diff options
Diffstat (limited to 'arch/arm64/mm/copypage.c')
| -rw-r--r-- | arch/arm64/mm/copypage.c | 38 |
1 files changed, 35 insertions, 3 deletions
diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c index a7bb20055ce0..cd5912ba617b 100644 --- a/arch/arm64/mm/copypage.c +++ b/arch/arm64/mm/copypage.c @@ -18,15 +18,47 @@ void copy_highpage(struct page *to, struct page *from) { void *kto = page_address(to); void *kfrom = page_address(from); + struct folio *src = page_folio(from); + struct folio *dst = page_folio(to); + unsigned int i, nr_pages; copy_page(kto, kfrom); if (kasan_hw_tags_enabled()) page_kasan_tag_reset(to); - if (system_supports_mte() && page_mte_tagged(from)) { - /* It's a new page, shouldn't have been tagged yet */ - WARN_ON_ONCE(!try_page_mte_tagging(to)); + if (!system_supports_mte()) + return; + + if (folio_test_hugetlb(src)) { + if (!folio_test_hugetlb_mte_tagged(src) || + from != folio_page(src, 0)) + return; + + folio_try_hugetlb_mte_tagging(dst); + + /* + * Populate tags for all subpages. + * + * Don't assume the first page is head page since + * huge page copy may start from any subpage. + */ + nr_pages = folio_nr_pages(src); + for (i = 0; i < nr_pages; i++) { + kfrom = page_address(folio_page(src, i)); + kto = page_address(folio_page(dst, i)); + mte_copy_page_tags(kto, kfrom); + } + folio_set_hugetlb_mte_tagged(dst); + } else if (page_mte_tagged(from)) { + /* + * Most of the time it's a new page that shouldn't have been + * tagged yet. However, folio migration can end up reusing the + * same page without untagging it. Ignore the warning if the + * page is already tagged. + */ + try_page_mte_tagging(to); + mte_copy_page_tags(kto, kfrom); set_page_mte_tagged(to); } |