Re: [PATCH v2 2/2] arm64: mm: implement vmemmap_check_pmd for arm64

From: Zhenhua Huang
Date: Tue Dec 31 2024 - 02:19:05 EST




On 2024/12/31 14:59, Anshuman Khandual wrote:
A very small nit regarding the subject line. The callback
vmemmap_check_pmd() is already present on arm64 platform
which is rather incomplete. Something like this might be
better.

arm64/mm: Test for pmd_sect() in vmemmap_check_pmd()

On 12/30/24 13:18, Zhenhua Huang wrote:


On 2024/12/27 10:57, Anshuman Khandual wrote:
However it does not really check the entry to be a section mapping which it should.
Returning pmd_sect(READ_ONCE(*pmdp)) is the right thing, which should have been the
case from the beginning when vmemmap_check_pmd() was added. I guess because arm64's
original vmemmap_populate() checked only for vmemmap_verify() as well. So probably
this does not need a "Fixes: " tag.

Hi Anshuman,

I agree, will remove "Fixes: " tag in next patchset

Could you please send a V3 of this patch separately instead
and not part of this series as they are not really related.

Sure, Thanks Anshuman. Will gather information and update after coming back from Holiday!


But after implementing the following changes

1) Use READ_ONCE() as indicated earlier
2) Drop the "Fixes: " tag
3) Update the commit message explaining why pmd_sect() is
required here and how the originally commit missed that
4) Update the subject line