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Date:   Tue, 16 Jul 2019 15:00:47 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Nadav Amit <namit@vmware.com>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>, Borislav Petkov <bp@suse.de>,
        Toshi Kani <toshi.kani@hpe.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH 0/3] resource: find_next_iomem_res() improvements
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On Tue, 18 Jun 2019 21:56:43 +0000 Nadav Amit <namit@vmware.com> wrote:

> > ...and is constant for the life of the device and all subsequent mappings.
> > 
> >> Perhaps you want to cache the cachability-mode in vma->vm_page_prot (which I
> >> see being done in quite a few cases), but I don’t know the code well enough
> >> to be certain that every vma should have a single protection and that it
> >> should not change afterwards.
> > 
> > No, I'm thinking this would naturally fit as a property hanging off a
> > 'struct dax_device', and then create a version of vmf_insert_mixed()
> > and vmf_insert_pfn_pmd() that bypass track_pfn_insert() to insert that
> > saved value.
> 
> Thanks for the detailed explanation. I’ll give it a try (the moment I find
> some free time). I still think that patch 2/3 is beneficial, but based on
> your feedback, patch 3/3 should be dropped.

It has been a while.  What should we do with

resource-fix-locking-in-find_next_iomem_res.patch
resource-avoid-unnecessary-lookups-in-find_next_iomem_res.patch

?