Re: [PATCH v4 0/7] mtrr, mm, x86: Enhance MTRR checks for huge I/O mapping

Toshi Kani
2015-04-27T14:50:25Z

On Fri, 2015-04-03 at 09:22 -0600, Toshi Kani wrote:
> On Fri, 2015-04-03 at 08:33 +0200, Ingo Molnar wrote:
> > * Andrew Morton <akpm@linux-foundation.org> wrote:
> >
> > > On Tue, 24 Mar 2015 16:08:34 -0600 Toshi Kani <toshi.kani@hp.com> wrote:
> > >
> > > > This patchset enhances MTRR checks for the kernel huge I/O mapping,
> > > > which was enabled by the patchset below:
> > > > https://lkml.org/lkml/2015/3/3/589
> > > >
> > > > The following functional changes are made in patch 7/7.
> > > > - Allow pud_set_huge() and pmd_set_huge() to create a huge page
> > > > mapping to a range covered by a single MTRR entry of any memory
> > > > type.
> > > > - Log a pr_warn() message when a specified PMD map range spans more
> > > > than a single MTRR entry. Drivers should make a mapping request
> > > > aligned to a single MTRR entry when the range is covered by MTRRs.
> > > >
> > >
> > > OK, I grabbed these after barely looking at them, to get them a bit of
> > > runtime testing.
> > >
> > > I'll await guidance from the x86 maintainers regarding next steps?
> >
> > Could you please send the current version of them over to us if your
> > testing didn't find any problems?
> >
> > I'd like to take a final look and have them cook in the x86 tree as
> > well for a while and want to preserve your testing effort.
>
> This patchset is on top of the following patches in the -mm tree.
> (Patches apply from the bottom to the top.)

Ingo,

The following patches (2 got squashed to 1) went to 4.1-rc1, but this
patch-set is still sitting in the -mm tree. I confirmed that the
patch-set applies cleanly to 4.1-rc1. Please take a final look and let
me know if you have any comment.

Thanks,
-Toshi

> 2. Build error fixes and cleanups
> http://ozlabs.org/~akpm/mmotm/broken-out/x86-mm-support-huge-kva-mappings-on-x86-fix.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/mm-change-vunmap-to-tear-down-huge-kva-mappings-fix.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/mm-change-ioremap-to-set-up-huge-i-o-mappings-fix.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/lib-add-huge-i-o-map-capability-interfaces-fix.patch
>
> 1. Kernel huge I/O mapping support
> http://ozlabs.org/~akpm/mmotm/broken-out/x86-mm-support-huge-kva-mappings-on-x86.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/x86-mm-support-huge-i-o-mapping-capability-i-f.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/mm-change-vunmap-to-tear-down-huge-kva-mappings.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/mm-change-ioremap-to-set-up-huge-i-o-mappings.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/lib-add-huge-i-o-map-capability-interfaces.patch
> http://ozlabs.org/~akpm/mmotm/broken-out/mm-change-__get_vm_area_node-to-use-fls_long.patch
>
> Thanks,
> -Toshi
>