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Message-ID: <e1a6007d-24f2-5153-5382-f66391cbd0cb@bytedance.com>
Date:   Mon, 26 Sep 2022 16:41:19 +0800
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Subject: Re: [PATCH] mm: fix misuse of update_mmu_cache() in
 do_anonymous_page()
To:     David Hildenbrand <david@redhat.com>,
        Muchun Song <muchun.song@linux.dev>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Linux MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org,
        chris@zankel.net, jcmvbkbc@gmail.com, maobibo@loongson.cn
References: <20220924053239.91661-1-zhengqi.arch@bytedance.com>
 <3A09E40A-E2C5-4C6F-8550-DD0E17B7DAB9@linux.dev>
 <48590f80-fc58-bf67-5acf-082880a607b2@redhat.com>
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From:   Qi Zheng <zhengqi.arch@bytedance.com>
In-Reply-To: <48590f80-fc58-bf67-5acf-082880a607b2@redhat.com>
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On 2022/9/26 16:32, David Hildenbrand wrote:
> On 25.09.22 03:43, Muchun Song wrote:
>>
>>
>>> On Sep 24, 2022, at 13:32, Qi Zheng <zhengqi.arch@bytedance.com> wrote:
>>>
>>> As message in commit 7df676974359 ("mm/memory.c: Update local TLB
>>> if PTE entry exists") said, we should update local TLB only on the
>>> second thread. So fix the misuse of update_mmu_cache() by using
>>> update_mmu_tlb() in the do_anonymous_page().
>>>
>>> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
>>
>> The change looks good to me. However, I am not sure what is the 
>> user-visible
>> effect to xtensa users. So Cc xtensa’s maintainer and the author of 
>> 7df676974359
>> to double check this.
> 
> And if there is one, do we have a fixes tag?

IIUC, there's only a performance difference here, so maybe there's no
need to add the fixes tag?

> 

-- 
Thanks,
Qi