From 8877e9e4290e004d0a39651f3b5839baaa481a93 Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Mon, 13 May 2019 22:39:36 +0800 Subject: [PATCH] mm: Enable Buddy allocation isolation for CDM nodes euler inclusion category: feature bugzilla: 11082 CVE: NA ------------------- This implements allocation isolation for CDM nodes in buddy allocator by discarding CDM memory zones all the time except in the cases where the gfp flag has got __GFP_THISNODE or the nodemask contains CDM nodes in cases where it is non NULL (explicit allocation request in the kernel or user process MPOL_BIND policy based requests). Signed-off-by: Anshuman Khandual Signed-off-by: zhong jiang Signed-off-by: Lijun Fang Reviewed-by: zhong jiang Signed-off-by: Yang Yingliang --- mm/page_alloc.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 5d11f5240837..cbfe0af6b303 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3284,6 +3284,21 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, struct page *page; unsigned long mark; + /* + * CDM nodes get skipped if the requested gfp flag + * does not have __GFP_THISNODE set or the nodemask + * does not have any CDM nodes in case the nodemask + * is non NULL (explicit allocation requests from + * kernel or user process MPOL_BIND policy which has + * CDM nodes). + */ + if (is_cdm_node(zone->zone_pgdat->node_id)) { + if (!(gfp_mask & __GFP_THISNODE)) { + if (!ac->nodemask) + continue; + } + } + if (cpusets_enabled() && (alloc_flags & ALLOC_CPUSET) && !__cpuset_zone_allowed(zone, gfp_mask)) -- GitLab