The patch titled
Subject: mm/page_alloc.c: avoid allocating highmem pages via alloc_pages_exact[_nid]
has been added to the -mm tree. Its filename is
mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact.patch
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------------------------------------------------------
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm/page_alloc.c: avoid allocating highmem pages via alloc_pages_exact[_nid]
Don't use with __GFP_HIGHMEM because page_address() cannot represent
highmem pages without kmap(). Newly allocated pages would leak as
page_address() will return NULL for highmem pages here. But It works now
because the callers do not specify __GFP_HIGHMEM now.
Link: https://lkml.kernel.org/r/20210902121242.41607-6-linmiaohe@xxxxxxxxxx
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/mm/page_alloc.c~mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact
+++ a/mm/page_alloc.c
@@ -5604,8 +5604,8 @@ void *alloc_pages_exact(size_t size, gfp
unsigned int order = get_order(size);
unsigned long addr;
- if (WARN_ON_ONCE(gfp_mask & __GFP_COMP))
- gfp_mask &= ~__GFP_COMP;
+ if (WARN_ON_ONCE(gfp_mask & (__GFP_COMP | __GFP_HIGHMEM)))
+ gfp_mask &= ~(__GFP_COMP | __GFP_HIGHMEM);
addr = __get_free_pages(gfp_mask, order);
return make_alloc_exact(addr, order, size);
@@ -5629,8 +5629,8 @@ void * __meminit alloc_pages_exact_nid(i
unsigned int order = get_order(size);
struct page *p;
- if (WARN_ON_ONCE(gfp_mask & __GFP_COMP))
- gfp_mask &= ~__GFP_COMP;
+ if (WARN_ON_ONCE(gfp_mask & (__GFP_COMP | __GFP_HIGHMEM)))
+ gfp_mask &= ~(__GFP_COMP | __GFP_HIGHMEM);
p = alloc_pages_node(nid, gfp_mask, order);
if (!p)
_
Patches currently in -mm which might be from linmiaohe@xxxxxxxxxx are
mm-page_allocc-remove-meaningless-vm_bug_on-in-pindex_to_order.patch
mm-page_allocc-simplify-the-code-by-using-macro-k.patch
mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch
mm-page_allocc-use-helper-function-zone_spans_pfn.patch
mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact.patch
mm-page_isolation-fix-potential-missing-call-to-unset_migratetype_isolate.patch
mm-page_isolation-guard-against-possible-putback-unisolated-page.patch
mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch
mm-zsmallocc-close-race-window-between-zs_pool_dec_isolated-and-zs_unregister_migration.patch
mm-zsmallocc-combine-two-atomic-ops-in-zs_pool_dec_isolated.patch
