Re: [PATCH 07/13] s390: make setup_zero_pages() use memblock

From: Heiko Carstens
Date: Fri Mar 07 2025 - 10:29:39 EST


On Thu, Mar 06, 2025 at 08:51:17PM +0200, Mike Rapoport wrote:
> From: "Mike Rapoport (Microsoft)" <rppt@xxxxxxxxxx>
>
> Allocating the zero pages from memblock is simpler because the memory is
> already reserved.
>
> This will also help with pulling out memblock_free_all() to the generic
> code and reducing code duplication in arch::mem_init().
>
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
> ---
> arch/s390/mm/init.c | 14 +++-----------
> 1 file changed, 3 insertions(+), 11 deletions(-)

Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx>

> - empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
> + empty_zero_page = (unsigned long)memblock_alloc(PAGE_SIZE << order, order);
> if (!empty_zero_page)
> panic("Out of memory in setup_zero_pages");

This could have been converted to memblock_alloc_or_panic(), but I
guess this can also be done at a later point in time.