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From:   "Luck, Tony" <tony.luck@intel.com>
To:     Aili Yao <yaoaili@kingsoft.com>
CC:     =?iso-2022-jp?B?SE9SSUdVQ0hJIE5BT1lBKBskQktZOH0hIUQ+TGkbKEIp?= 
        <naoya.horiguchi@nec.com>, Oscar Salvador <osalvador@suse.de>,
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        "yangfeng1@kingsoft.com" <yangfeng1@kingsoft.com>,
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Subject: RE: [PATCH v3] mm,hwpoison: return -EHWPOISON when page already
 poisoned
Thread-Topic: [PATCH v3] mm,hwpoison: return -EHWPOISON when page already
 poisoned
Thread-Index: AQHXJiCcYSfsREicYE+l/w+vDcmt1aqfzHoAgAEYvwCAAHK6QA==
Date:   Fri, 2 Apr 2021 15:11:20 +0000
Message-ID: <a10c7838216e4a10b4fd5ebb0f1108a1@intel.com>
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>> Combined with my "mutex" patch (to get rid of races where 2nd process returns
>> early, but first process is still looking for mappings to unmap and tasks
>> to signal) this patch moves forward a bit. But I think it needs an
>> additional change here in kill_me_maybe() to just "return" if there is a
>> EHWPOISON return from memory_failure()
>> 
> Got this, Thanks for your reply!
> I will dig into this!

One problem with this approach is when the first task to find poison
fails to complete actions. Then the poison pages are not unmapped,
and just returning from kill_me_maybe() gets into a loop :-(

-Tony