From ba5b0333a847ac026725122e085b2fea9e1674bc Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Feb 2024 13:29:09 +0100 Subject: arm64: mm: omit redundant remap of kernel image Now that the early kernel mapping is created with all the right attributes and segment boundaries, there is no longer a need to recreate it and switch to it. This also means we no longer have to copy the kasan shadow or some parts of the fixmap from one set of page tables to the other. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20240214122845.2033971-68-ardb+git@google.com Signed-off-by: Catalin Marinas --- arch/arm64/mm/fixmap.c | 34 ---------------------------------- 1 file changed, 34 deletions(-) (limited to 'arch/arm64/mm/fixmap.c') diff --git a/arch/arm64/mm/fixmap.c b/arch/arm64/mm/fixmap.c index 6fc17b2e1714..9404f282f829 100644 --- a/arch/arm64/mm/fixmap.c +++ b/arch/arm64/mm/fixmap.c @@ -170,37 +170,3 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot) return dt_virt; } - -/* - * Copy the fixmap region into a new pgdir. - */ -void __init fixmap_copy(pgd_t *pgdir) -{ - if (!READ_ONCE(pgd_val(*pgd_offset_pgd(pgdir, FIXADDR_TOT_START)))) { - /* - * The fixmap falls in a separate pgd to the kernel, and doesn't - * live in the carveout for the swapper_pg_dir. We can simply - * re-use the existing dir for the fixmap. - */ - set_pgd(pgd_offset_pgd(pgdir, FIXADDR_TOT_START), - READ_ONCE(*pgd_offset_k(FIXADDR_TOT_START))); - } else if (CONFIG_PGTABLE_LEVELS > 3) { - pgd_t *bm_pgdp; - p4d_t *bm_p4dp; - pud_t *bm_pudp; - /* - * The fixmap shares its top level pgd entry with the kernel - * mapping. This can really only occur when we are running - * with 16k/4 levels, so we can simply reuse the pud level - * entry instead. - */ - BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES)); - bm_pgdp = pgd_offset_pgd(pgdir, FIXADDR_TOT_START); - bm_p4dp = p4d_offset(bm_pgdp, FIXADDR_TOT_START); - bm_pudp = pud_set_fixmap_offset(bm_p4dp, FIXADDR_TOT_START); - pud_populate(&init_mm, bm_pudp, lm_alias(bm_pmd)); - pud_clear_fixmap(); - } else { - BUG(); - } -} -- cgit v1.2.3