Re: [PATCH 01/18] mm: add a kunmap_local_dirty helper

[Herbert Xu]

On Thu, Jun 17, 2021 at 08:01:57PM -0700, Ira Weiny wrote:
>
> > +		flush_kernel_dcache_page(__page);		\
> 
> Is this required on 32bit systems?  Why is kunmap_flush_on_unmap() not
> sufficient on 64bit systems?  The normal kunmap_local() path does that.
> 
> I'm sorry but I did not see a conclusion to my query on V1. Herbert implied the
> he just copied from the crypto code.[1]  I'm concerned that this _dirty() call
> is just going to confuse the users of kmap even more.  So why can't we get to
> the bottom of why flush_kernel_dcache_page() needs so much logic around it
> before complicating the general kernel users.
> 
> I would like to see it go away if possible.

This thread may be related:

https://lwn.net/Articles/240249/

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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