diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2025-03-10 10:28:55 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-03-16 17:40:26 -0700 |
| commit | 800f1059c99e2b39899bdc67a7593a7bea6375d8 (patch) | |
| tree | 3b96debff9db612f2a683bdb7918fddfcc14385c | |
| parent | b9c0e49abfca06f1a109acea834bcfc934f33f76 (diff) | |
mm/page_alloc: fix memory accept before watermarks gets initialized
Watermarks are initialized during the postcore initcall. Until then, all
watermarks are set to zero. This causes cond_accept_memory() to
incorrectly skip memory acceptance because a watermark of 0 is always met.
This can lead to a premature OOM on boot.
To ensure progress, accept one MAX_ORDER page if the watermark is zero.
Link: https://lkml.kernel.org/r/20250310082855.2587122-1-kirill.shutemov@linux.intel.com
Fixes: dcdfdd40fa82 ("mm: Add support for unaccepted memory")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Farrah Chen <farrah.chen@intel.com>
Reported-by: Farrah Chen <farrah.chen@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Cc: Ashish Kalra <ashish.kalra@amd.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
Cc: Thomas Lendacky <thomas.lendacky@amd.com>
Cc: <stable@vger.kernel.org> [6.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/page_alloc.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 94917c729120..542d25f77be8 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7004,7 +7004,7 @@ static inline bool has_unaccepted_memory(void) static bool cond_accept_memory(struct zone *zone, unsigned int order) { - long to_accept; + long to_accept, wmark; bool ret = false; if (!has_unaccepted_memory()) @@ -7013,8 +7013,18 @@ static bool cond_accept_memory(struct zone *zone, unsigned int order) if (list_empty(&zone->unaccepted_pages)) return false; + wmark = promo_wmark_pages(zone); + + /* + * Watermarks have not been initialized yet. + * + * Accepting one MAX_ORDER page to ensure progress. + */ + if (!wmark) + return try_to_accept_memory_one(zone); + /* How much to accept to get to promo watermark? */ - to_accept = promo_wmark_pages(zone) - + to_accept = wmark - (zone_page_state(zone, NR_FREE_PAGES) - __zone_watermark_unusable_free(zone, order, 0) - zone_page_state(zone, NR_UNACCEPTED)); |