Re: [PATCH v3 1/3] mm: replace memmap_context by meminit_context

From: David Hildenbrand
Date: Wed Sep 16 2020 - 03:52:46 EST


On 16.09.20 09:47, Laurent Dufour wrote:
> Le 16/09/2020 à 09:40, Greg Kroah-Hartman a écrit :
>> On Wed, Sep 16, 2020 at 09:29:22AM +0200, Laurent Dufour wrote:
>>> Le 16/09/2020 à 08:33, Greg Kroah-Hartman a écrit :
>>>> On Tue, Sep 15, 2020 at 03:26:24PM +0200, Laurent Dufour wrote:
>>>>> The memmap_context enum is used to detect whether a memory operation is due
>>>>> to a hot-add operation or happening at boot time.
>>>>>
>>>>> Make it general to the hotplug operation and rename it as meminit_context.
>>>>>
>>>>> There is no functional change introduced by this patch
>>>>>
>>>>> Suggested-by: David Hildenbrand <david@xxxxxxxxxx>
>>>>> Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxx>
>>>>> ---
>>>>> arch/ia64/mm/init.c | 6 +++---
>>>>> include/linux/mm.h | 2 +-
>>>>> include/linux/mmzone.h | 11 ++++++++---
>>>>> mm/memory_hotplug.c | 2 +-
>>>>> mm/page_alloc.c | 10 +++++-----
>>>>> 5 files changed, 18 insertions(+), 13 deletions(-)
>>>>
>>>> <formletter>
>>>>
>>>> This is not the correct way to submit patches for inclusion in the
>>>> stable kernel tree. Please read:
>>>> https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
>>>> for how to do this properly.
>>>>
>>>> </formletter>
>>>
>>> Hi Greg,
>>>
>>> I'm sorry, I read that document few days ago before sending the series and
>>> again this morning, but I can't figure out what I missed (following option
>>> 1).
>>>
>>> Should the "Cc: stable@xxxxxxxxxxxxxxx" tag be on each patch of the series
>>> even if the whole series has been sent to stable ?
>>
>> That should be on any patch you expect to show up in a stable kernel
>> release.
>>
>>> Should the whole series sent again (v4) instead of sending a fix as a reply to ?
>>
>> It's up to the maintainer what they want, but as it is, this patch is
>> not going to end up in stable kernel release (which it looks like is the
>> right thing to do...)
>
> Thanks a lot Greg.
>
> I'll send that single patch again with the Cc: stable tag.

I think Andrew can add that when sending upstream.

While a single patch to fix + backport would be nicer, I don't see an
easy (!ugly) way to achieve the same without this cleanup.

1. We could rework patch #2 to pass a simple boolean flag, and a
follow-on patch to pass the context. Not sure if that's any better.

2. We could rework patch #2 to pass memmap_context first, and modify
patch #1 to also rename this instance.

Maybe 2. might be reasonable (not sure if worth the trouble). @Greg any
preference?

>
> I don't think the patch 3 need to be backported, it doesn't fix any issue and
> with the patch 1 and 2 applied, the BUG_ON should no more be triggered easily.

Agreed.


--
Thanks,

David / dhildenb