diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index c0be0663425e..9ee6f879bce5 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -2561,24 +2561,26 @@ noinstr int smp_text_poke_int3_handler(struct pt_regs *regs) /** * smp_text_poke_batch_process() -- update instructions on live kernel on SMP - * @text_poke_array.vec: vector of instructions to patch - * @text_poke_array.nr_entries: number of entries in the vector * - * Modify multi-byte instruction by using int3 breakpoint on SMP. - * We completely avoid stop_machine() here, and achieve the - * synchronization using int3 breakpoint. + * Input state: + * text_poke_array.vec: vector of instructions to patch + * text_poke_array.nr_entries: number of entries in the vector + * + * Modify multi-byte instructions by using INT3 breakpoints on SMP. + * We completely avoid using stop_machine() here, and achieve the + * synchronization using INT3 breakpoints and SMP cross-calls. * * The way it is done: * - For each entry in the vector: - * - add a int3 trap to the address that will be patched - * - sync cores + * - add an INT3 trap to the address that will be patched + * - SMP sync all CPUs * - For each entry in the vector: * - update all but the first byte of the patched range - * - sync cores + * - SMP sync all CPUs * - For each entry in the vector: - * - replace the first byte (int3) by the first byte of + * - replace the first byte (INT3) by the first byte of the * replacing opcode - * - sync cores + * - SMP sync all CPUs */ static void smp_text_poke_batch_process(void) { @@ -2606,13 +2608,13 @@ static void smp_text_poke_batch_process(void) cond_resched(); /* - * Corresponding read barrier in int3 notifier for making sure the + * Corresponding read barrier in INT3 notifier for making sure the * text_poke_array.nr_entries and handler are correctly ordered wrt. patching. */ smp_wmb(); /* - * First step: add a int3 trap to the address that will be patched. + * First step: add a INT3 trap to the address that will be patched. */ for (i = 0; i < text_poke_array.nr_entries; i++) { text_poke_array.vec[i].old = *(u8 *)text_poke_addr(&text_poke_array.vec[i]); @@ -2685,7 +2687,7 @@ static void smp_text_poke_batch_process(void) } /* - * Third step: replace the first byte (int3) by the first byte of + * Third step: replace the first byte (INT3) by the first byte of the * replacing opcode. */ for (do_sync = 0, i = 0; i < text_poke_array.nr_entries; i++) {