diff options
Diffstat (limited to 'arch/arm64/kernel/mte.c')
| -rw-r--r-- | arch/arm64/kernel/mte.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index 56e79807006c..52a0638ed967 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -10,6 +10,8 @@ #include <linux/sched.h> #include <linux/sched/mm.h> #include <linux/string.h> +#include <linux/swap.h> +#include <linux/swapops.h> #include <linux/thread_info.h> #include <linux/uio.h> @@ -18,15 +20,30 @@ #include <asm/ptrace.h> #include <asm/sysreg.h> +static void mte_sync_page_tags(struct page *page, pte_t *ptep, bool check_swap) +{ + pte_t old_pte = READ_ONCE(*ptep); + + if (check_swap && is_swap_pte(old_pte)) { + swp_entry_t entry = pte_to_swp_entry(old_pte); + + if (!non_swap_entry(entry) && mte_restore_tags(entry, page)) + return; + } + + mte_clear_page_tags(page_address(page)); +} + void mte_sync_tags(pte_t *ptep, pte_t pte) { struct page *page = pte_page(pte); long i, nr_pages = compound_nr(page); + bool check_swap = nr_pages == 1; /* if PG_mte_tagged is set, tags have already been initialised */ for (i = 0; i < nr_pages; i++, page++) { if (!test_and_set_bit(PG_mte_tagged, &page->flags)) - mte_clear_page_tags(page_address(page)); + mte_sync_page_tags(page, ptep, check_swap); } } |