues,
>>> perhaps we shoould consider reverting the SRCU changeover now, and try
>>> again for the next merge window?
>>
>> Yes, please, because I think we can fix this in a much better way
>> and make things a whole lot simpler at the same time.
> 
> Qi Zheng, if agreeable could you please prepare and send reverts of
> 475733dda5a ("mm: vmscan: add shrinker_srcu_generation") and of
> f95bdb700bc6bb74 ("mm: vmscan: make global slab shrink lockless")?

OK. After reading the proposal suggested by Dave, I think it is more
feasible. I will revert the previous changes ASAP, and then try to
implement Dave's proposal.

Thanks,
Qi

> 
> Thanks.