diff options
| author |   David Hildenbrand <david@redhat.com> | 2024-12-03 11:20:50 +0100 |
|---|---|---|
| committer |   Andrew Morton <akpm@linux-foundation.org> | 2025-01-13 22:40:44 -0800 |
| commit | dd467f92db404ca2e061889ad1b6dd6221390222 (patch) | |
| tree | 930abe7f42e2973e7f172497af7de974027124c9 | |
| parent | mm/vma: move __vm_munmap() to mm/vma.c (diff) | |
| download | wireguard-linux-dd467f92db404ca2e061889ad1b6dd6221390222.tar.xz wireguard-linux-dd467f92db404ca2e061889ad1b6dd6221390222.zip | |
mm/memory_hotplug: move debug_pagealloc_map_pages() into online_pages_range()
In the near future, we want to have a single way to handover PageOffline
pages to the buddy, whereby they could have:
(a) Never been exposed to the buddy before: kept PageOffline when onlining
the memory block.
(b) Been allocated from the buddy, for example using
alloc_contig_range() to then be set PageOffline,
Let's start by making generic_online_page()->__free_pages_core() less
special compared to ordinary page freeing (e.g., free_contig_range()),
and perform the debug_pagealloc_map_pages() call unconditionally, even
when the online callback might decide to keep the pages offline.
All pages are already initialized with PageOffline, so nobody touches them
either way.
Link: https://lkml.kernel.org/r/20241203102050.223318-1-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/memory_hotplug.c | 10 | ||||
| -rw-r--r-- | mm/page_alloc.c | 6 |
2 files changed, 9 insertions, 7 deletions
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c43b4e7fb298..20af14e695c7 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -650,6 +650,7 @@ static void online_pages_range(unsigned long start_pfn, unsigned long nr_pages) * this and the first chunk to online will be pageblock_nr_pages. */ for (pfn = start_pfn; pfn < end_pfn;) { + struct page *page = pfn_to_page(pfn); int order; /* @@ -664,7 +665,14 @@ static void online_pages_range(unsigned long start_pfn, unsigned long nr_pages) else order = MAX_PAGE_ORDER; - (*online_page_callback)(pfn_to_page(pfn), order); + /* + * Exposing the page to the buddy by freeing can cause + * issues with debug_pagealloc enabled: some archs don't + * like double-unmappings. So treat them like any pages that + * were allocated from the buddy. + */ + debug_pagealloc_map_pages(page, 1 << order); + (*online_page_callback)(page, order); pfn += (1UL << order); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a887ba2cc91d..75de3711784e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1295,12 +1295,6 @@ void __meminit __free_pages_core(struct page *page, unsigned int order, set_page_count(p, 0); } - /* - * Freeing the page with debug_pagealloc enabled will try to - * unmap it; some archs don't like double-unmappings, so - * map it first. - */ - debug_pagealloc_map_pages(page, nr_pages); adjust_managed_page_count(page, nr_pages); } else { for (loop = 0; loop < nr_pages; loop++, p++) { |