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Subject: [PATCH] =?UTF-8?q?mm:=20Give=20kmap=5Flock=20before=20call=20flus?= =?UTF-8?q?h=5Ftlb=5Fkernel=5Frang=EF=BC=8Cavoid=20kmap=5Fhigh=20deadlock?= =?UTF-8?q?=20V2.?=
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>> +++ b/mm/highmem.c
>> @@ -220,8 +220,11 @@ static void flush_all_zero_pkmaps(void)
>>  		set_page_address(page, NULL);
>>  		need_flush = 1;
>>  	}
>> -	if (need_flush)
>> +	if (need_flush) {
>> +		spin_unlock(&kmap_lock);

>should this be a raw spin_unlock(), or should it be unlock_kmap()?
>ie when ARCH_NEEDS_KMAP_HIGH_GET is set, do we also need to re-enable interrupts here?

Thanks! Using lock_map/unlock_kmap is better.
Patch V2 will be sent.
 
1.8.3.1