From: Mike Rapoport rppt@linux.ibm.com
mainline inclusion from mainline-v5.15-rc1 commit c803b3c8b3b70f306ee6300bf8acdd70ffd1441a 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/?i...
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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: Mike Rapoport rppt@linux.ibm.com Cc: Michal Simek monstr@monstr.eu Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Conflicts: mm/page_alloc.c Signed-off-by: Liu Shixin liushixin2@huawei.com Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- mm/internal.h | 4 ++++ mm/page_alloc.c | 24 ++++++++++++++++++++++-- mm/sparse.c | 6 ++---- 3 files changed, 28 insertions(+), 6 deletions(-)
diff --git a/mm/internal.h b/mm/internal.h index 917b86b2870c..8ef8cdd929fa 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -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
/* diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d6085d48cb63..ff6fffec8770 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -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); diff --git a/mm/sparse.c b/mm/sparse.c index 5a48ea3e9968..d92a29000d66 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -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; }