[PATCH] ARM: mm: Fix the memblock allocation for LPAE machines

Russell King - ARM Linux
2014-02-05T23:48:15Z

On Wed, Feb 05, 2014 at 06:39:44PM -0500, Santosh Shilimkar wrote:
> Russell,
>
> On Saturday 01 February 2014 03:14 PM, Santosh Shilimkar wrote:
> > Commit ad6492b8 added much needed memblock_virt_alloc_low() and further
> > commit 07bacb3 {memblock, bootmem: restore goal for alloc_low} fixed the
> > issue with low memory limit thansk to Yinghai. But even after all these fixes,
> > there is still one case where the limit check done with ARCH_LOW_ADDRESS_LIMIT
> > for low memory fails. Russell pointed out the issue with 32 bit LPAE machines
> > in below thread.
> > https://lkml.org/lkml/2014/1/28/364
> >
> > Since on some LPAE machines where memory start address is beyond 4GB,
> > the low memory marker in memblock will be set to default
> > ARCH_LOW_ADDRESS_LIMIT which is wrong. We can fix this by letting
> > architectures set the ARCH_LOW_ADDRESS_LIMIT using another export
> > similar to memblock_set_current_limit() but am not sure whether
> > its worth the trouble. Tell me if you think otherwise.
> >
> > Rather am just trying to fix that one broken case using memblock_virt_alloc()
> > in setup code since the memblock.current_limit is updated appropriately
> > makes it work on all ARM 32 bit machines.
> >
> > Cc: Yinghai Lu <yinghai@kernel.org>
> > Cc: Russell King <linux@arm.linux.org.uk>
> > Cc: Strashko, Grygorii <grygorii.strashko@ti.com>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
> > ---
> Whats you say here ? We should get the fix for the
> issue. If you are ok, I can drop the patch in patch system.

Is this still an issue, or has Tejun fixed it by some other means? I've not
noticed anything being broken at the moment.

Can you confirm whether we still have an issue without this patch please?

Thanks.

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