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Diffstat (limited to '')
| -rw-r--r-- | debian/patches-rt/0065-serial-sunhv-Use-port-lock-wrappers.patch | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/debian/patches-rt/0065-serial-sunhv-Use-port-lock-wrappers.patch b/debian/patches-rt/0065-serial-sunhv-Use-port-lock-wrappers.patch new file mode 100644 index 000000000..beacd2be7 --- /dev/null +++ b/debian/patches-rt/0065-serial-sunhv-Use-port-lock-wrappers.patch @@ -0,0 +1,149 @@ +From: Thomas Gleixner <tglx@linutronix.de> +Date: Thu, 14 Sep 2023 20:44:22 +0206 +Subject: [PATCH 065/134] serial: sunhv: Use port lock wrappers +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.6/older/patches-6.6.7-rt18.tar.xz + +When a serial port is used for kernel console output, then all +modifications to the UART registers which are done from other contexts, +e.g. getty, termios, are interference points for the kernel console. + +So far this has been ignored and the printk output is based on the +principle of hope. The rework of the console infrastructure which aims to +support threaded and atomic consoles, requires to mark sections which +modify the UART registers as unsafe. This allows the atomic write function +to make informed decisions and eventually to restore operational state. It +also allows to prevent the regular UART code from modifying UART registers +while printk output is in progress. + +All modifications of UART registers are guarded by the UART port lock, +which provides an obvious synchronization point with the console +infrastructure. + +To avoid adding this functionality to all UART drivers, wrap the +spin_[un]lock*() invocations for uart_port::lock into helper functions +which just contain the spin_[un]lock*() invocations for now. In a +subsequent step these helpers will gain the console synchronization +mechanisms. + +Converted with coccinelle. No functional change. + +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +Signed-off-by: John Ogness <john.ogness@linutronix.de> +Link: https://lore.kernel.org/r/20230914183831.587273-66-john.ogness@linutronix.de +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + drivers/tty/serial/sunhv.c | 28 ++++++++++++++-------------- + 1 file changed, 14 insertions(+), 14 deletions(-) + +--- a/drivers/tty/serial/sunhv.c ++++ b/drivers/tty/serial/sunhv.c +@@ -217,10 +217,10 @@ static irqreturn_t sunhv_interrupt(int i + struct tty_port *tport; + unsigned long flags; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + tport = receive_chars(port); + transmit_chars(port); +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + + if (tport) + tty_flip_buffer_push(tport); +@@ -271,7 +271,7 @@ static void sunhv_send_xchar(struct uart + if (ch == __DISABLED_CHAR) + return; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + while (limit-- > 0) { + long status = sun4v_con_putchar(ch); +@@ -280,7 +280,7 @@ static void sunhv_send_xchar(struct uart + udelay(1); + } + +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + + /* port->lock held by caller. */ +@@ -295,7 +295,7 @@ static void sunhv_break_ctl(struct uart_ + unsigned long flags; + int limit = 10000; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + while (limit-- > 0) { + long status = sun4v_con_putchar(CON_BREAK); +@@ -304,7 +304,7 @@ static void sunhv_break_ctl(struct uart_ + udelay(1); + } + +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + } + +@@ -328,7 +328,7 @@ static void sunhv_set_termios(struct uar + unsigned int iflag, cflag; + unsigned long flags; + +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + iflag = termios->c_iflag; + cflag = termios->c_cflag; +@@ -343,7 +343,7 @@ static void sunhv_set_termios(struct uar + uart_update_timeout(port, cflag, + (port->uartclk / (16 * quot))); + +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + + static const char *sunhv_type(struct uart_port *port) +@@ -437,9 +437,9 @@ static void sunhv_console_write_paged(st + int locked = 1; + + if (port->sysrq || oops_in_progress) +- locked = spin_trylock_irqsave(&port->lock, flags); ++ locked = uart_port_trylock_irqsave(port, &flags); + else +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + while (n > 0) { + unsigned long ra = __pa(con_write_page); +@@ -470,7 +470,7 @@ static void sunhv_console_write_paged(st + } + + if (locked) +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + + static inline void sunhv_console_putchar(struct uart_port *port, char c) +@@ -492,9 +492,9 @@ static void sunhv_console_write_bychar(s + int i, locked = 1; + + if (port->sysrq || oops_in_progress) +- locked = spin_trylock_irqsave(&port->lock, flags); ++ locked = uart_port_trylock_irqsave(port, &flags); + else +- spin_lock_irqsave(&port->lock, flags); ++ uart_port_lock_irqsave(port, &flags); + + for (i = 0; i < n; i++) { + if (*s == '\n') +@@ -503,7 +503,7 @@ static void sunhv_console_write_bychar(s + } + + if (locked) +- spin_unlock_irqrestore(&port->lock, flags); ++ uart_port_unlock_irqrestore(port, flags); + } + + static struct console sunhv_console = { |