Re: [PATCH v3 2/2] mm: Introduce kernelcore=mirror option

From: Kamezawa Hiroyuki
Date: Wed Dec 16 2015 - 21:54:01 EST


On 2015/12/17 11:47, Xishi Qiu wrote:
> On 2015/12/17 9:38, Izumi, Taku wrote:
>
>> Dear Xishi,
>>
>> Sorry for late.
>>
>>> -----Original Message-----
>>> From: Xishi Qiu [mailto:qiuxishi@xxxxxxxxxx]
>>> Sent: Friday, December 11, 2015 6:44 PM
>>> To: Izumi, Taku/泉 拓
>>> Cc: Luck, Tony; linux-kernel@xxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx; Kamezawa, Hiroyuki/亀澤 寛
>>> 之; mel@xxxxxxxxx; Hansen, Dave; matt@xxxxxxxxxxxxxxxxxxx
>>> Subject: Re: [PATCH v3 2/2] mm: Introduce kernelcore=mirror option
>>>
>>> On 2015/12/11 13:53, Izumi, Taku wrote:
>>>
>>>> Dear Xishi,
>>>>
>>>>> Hi Taku,
>>>>>
>>>>> Whether it is possible that we rewrite the fallback function in buddy system
>>>>> when zone_movable and mirrored_kernelcore are both enabled?
>>>>
>>>> What does "when zone_movable and mirrored_kernelcore are both enabled?" mean ?
>>>>
>>>> My patchset just provides a new way to create ZONE_MOVABLE.
>>>>
>>>
>>> Hi Taku,
>>>
>
> Hi Taku,
>
> We can NOT specify kernelcore= "nn[KMG]" and "mirror" at the same time.
> So when we use "mirror", in fact, the movable zone is a new zone. I think it is
> more appropriate with this name "mirrored zone", and also we can rewrite the
> fallback function in buddy system in this case.

kernelcore ="mirrored zone" ?

BTW, let me confirm.

ZONE_NORMAL = mirrored
ZONE_MOVABLE = not mirrored.

so, the new zone is "not-mirrored" zone.

Now, fallback function is

movable -> normal -> DMA.

As Tony requested, we may need a knob to stop a fallback in "movable->normal", later.

Thanks,
-Kame






--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/