diff options
Diffstat (limited to 'arch/arm64/mm/mmu.c')
| -rw-r--r-- | arch/arm64/mm/mmu.c | 55 |
1 files changed, 51 insertions, 4 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 19feb6fe05b2..db7c4e6ae57b 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -43,15 +43,27 @@ #define NO_CONT_MAPPINGS BIT(1) #define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */ -u64 idmap_t0sz = TCR_T0SZ(VA_BITS_MIN); -u64 idmap_ptrs_per_pgd = PTRS_PER_PGD; +int idmap_t0sz __ro_after_init; -u64 __section(".mmuoff.data.write") vabits_actual; +#if VA_BITS > 48 +u64 vabits_actual __ro_after_init = VA_BITS_MIN; EXPORT_SYMBOL(vabits_actual); +#endif + +u64 kimage_vaddr __ro_after_init = (u64)&_text; +EXPORT_SYMBOL(kimage_vaddr); u64 kimage_voffset __ro_after_init; EXPORT_SYMBOL(kimage_voffset); +u32 __boot_cpu_mode[] = { BOOT_CPU_MODE_EL2, BOOT_CPU_MODE_EL1 }; + +/* + * The booting CPU updates the failed status @__early_cpu_boot_status, + * with MMU turned off. + */ +long __section(".mmuoff.data.write") __early_cpu_boot_status; + /* * Empty_zero_page is a special page that is used for zero-initialized data * and COW. @@ -763,22 +775,57 @@ static void __init map_kernel(pgd_t *pgdp) kasan_copy_shadow(pgdp); } +static void __init create_idmap(void) +{ + u64 start = __pa_symbol(__idmap_text_start); + u64 size = __pa_symbol(__idmap_text_end) - start; + pgd_t *pgd = idmap_pg_dir; + u64 pgd_phys; + + /* check if we need an additional level of translation */ + if (VA_BITS < 48 && idmap_t0sz < (64 - VA_BITS_MIN)) { + pgd_phys = early_pgtable_alloc(PAGE_SHIFT); + set_pgd(&idmap_pg_dir[start >> VA_BITS], + __pgd(pgd_phys | P4D_TYPE_TABLE)); + pgd = __va(pgd_phys); + } + __create_pgd_mapping(pgd, start, start, size, PAGE_KERNEL_ROX, + early_pgtable_alloc, 0); + + if (IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) { + extern u32 __idmap_kpti_flag; + u64 pa = __pa_symbol(&__idmap_kpti_flag); + + /* + * The KPTI G-to-nG conversion code needs a read-write mapping + * of its synchronization flag in the ID map. + */ + __create_pgd_mapping(pgd, pa, pa, sizeof(u32), PAGE_KERNEL, + early_pgtable_alloc, 0); + } +} + void __init paging_init(void) { pgd_t *pgdp = pgd_set_fixmap(__pa_symbol(swapper_pg_dir)); + extern pgd_t init_idmap_pg_dir[]; + + idmap_t0sz = 63UL - __fls(__pa_symbol(_end) | GENMASK(VA_BITS_MIN - 1, 0)); map_kernel(pgdp); map_mem(pgdp); pgd_clear_fixmap(); - cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); + cpu_replace_ttbr1(lm_alias(swapper_pg_dir), init_idmap_pg_dir); init_mm.pgd = swapper_pg_dir; memblock_phys_free(__pa_symbol(init_pg_dir), __pa_symbol(init_pg_end) - __pa_symbol(init_pg_dir)); memblock_allow_resize(); + + create_idmap(); } /* |