[v2] powerpc/mm: Ensure "special" zones are empty

Michael Ellerman mpe at ellerman.id.au
Tue Jun 21 10:40:53 AEST 2016


On Wed, 2016-11-05 at 09:22:18 UTC, Oliver O'Halloran wrote:
> The mm zone mechanism was traditionally used by arch specific code to
> partition memory into allocation zones. However there are several zones
> that are managed by the mm subsystem rather than the architecture. Most
> architectures set the max PFN of these special zones to zero, however on
> powerpc we set them to ~0ul. This, in conjunction with a bug in
> free_area_init_nodes() results in all of system memory being placed in
> ZONE_DEVICE when enabled. Device memory cannot be used for regular kernel
> memory allocations so this will cause a kernel panic at boot. Given the
> planned addition of more mm managed zones (ZONE_CMA) we should aim to be
> consistent with every other architecture and set the max PFN for these
> zones to zero.
> 
> Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
> Reviewed-by: Balbir Singh <bsingharora at gmail.com>
> Cc: linux-mm at kvack.org

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/3079abe555511031e2ba5d1e21

cheers


More information about the Linuxppc-dev mailing list