diff options
Diffstat (limited to 'arch/s390/kernel/alternative.c')
-rw-r--r-- | arch/s390/kernel/alternative.c | 75 |
1 files changed, 24 insertions, 51 deletions
diff --git a/arch/s390/kernel/alternative.c b/arch/s390/kernel/alternative.c index 1ac5f707dd70..8d5d0de35de0 100644 --- a/arch/s390/kernel/alternative.c +++ b/arch/s390/kernel/alternative.c @@ -1,68 +1,41 @@ // SPDX-License-Identifier: GPL-2.0 -#include <linux/module.h> -#include <linux/cpu.h> -#include <linux/smp.h> -#include <asm/text-patching.h> + +#include <linux/uaccess.h> +#include <asm/nospec-branch.h> +#include <asm/abs_lowcore.h> #include <asm/alternative.h> #include <asm/facility.h> -#include <asm/nospec-branch.h> - -static int __initdata_or_module alt_instr_disabled; - -static int __init disable_alternative_instructions(char *str) -{ - alt_instr_disabled = 1; - return 0; -} - -early_param("noaltinstr", disable_alternative_instructions); -static void __init_or_module __apply_alternatives(struct alt_instr *start, - struct alt_instr *end) +void __apply_alternatives(struct alt_instr *start, struct alt_instr *end, unsigned int ctx) { - struct alt_instr *a; u8 *instr, *replacement; + struct alt_instr *a; + bool replace; /* * The scan order should be from start to end. A later scanned * alternative code can overwrite previously scanned alternative code. */ for (a = start; a < end; a++) { + if (!(a->ctx & ctx)) + continue; + switch (a->type) { + case ALT_TYPE_FACILITY: + replace = test_facility(a->data); + break; + case ALT_TYPE_SPEC: + replace = nobp_enabled(); + break; + case ALT_TYPE_LOWCORE: + replace = have_relocated_lowcore(); + break; + default: + replace = false; + } + if (!replace) + continue; instr = (u8 *)&a->instr_offset + a->instr_offset; replacement = (u8 *)&a->repl_offset + a->repl_offset; - - if (!__test_facility(a->facility, alt_stfle_fac_list)) - continue; s390_kernel_write(instr, replacement, a->instrlen); } } - -void __init_or_module apply_alternatives(struct alt_instr *start, - struct alt_instr *end) -{ - if (!alt_instr_disabled) - __apply_alternatives(start, end); -} - -extern struct alt_instr __alt_instructions[], __alt_instructions_end[]; -void __init apply_alternative_instructions(void) -{ - apply_alternatives(__alt_instructions, __alt_instructions_end); -} - -static void do_sync_core(void *info) -{ - sync_core(); -} - -void text_poke_sync(void) -{ - on_each_cpu(do_sync_core, NULL, 1); -} - -void text_poke_sync_lock(void) -{ - cpus_read_lock(); - text_poke_sync(); - cpus_read_unlock(); -} |