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Message-ID: <ad258412-2f8f-8e15-fbd0-c0933aeb1a6d@suse.cz>
Date:   Tue, 19 Jul 2022 16:21:32 +0200
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Subject: Re: [PATCH 1/3] mm/slub: fix the race between validate_slab and
 slab_free
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To:     Rongwei Wang <rongwei.wang@linux.alibaba.com>,
        akpm@linux-foundation.org, roman.gushchin@linux.dev,
        iamjoonsoo.kim@lge.com, rientjes@google.com, penberg@kernel.org,
        cl@linux.com
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>
References: <20220529081535.69275-1-rongwei.wang@linux.alibaba.com>
 <69462916-2d1c-dd50-2e64-b31c2b61690e@suse.cz>
 <5344e023-29f0-9285-a402-19e2a556dbb0@linux.alibaba.com>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <5344e023-29f0-9285-a402-19e2a556dbb0@linux.alibaba.com>
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On 7/19/22 16:15, Rongwei Wang wrote:
> 
...
>> +
>> +    slab_unlock(slab, &flags2);
>> +    spin_unlock_irqrestore(&n->list_lock, flags);
>> +    if (!ret)
>> +        slab_fix(s, "Object at 0x%p not freed", object);
>> +    if (slab_to_discard) {
>> +        stat(s, FREE_SLAB);
>> +        discard_slab(s, slab);
>> +    }
>> +
>> +    return ret;
>> +}
> I had test this patch, and it indeed deal with the bug that I described.

Thanks.

> Though I am also has prepared this part of code, your code is ok to me.

Aha, feel free to post your version, maybe it's simpler? We can compare.