Commit 21493c6e authored by Petr Mladek's avatar Petr Mladek

Merge branch 'rework/console-list-lock' into for-linus

parents 98d0052d 4fe59a13
......@@ -171,6 +171,7 @@ static int configure_kgdboc(void)
int err = -ENODEV;
char *cptr = config;
struct console *cons;
int cookie;
if (!strlen(config) || isspace(config[0])) {
err = 0;
......@@ -189,20 +190,9 @@ static int configure_kgdboc(void)
if (kgdboc_register_kbd(&cptr))
goto do_register;
/*
* tty_find_polling_driver() can call uart_set_options()
* (via poll_init) to configure the uart. Take the console_list_lock
* in order to synchronize against register_console(), which can also
* configure the uart via uart_set_options(). This also allows safe
* traversal of the console list.
*/
console_list_lock();
p = tty_find_polling_driver(cptr, &tty_line);
if (!p) {
console_list_unlock();
if (!p)
goto noconfig;
}
/*
* Take console_lock to serialize device() callback with
......@@ -211,7 +201,8 @@ static int configure_kgdboc(void)
*/
console_lock();
for_each_console(cons) {
cookie = console_srcu_read_lock();
for_each_console_srcu(cons) {
int idx;
if (cons->device && cons->device(cons, &idx) == p &&
idx == tty_line) {
......@@ -219,11 +210,10 @@ static int configure_kgdboc(void)
break;
}
}
console_srcu_read_unlock(cookie);
console_unlock();
console_list_unlock();
kgdb_tty_driver = p;
kgdb_tty_line = tty_line;
......
......@@ -2212,6 +2212,9 @@ EXPORT_SYMBOL_GPL(uart_parse_options);
* @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
* @bits: number of data bits
* @flow: flow control character - 'r' (rts)
*
* Locking: Caller must hold console_list_lock in order to serialize
* early initialization of the serial-console lock.
*/
int
uart_set_options(struct uart_port *port, struct console *co,
......@@ -2619,7 +2622,9 @@ static int uart_poll_init(struct tty_driver *driver, int line, char *options)
if (!ret && options) {
uart_parse_options(options, &baud, &parity, &bits, &flow);
console_list_lock();
ret = uart_set_options(port, NULL, baud, parity, bits, flow);
console_list_unlock();
}
out:
mutex_unlock(&tport->mutex);
......
......@@ -123,6 +123,7 @@ bool console_srcu_read_lock_is_held(void)
{
return srcu_read_lock_held(&console_srcu);
}
EXPORT_SYMBOL(console_srcu_read_lock_is_held);
#endif
enum devkmsg_log_bits {
......@@ -1891,6 +1892,7 @@ static void console_lock_spinning_enable(void)
/**
* console_lock_spinning_disable_and_check - mark end of code where another
* thread was able to busy wait and check if there is a waiter
* @cookie: cookie returned from console_srcu_read_lock()
*
* This is called at the end of the section where spinning is allowed.
* It has two functions. First, it is a signal that it is no longer
......
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