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-rw-r--r--debian/patches-rt/0006-serial-8250-Use-port-lock-wrappers.patch465
1 files changed, 465 insertions, 0 deletions
diff --git a/debian/patches-rt/0006-serial-8250-Use-port-lock-wrappers.patch b/debian/patches-rt/0006-serial-8250-Use-port-lock-wrappers.patch
new file mode 100644
index 000000000..d6ee818bf
--- /dev/null
+++ b/debian/patches-rt/0006-serial-8250-Use-port-lock-wrappers.patch
@@ -0,0 +1,465 @@
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:43:23 +0206
+Subject: [PATCH 006/134] serial: 8250: Use port lock wrappers
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+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>
+Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
+Link: https://lore.kernel.org/r/20230914183831.587273-7-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/8250/8250_core.c | 12 ++--
+ drivers/tty/serial/8250/8250_port.c | 100 ++++++++++++++++++------------------
+ 2 files changed, 56 insertions(+), 56 deletions(-)
+
+--- a/drivers/tty/serial/8250/8250_core.c
++++ b/drivers/tty/serial/8250/8250_core.c
+@@ -259,7 +259,7 @@ static void serial8250_backup_timeout(st
+ unsigned int iir, ier = 0, lsr;
+ unsigned long flags;
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ /*
+ * Must disable interrupts or else we risk racing with the interrupt
+@@ -292,7 +292,7 @@ static void serial8250_backup_timeout(st
+ if (up->port.irq)
+ serial_out(up, UART_IER, ier);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+
+ /* Standard timer interval plus 0.2s to keep the port running */
+ mod_timer(&up->timer,
+@@ -992,11 +992,11 @@ static void serial_8250_overrun_backoff_
+ struct uart_port *port = &up->port;
+ unsigned long flags;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ up->ier |= UART_IER_RLSI | UART_IER_RDI;
+ up->port.read_status_mask |= UART_LSR_DR;
+ serial_out(up, UART_IER, up->ier);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ /**
+@@ -1194,9 +1194,9 @@ void serial8250_unregister_port(int line
+ if (uart->em485) {
+ unsigned long flags;
+
+- spin_lock_irqsave(&uart->port.lock, flags);
++ uart_port_lock_irqsave(&uart->port, &flags);
+ serial8250_em485_destroy(uart);
+- spin_unlock_irqrestore(&uart->port.lock, flags);
++ uart_port_unlock_irqrestore(&uart->port, flags);
+ }
+
+ uart_remove_one_port(&serial8250_reg, &uart->port);
+--- a/drivers/tty/serial/8250/8250_port.c
++++ b/drivers/tty/serial/8250/8250_port.c
+@@ -689,7 +689,7 @@ static void serial8250_set_sleep(struct
+
+ if (p->capabilities & UART_CAP_SLEEP) {
+ /* Synchronize UART_IER access against the console. */
+- spin_lock_irq(&p->port.lock);
++ uart_port_lock_irq(&p->port);
+ if (p->capabilities & UART_CAP_EFR) {
+ lcr = serial_in(p, UART_LCR);
+ efr = serial_in(p, UART_EFR);
+@@ -703,7 +703,7 @@ static void serial8250_set_sleep(struct
+ serial_out(p, UART_EFR, efr);
+ serial_out(p, UART_LCR, lcr);
+ }
+- spin_unlock_irq(&p->port.lock);
++ uart_port_unlock_irq(&p->port);
+ }
+
+ serial8250_rpm_put(p);
+@@ -746,9 +746,9 @@ static void enable_rsa(struct uart_8250_
+ {
+ if (up->port.type == PORT_RSA) {
+ if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
+- spin_lock_irq(&up->port.lock);
++ uart_port_lock_irq(&up->port);
+ __enable_rsa(up);
+- spin_unlock_irq(&up->port.lock);
++ uart_port_unlock_irq(&up->port);
+ }
+ if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
+ serial_out(up, UART_RSA_FRR, 0);
+@@ -768,7 +768,7 @@ static void disable_rsa(struct uart_8250
+
+ if (up->port.type == PORT_RSA &&
+ up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
+- spin_lock_irq(&up->port.lock);
++ uart_port_lock_irq(&up->port);
+
+ mode = serial_in(up, UART_RSA_MSR);
+ result = !(mode & UART_RSA_MSR_FIFO);
+@@ -781,7 +781,7 @@ static void disable_rsa(struct uart_8250
+
+ if (result)
+ up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
+- spin_unlock_irq(&up->port.lock);
++ uart_port_unlock_irq(&up->port);
+ }
+ }
+ #endif /* CONFIG_SERIAL_8250_RSA */
+@@ -1172,7 +1172,7 @@ static void autoconfig(struct uart_8250_
+ *
+ * Synchronize UART_IER access against the console.
+ */
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ up->capabilities = 0;
+ up->bugs = 0;
+@@ -1211,7 +1211,7 @@ static void autoconfig(struct uart_8250_
+ /*
+ * We failed; there's nothing here
+ */
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ DEBUG_AUTOCONF("IER test failed (%02x, %02x) ",
+ scratch2, scratch3);
+ goto out;
+@@ -1235,7 +1235,7 @@ static void autoconfig(struct uart_8250_
+ status1 = serial_in(up, UART_MSR) & UART_MSR_STATUS_BITS;
+ serial8250_out_MCR(up, save_mcr);
+ if (status1 != (UART_MSR_DCD | UART_MSR_CTS)) {
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ DEBUG_AUTOCONF("LOOP test failed (%02x) ",
+ status1);
+ goto out;
+@@ -1304,7 +1304,7 @@ static void autoconfig(struct uart_8250_
+ serial8250_clear_IER(up);
+
+ out_unlock:
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ /*
+ * Check if the device is a Fintek F81216A
+@@ -1344,9 +1344,9 @@ static void autoconfig_irq(struct uart_8
+ probe_irq_off(probe_irq_on());
+ save_mcr = serial8250_in_MCR(up);
+ /* Synchronize UART_IER access against the console. */
+- spin_lock_irq(&port->lock);
++ uart_port_lock_irq(port);
+ save_ier = serial_in(up, UART_IER);
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ serial8250_out_MCR(up, UART_MCR_OUT1 | UART_MCR_OUT2);
+
+ irqs = probe_irq_on();
+@@ -1359,9 +1359,9 @@ static void autoconfig_irq(struct uart_8
+ UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2);
+ }
+ /* Synchronize UART_IER access against the console. */
+- spin_lock_irq(&port->lock);
++ uart_port_lock_irq(port);
+ serial_out(up, UART_IER, UART_IER_ALL_INTR);
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ serial_in(up, UART_LSR);
+ serial_in(up, UART_RX);
+ serial_in(up, UART_IIR);
+@@ -1372,9 +1372,9 @@ static void autoconfig_irq(struct uart_8
+
+ serial8250_out_MCR(up, save_mcr);
+ /* Synchronize UART_IER access against the console. */
+- spin_lock_irq(&port->lock);
++ uart_port_lock_irq(port);
+ serial_out(up, UART_IER, save_ier);
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+
+ if (port->flags & UPF_FOURPORT)
+ outb_p(save_ICP, ICP);
+@@ -1442,13 +1442,13 @@ static enum hrtimer_restart serial8250_e
+ unsigned long flags;
+
+ serial8250_rpm_get(p);
+- spin_lock_irqsave(&p->port.lock, flags);
++ uart_port_lock_irqsave(&p->port, &flags);
+ if (em485->active_timer == &em485->stop_tx_timer) {
+ p->rs485_stop_tx(p);
+ em485->active_timer = NULL;
+ em485->tx_stopped = true;
+ }
+- spin_unlock_irqrestore(&p->port.lock, flags);
++ uart_port_unlock_irqrestore(&p->port, flags);
+ serial8250_rpm_put(p);
+
+ return HRTIMER_NORESTART;
+@@ -1630,12 +1630,12 @@ static enum hrtimer_restart serial8250_e
+ struct uart_8250_port *p = em485->port;
+ unsigned long flags;
+
+- spin_lock_irqsave(&p->port.lock, flags);
++ uart_port_lock_irqsave(&p->port, &flags);
+ if (em485->active_timer == &em485->start_tx_timer) {
+ __start_tx(&p->port);
+ em485->active_timer = NULL;
+ }
+- spin_unlock_irqrestore(&p->port.lock, flags);
++ uart_port_unlock_irqrestore(&p->port, flags);
+
+ return HRTIMER_NORESTART;
+ }
+@@ -1918,7 +1918,7 @@ int serial8250_handle_irq(struct uart_po
+ if (iir & UART_IIR_NO_INT)
+ return 0;
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ status = serial_lsr_in(up);
+
+@@ -1988,9 +1988,9 @@ static int serial8250_tx_threshold_handl
+ if ((iir & UART_IIR_ID) == UART_IIR_THRI) {
+ struct uart_8250_port *up = up_to_u8250p(port);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ serial8250_tx_chars(up);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ iir = serial_port_in(port, UART_IIR);
+@@ -2005,10 +2005,10 @@ static unsigned int serial8250_tx_empty(
+
+ serial8250_rpm_get(up);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
+ result = TIOCSER_TEMT;
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ serial8250_rpm_put(up);
+
+@@ -2070,13 +2070,13 @@ static void serial8250_break_ctl(struct
+ unsigned long flags;
+
+ serial8250_rpm_get(up);
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ if (break_state == -1)
+ up->lcr |= UART_LCR_SBC;
+ else
+ up->lcr &= ~UART_LCR_SBC;
+ serial_port_out(port, UART_LCR, up->lcr);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ serial8250_rpm_put(up);
+ }
+
+@@ -2211,7 +2211,7 @@ int serial8250_do_startup(struct uart_po
+ *
+ * Synchronize UART_IER access against the console.
+ */
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ up->acr = 0;
+ serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_port_out(port, UART_EFR, UART_EFR_ECB);
+@@ -2221,7 +2221,7 @@ int serial8250_do_startup(struct uart_po
+ serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_port_out(port, UART_EFR, UART_EFR_ECB);
+ serial_port_out(port, UART_LCR, 0);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ if (port->type == PORT_DA830) {
+@@ -2230,10 +2230,10 @@ int serial8250_do_startup(struct uart_po
+ *
+ * Synchronize UART_IER access against the console.
+ */
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ serial_port_out(port, UART_IER, 0);
+ serial_port_out(port, UART_DA830_PWREMU_MGMT, 0);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ mdelay(10);
+
+ /* Enable Tx, Rx and free run mode */
+@@ -2347,7 +2347,7 @@ int serial8250_do_startup(struct uart_po
+ *
+ * Synchronize UART_IER access against the console.
+ */
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ wait_for_xmitr(up, UART_LSR_THRE);
+ serial_port_out_sync(port, UART_IER, UART_IER_THRI);
+@@ -2359,7 +2359,7 @@ int serial8250_do_startup(struct uart_po
+ iir = serial_port_in(port, UART_IIR);
+ serial_port_out(port, UART_IER, 0);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ if (port->irqflags & IRQF_SHARED)
+ enable_irq(port->irq);
+@@ -2382,7 +2382,7 @@ int serial8250_do_startup(struct uart_po
+ */
+ serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ if (up->port.flags & UPF_FOURPORT) {
+ if (!up->port.irq)
+ up->port.mctrl |= TIOCM_OUT1;
+@@ -2428,7 +2428,7 @@ int serial8250_do_startup(struct uart_po
+ }
+
+ dont_test_tx_en:
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ /*
+ * Clear the interrupt registers again for luck, and clear the
+@@ -2499,17 +2499,17 @@ void serial8250_do_shutdown(struct uart_
+ *
+ * Synchronize UART_IER access against the console.
+ */
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ up->ier = 0;
+ serial_port_out(port, UART_IER, 0);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ synchronize_irq(port->irq);
+
+ if (up->dma)
+ serial8250_release_dma(up);
+
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+ if (port->flags & UPF_FOURPORT) {
+ /* reset interrupts on the AST Fourport board */
+ inb((port->iobase & 0xfe0) | 0x1f);
+@@ -2518,7 +2518,7 @@ void serial8250_do_shutdown(struct uart_
+ port->mctrl &= ~TIOCM_OUT2;
+
+ serial8250_set_mctrl(port, port->mctrl);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+
+ /*
+ * Disable break condition and FIFOs
+@@ -2754,14 +2754,14 @@ void serial8250_update_uartclk(struct ua
+ quot = serial8250_get_divisor(port, baud, &frac);
+
+ serial8250_rpm_get(up);
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ serial8250_set_divisor(port, baud, quot, frac);
+ serial_port_out(port, UART_LCR, up->lcr);
+
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ serial8250_rpm_put(up);
+
+ out_unlock:
+@@ -2798,7 +2798,7 @@ serial8250_do_set_termios(struct uart_po
+ * Synchronize UART_IER access against the console.
+ */
+ serial8250_rpm_get(up);
+- spin_lock_irqsave(&port->lock, flags);
++ uart_port_lock_irqsave(port, &flags);
+
+ up->lcr = cval; /* Save computed LCR */
+
+@@ -2901,7 +2901,7 @@ serial8250_do_set_termios(struct uart_po
+ serial_port_out(port, UART_FCR, up->fcr); /* set fcr */
+ }
+ serial8250_set_mctrl(port, port->mctrl);
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ serial8250_rpm_put(up);
+
+ /* Don't rewrite B0 */
+@@ -2924,15 +2924,15 @@ void serial8250_do_set_ldisc(struct uart
+ {
+ if (termios->c_line == N_PPS) {
+ port->flags |= UPF_HARDPPS_CD;
+- spin_lock_irq(&port->lock);
++ uart_port_lock_irq(port);
+ serial8250_enable_ms(port);
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ } else {
+ port->flags &= ~UPF_HARDPPS_CD;
+ if (!UART_ENABLE_MS(port, termios->c_cflag)) {
+- spin_lock_irq(&port->lock);
++ uart_port_lock_irq(port);
+ serial8250_disable_ms(port);
+- spin_unlock_irq(&port->lock);
++ uart_port_unlock_irq(port);
+ }
+ }
+ }
+@@ -3406,9 +3406,9 @@ void serial8250_console_write(struct uar
+ touch_nmi_watchdog();
+
+ if (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);
+
+ /*
+ * First save the IER then disable the interrupts
+@@ -3478,7 +3478,7 @@ void serial8250_console_write(struct uar
+ serial8250_modem_status(up);
+
+ if (locked)
+- spin_unlock_irqrestore(&port->lock, flags);
++ uart_port_unlock_irqrestore(port, flags);
+ }
+
+ static unsigned int probe_baud(struct uart_port *port)
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-18 03:23:33 +0000