diff options
author | Petr Mladek <pmladek@suse.com> | 2020-06-01 11:13:51 +0300 |
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committer | Petr Mladek <pmladek@suse.com> | 2020-06-01 11:13:51 +0300 |
commit | 6a0af9fc8ccef5304ef88dc7e27362732e047076 (patch) | |
tree | 000831934293ac650dfec3b382f68dffb189240f /kernel/printk | |
parent | e8cc2b97ca5aa12152c302b2f5d41d125e55ab1f (diff) | |
parent | 33225d7b0ac9903c5701bbede7dfdaeba74ad6c3 (diff) |
Merge branch 'for-5.7-preferred-console' into for-linus
Diffstat (limited to 'kernel/printk')
-rw-r--r-- | kernel/printk/console_cmdline.h | 1 | ||||
-rw-r--r-- | kernel/printk/printk.c | 122 |
2 files changed, 79 insertions, 44 deletions
diff --git a/kernel/printk/console_cmdline.h b/kernel/printk/console_cmdline.h index 11f19c466af5..3ca74ad391d6 100644 --- a/kernel/printk/console_cmdline.h +++ b/kernel/printk/console_cmdline.h @@ -6,6 +6,7 @@ struct console_cmdline { char name[16]; /* Name of the driver */ int index; /* Minor dev. to use */ + bool user_specified; /* Specified by command line vs. platform */ char *options; /* Options for the driver */ #ifdef CONFIG_A11Y_BRAILLE_CONSOLE char *brl_options; /* Options for braille driver */ diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index a44094727a5c..c59d9a1567ad 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -280,6 +280,7 @@ static struct console *exclusive_console; static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES]; static int preferred_console = -1; +static bool has_preferred_console; int console_set_on_cmdline; EXPORT_SYMBOL(console_set_on_cmdline); @@ -2115,7 +2116,7 @@ asmlinkage __visible void early_printk(const char *fmt, ...) #endif static int __add_preferred_console(char *name, int idx, char *options, - char *brl_options) + char *brl_options, bool user_specified) { struct console_cmdline *c; int i; @@ -2130,6 +2131,8 @@ static int __add_preferred_console(char *name, int idx, char *options, if (strcmp(c->name, name) == 0 && c->index == idx) { if (!brl_options) preferred_console = i; + if (user_specified) + c->user_specified = true; return 0; } } @@ -2139,6 +2142,7 @@ static int __add_preferred_console(char *name, int idx, char *options, preferred_console = i; strlcpy(c->name, name, sizeof(c->name)); c->options = options; + c->user_specified = user_specified; braille_set_options(c, brl_options); c->index = idx; @@ -2193,7 +2197,7 @@ static int __init console_setup(char *str) idx = simple_strtoul(s, NULL, 10); *s = 0; - __add_preferred_console(buf, idx, options, brl_options); + __add_preferred_console(buf, idx, options, brl_options, true); console_set_on_cmdline = 1; return 1; } @@ -2214,7 +2218,7 @@ __setup("console=", console_setup); */ int add_preferred_console(char *name, int idx, char *options) { - return __add_preferred_console(name, idx, options, NULL); + return __add_preferred_console(name, idx, options, NULL, false); } bool console_suspend_enabled = true; @@ -2627,6 +2631,63 @@ static int __init keep_bootcon_setup(char *str) early_param("keep_bootcon", keep_bootcon_setup); /* + * This is called by register_console() to try to match + * the newly registered console with any of the ones selected + * by either the command line or add_preferred_console() and + * setup/enable it. + * + * Care need to be taken with consoles that are statically + * enabled such as netconsole + */ +static int try_enable_new_console(struct console *newcon, bool user_specified) +{ + struct console_cmdline *c; + int i; + + for (i = 0, c = console_cmdline; + i < MAX_CMDLINECONSOLES && c->name[0]; + i++, c++) { + if (c->user_specified != user_specified) + continue; + if (!newcon->match || + newcon->match(newcon, c->name, c->index, c->options) != 0) { + /* default matching */ + BUILD_BUG_ON(sizeof(c->name) != sizeof(newcon->name)); + if (strcmp(c->name, newcon->name) != 0) + continue; + if (newcon->index >= 0 && + newcon->index != c->index) + continue; + if (newcon->index < 0) + newcon->index = c->index; + + if (_braille_register_console(newcon, c)) + return 0; + + if (newcon->setup && + newcon->setup(newcon, c->options) != 0) + return -EIO; + } + newcon->flags |= CON_ENABLED; + if (i == preferred_console) { + newcon->flags |= CON_CONSDEV; + has_preferred_console = true; + } + return 0; + } + + /* + * Some consoles, such as pstore and netconsole, can be enabled even + * without matching. Accept the pre-enabled consoles only when match() + * and setup() had a change to be called. + */ + if (newcon->flags & CON_ENABLED && c->user_specified == user_specified) + return 0; + + return -ENOENT; +} + +/* * The console driver calls this routine during kernel initialization * to register the console printing procedure with printk() and to * print any messages that were printed by the kernel before the @@ -2647,11 +2708,9 @@ early_param("keep_bootcon", keep_bootcon_setup); */ void register_console(struct console *newcon) { - int i; unsigned long flags; struct console *bcon = NULL; - struct console_cmdline *c; - static bool has_preferred; + int err; if (console_drivers) for_each_console(bcon) @@ -2678,15 +2737,15 @@ void register_console(struct console *newcon) if (console_drivers && console_drivers->flags & CON_BOOT) bcon = console_drivers; - if (!has_preferred || bcon || !console_drivers) - has_preferred = preferred_console >= 0; + if (!has_preferred_console || bcon || !console_drivers) + has_preferred_console = preferred_console >= 0; /* * See if we want to use this console driver. If we * didn't select a console we take the first one * that registers here. */ - if (!has_preferred) { + if (!has_preferred_console) { if (newcon->index < 0) newcon->index = 0; if (newcon->setup == NULL || @@ -2694,47 +2753,20 @@ void register_console(struct console *newcon) newcon->flags |= CON_ENABLED; if (newcon->device) { newcon->flags |= CON_CONSDEV; - has_preferred = true; + has_preferred_console = true; } } } - /* - * See if this console matches one we selected on - * the command line. - */ - for (i = 0, c = console_cmdline; - i < MAX_CMDLINECONSOLES && c->name[0]; - i++, c++) { - if (!newcon->match || - newcon->match(newcon, c->name, c->index, c->options) != 0) { - /* default matching */ - BUILD_BUG_ON(sizeof(c->name) != sizeof(newcon->name)); - if (strcmp(c->name, newcon->name) != 0) - continue; - if (newcon->index >= 0 && - newcon->index != c->index) - continue; - if (newcon->index < 0) - newcon->index = c->index; - - if (_braille_register_console(newcon, c)) - return; - - if (newcon->setup && - newcon->setup(newcon, c->options) != 0) - break; - } + /* See if this console matches one we selected on the command line */ + err = try_enable_new_console(newcon, true); - newcon->flags |= CON_ENABLED; - if (i == preferred_console) { - newcon->flags |= CON_CONSDEV; - has_preferred = true; - } - break; - } + /* If not, try to match against the platform default(s) */ + if (err == -ENOENT) + err = try_enable_new_console(newcon, false); - if (!(newcon->flags & CON_ENABLED)) + /* printk() messages are not printed to the Braille console. */ + if (err || newcon->flags & CON_BRL) return; /* @@ -2756,6 +2788,8 @@ void register_console(struct console *newcon) console_drivers = newcon; if (newcon->next) newcon->next->flags &= ~CON_CONSDEV; + /* Ensure this flag is always set for the head of the list */ + newcon->flags |= CON_CONSDEV; } else { newcon->next = console_drivers->next; console_drivers->next = newcon; |