diff options
Diffstat (limited to 'arch/arm64/mm/mmu.c')
| -rw-r--r-- | arch/arm64/mm/mmu.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 267d2b79d52d..fe68a48c64cb 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -525,6 +525,29 @@ static int __init parse_rodata(char *arg) } early_param("rodata", parse_rodata); +#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 +static int __init map_entry_trampoline(void) +{ + extern char __entry_tramp_text_start[]; + + pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; + phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start); + + /* The trampoline is always mapped and can therefore be global */ + pgprot_val(prot) &= ~PTE_NG; + + /* Map only the text into the trampoline page table */ + memset(tramp_pg_dir, 0, PGD_SIZE); + __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE, + prot, pgd_pgtable_alloc, 0); + + /* ...as well as the kernel page table */ + __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot); + return 0; +} +core_initcall(map_entry_trampoline); +#endif + /* * Create fine-grained mappings for the kernel. */ |