diff options
Diffstat (limited to 'drivers/tty/sysrq.c')
| -rw-r--r-- | drivers/tty/sysrq.c | 72 |
1 files changed, 55 insertions, 17 deletions
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index e5974b8239c9..1f78b0db3b25 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -452,7 +452,7 @@ static const struct sysrq_key_op sysrq_unrt_op = { static void sysrq_handle_replay_logs(u8 key) { - console_replay_all(); + console_try_replay_all(); } static struct sysrq_key_op sysrq_replay_logs_op = { .handler = sysrq_handle_replay_logs, @@ -531,6 +531,7 @@ static const struct sysrq_key_op *sysrq_key_table[62] = { NULL, /* P */ NULL, /* Q */ &sysrq_replay_logs_op, /* R */ + /* S: May be registered by sched_ext for resetting */ NULL, /* S */ NULL, /* T */ NULL, /* U */ @@ -582,7 +583,6 @@ static void __sysrq_put_key_op(u8 key, const struct sysrq_key_op *op_p) void __handle_sysrq(u8 key, bool check_mask) { const struct sysrq_key_op *op_p; - int orig_log_level; int orig_suppress_printk; int i; @@ -592,13 +592,12 @@ void __handle_sysrq(u8 key, bool check_mask) rcu_sysrq_start(); rcu_read_lock(); /* - * Raise the apparent loglevel to maximum so that the sysrq header - * is shown to provide the user with positive feedback. We do not - * simply emit this at KERN_EMERG as that would change message - * routing in the consumers of /proc/kmsg. + * Enter in the force_console context so that sysrq header is shown to + * provide the user with positive feedback. We do not simply emit this + * at KERN_EMERG as that would change message routing in the consumers + * of /proc/kmsg. */ - orig_log_level = console_loglevel; - console_loglevel = CONSOLE_LOGLEVEL_DEFAULT; + printk_force_console_enter(); op_p = __sysrq_get_key_op(key); if (op_p) { @@ -608,11 +607,11 @@ void __handle_sysrq(u8 key, bool check_mask) */ if (!check_mask || sysrq_on_mask(op_p->enable_mask)) { pr_info("%s\n", op_p->action_msg); - console_loglevel = orig_log_level; + printk_force_console_exit(); op_p->handler(key); } else { pr_info("This sysrq operation is disabled.\n"); - console_loglevel = orig_log_level; + printk_force_console_exit(); } } else { pr_info("HELP : "); @@ -630,7 +629,7 @@ void __handle_sysrq(u8 key, bool check_mask) } } pr_cont("\n"); - console_loglevel = orig_log_level; + printk_force_console_exit(); } rcu_read_unlock(); rcu_sysrq_end(); @@ -713,7 +712,8 @@ static void sysrq_parse_reset_sequence(struct sysrq_state *state) static void sysrq_do_reset(struct timer_list *t) { - struct sysrq_state *state = from_timer(state, t, keyreset_timer); + struct sysrq_state *state = timer_container_of(state, t, + keyreset_timer); state->reset_requested = true; @@ -744,7 +744,7 @@ static void sysrq_detect_reset_sequence(struct sysrq_state *state, */ if (value && state->reset_seq_cnt) { state->reset_canceled = true; - del_timer(&state->keyreset_timer); + timer_delete(&state->keyreset_timer); } } else if (value == 0) { /* @@ -752,7 +752,7 @@ static void sysrq_detect_reset_sequence(struct sysrq_state *state, * to be pressed and held for the reset timeout * to hold. */ - del_timer(&state->keyreset_timer); + timer_delete(&state->keyreset_timer); if (--state->reset_seq_cnt == 0) state->reset_canceled = false; @@ -770,8 +770,6 @@ static void sysrq_of_get_keyreset_config(void) { u32 key; struct device_node *np; - struct property *prop; - const __be32 *p; np = of_find_node_by_path("/chosen/linux,sysrq-reset-seq"); if (!np) { @@ -782,7 +780,7 @@ static void sysrq_of_get_keyreset_config(void) /* Reset in case a __weak definition was present */ sysrq_reset_seq_len = 0; - of_property_for_each_u32(np, "keyset", prop, p, key) { + of_property_for_each_u32(np, "keyset", key) { if (key == KEY_RESERVED || key > KEY_MAX || sysrq_reset_seq_len == SYSRQ_KEY_RESET_MAX) break; @@ -1122,6 +1120,46 @@ int sysrq_toggle_support(int enable_mask) } EXPORT_SYMBOL_GPL(sysrq_toggle_support); +static int sysrq_sysctl_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + int tmp, ret; + struct ctl_table t = *table; + + tmp = sysrq_mask(); + t.data = &tmp; + + /* + * Behaves like do_proc_dointvec as t does not have min nor max. + */ + ret = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); + if (ret) + return ret; + + if (write) + sysrq_toggle_support(tmp); + + return 0; +} + +static const struct ctl_table sysrq_sysctl_table[] = { + { + .procname = "sysrq", + .data = NULL, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = sysrq_sysctl_handler, + }, +}; + +static int __init init_sysrq_sysctl(void) +{ + register_sysctl_init("kernel", sysrq_sysctl_table); + return 0; +} + +subsys_initcall(init_sysrq_sysctl); + static int __sysrq_swap_key_ops(u8 key, const struct sysrq_key_op *insert_op_p, const struct sysrq_key_op *remove_op_p) { |