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-rw-r--r--arch/arm64/kernel/hibernate.c5
-rw-r--r--arch/arm64/kernel/mte.c9
-rw-r--r--arch/arm64/mm/copypage.c9
-rw-r--r--arch/arm64/mm/mteswap.c9
4 files changed, 32 insertions, 0 deletions
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 42003774d261..9c9f47e9f7f4 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -371,6 +371,11 @@ static void swsusp_mte_restore_tags(void)
unsigned long pfn = xa_state.xa_index;
struct page *page = pfn_to_online_page(pfn);
+ /*
+ * It is not required to invoke page_kasan_tag_reset(page)
+ * at this point since the tags stored in page->flags are
+ * already restored.
+ */
mte_restore_page_tags(page_address(page), tags);
mte_free_tag_storage(tags);
diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c
index 78f81c459cb1..3a6216b0002e 100644
--- a/arch/arm64/kernel/mte.c
+++ b/arch/arm64/kernel/mte.c
@@ -34,6 +34,15 @@ static void mte_sync_page_tags(struct page *page, pte_t *ptep, bool check_swap)
return;
}
+ page_kasan_tag_reset(page);
+ /*
+ * We need smp_wmb() in between setting the flags and clearing the
+ * tags because if another thread reads page->flags and builds a
+ * tagged address out of it, there is an actual dependency to the
+ * memory access, but on the current thread we do not guarantee that
+ * the new page->flags are visible before the tags were updated.
+ */
+ smp_wmb();
mte_clear_page_tags(page_address(page));
}
diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c
index 70a71f38b6a9..b5447e53cd73 100644
--- a/arch/arm64/mm/copypage.c
+++ b/arch/arm64/mm/copypage.c
@@ -23,6 +23,15 @@ void copy_highpage(struct page *to, struct page *from)
if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) {
set_bit(PG_mte_tagged, &to->flags);
+ page_kasan_tag_reset(to);
+ /*
+ * We need smp_wmb() in between setting the flags and clearing the
+ * tags because if another thread reads page->flags and builds a
+ * tagged address out of it, there is an actual dependency to the
+ * memory access, but on the current thread we do not guarantee that
+ * the new page->flags are visible before the tags were updated.
+ */
+ smp_wmb();
mte_copy_page_tags(kto, kfrom);
}
}
diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c
index c52c1847079c..7c4ef56265ee 100644
--- a/arch/arm64/mm/mteswap.c
+++ b/arch/arm64/mm/mteswap.c
@@ -53,6 +53,15 @@ bool mte_restore_tags(swp_entry_t entry, struct page *page)
if (!tags)
return false;
+ page_kasan_tag_reset(page);
+ /*
+ * We need smp_wmb() in between setting the flags and clearing the
+ * tags because if another thread reads page->flags and builds a
+ * tagged address out of it, there is an actual dependency to the
+ * memory access, but on the current thread we do not guarantee that
+ * the new page->flags are visible before the tags were updated.
+ */
+ smp_wmb();
mte_restore_page_tags(page_address(page), tags);
return true;