Commit 25837227 authored by Mike Rapoport's avatar Mike Rapoport Committed by Zheng Zengkai
Browse files

mm: introduce memmap_alloc() to unify memory map allocation 

mainline inclusion
from mainline-v5.15-rc1
commit c803b3c8
category: bugfix
bugzilla: 186414, https://gitee.com/openeuler/kernel/issues/I5K7IY
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c803b3c8b3b70f306ee6300bf8acdd70ffd1441a

--------------------------------

There are several places that allocate memory for the memory map:
alloc_node_mem_map() for FLATMEM, sparse_buffer_init() and
__populate_section_memmap() for SPARSEMEM.

The memory allocated in the FLATMEM case is zeroed and it is never
poisoned, regardless of CONFIG_PAGE_POISON setting.

The memory allocated in the SPARSEMEM cases is not zeroed and it is
implicitly poisoned inside memblock if CONFIG_PAGE_POISON is set.

Introduce memmap_alloc() wrapper for memblock allocators that will be used
for both FLATMEM and SPARSEMEM cases and will makei memory map zeroing and
poisoning consistent for different memory models.

Link: https://lkml.kernel.org/r/20210714123739.16493-4-rppt@kernel.org


Signed-off-by: default avatarMike Rapoport <rppt@linux.ibm.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Conflicts:
	mm/page_alloc.c
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 2b35f08e

mm/internal.h

+4 −0
Original line number Diff line number Diff line
@@ -208,6 +208,10 @@ extern void zone_pcp_reset(struct zone *zone); 
extern void zone_pcp_disable(struct zone *zone);

extern void zone_pcp_enable(struct zone *zone);



extern void *memmap_alloc(phys_addr_t size, phys_addr_t align,

			  phys_addr_t min_addr,

			  int nid, bool exact_nid);



#if defined CONFIG_COMPACTION || defined CONFIG_CMA



/*

mm/page_alloc.c

+22 −2
Original line number Diff line number Diff line
@@ -6564,6 +6564,26 @@ void __meminit __weak arch_memmap_init(unsigned long size, int nid, 
{

}



void __init *memmap_alloc(phys_addr_t size, phys_addr_t align,

			  phys_addr_t min_addr, int nid, bool exact_nid)

{

	void *ptr;



	if (exact_nid)

		ptr = memblock_alloc_exact_nid_raw(size, align, min_addr,

						   MEMBLOCK_ALLOC_ACCESSIBLE,

						   nid);

	else

		ptr = memblock_alloc_try_nid_raw(size, align, min_addr,

						 MEMBLOCK_ALLOC_ACCESSIBLE,

						 nid);



	if (ptr && size > 0)

		page_init_poison(ptr, size);



	return ptr;

}



static int zone_batchsize(struct zone *zone)

{

#ifdef CONFIG_MMU
@@ -7297,8 +7317,8 @@ static void __ref alloc_node_mem_map(struct pglist_data *pgdat) 
		end = pgdat_end_pfn(pgdat);

		end = ALIGN(end, MAX_ORDER_NR_PAGES);

		size =  (end - start) * sizeof(struct page);

		map = memblock_alloc_node(size, SMP_CACHE_BYTES,

					  pgdat->node_id);

		map = memmap_alloc(size, SMP_CACHE_BYTES, MEMBLOCK_LOW_LIMIT,

				   pgdat->node_id, false);

		if (!map)

			panic("Failed to allocate %ld bytes for node %d memory map\n",

			      size, pgdat->node_id);

mm/sparse.c

+2 −4
Original line number Diff line number Diff line
@@ -453,8 +453,7 @@ struct page __init *__populate_section_memmap(unsigned long pfn, 
	if (map)

		return map;



	map = memblock_alloc_try_nid_raw(size, size, addr,

					  MEMBLOCK_ALLOC_ACCESSIBLE, nid);

	map = memmap_alloc(size, size, addr, nid, false);

	if (!map)

		panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d from=%pa\n",

		      __func__, size, PAGE_SIZE, nid, &addr);
@@ -481,8 +480,7 @@ static void __init sparse_buffer_init(unsigned long size, int nid) 
	 * and we want it to be properly aligned to the section size - this is

	 * especially the case for VMEMMAP which maps memmap to PMDs

	 */

	sparsemap_buf = memblock_alloc_exact_nid_raw(size, section_map_size(),

					addr, MEMBLOCK_ALLOC_ACCESSIBLE, nid);

	sparsemap_buf = memmap_alloc(size, section_map_size(), addr, nid, true);

	sparsemap_buf_end = sparsemap_buf + size;

}