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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:28:00 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:28:00 +0000
commit3565071f226432336a54d0193d729fa4508a3394 (patch)
tree4cde13f078f84c0a7785d234fd52edce7c90546a /debian/patches-rt/0067-serial-sunsab-Use-port-lock-wrappers.patch
parentAdding upstream version 6.6.15. (diff)
downloadlinux-3565071f226432336a54d0193d729fa4508a3394.tar.xz
linux-3565071f226432336a54d0193d729fa4508a3394.zip
Adding debian version 6.6.15-2.debian/6.6.15-2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'debian/patches-rt/0067-serial-sunsab-Use-port-lock-wrappers.patch')
-rw-r--r--debian/patches-rt/0067-serial-sunsab-Use-port-lock-wrappers.patch176
1 files changed, 176 insertions, 0 deletions
diff --git a/debian/patches-rt/0067-serial-sunsab-Use-port-lock-wrappers.patch b/debian/patches-rt/0067-serial-sunsab-Use-port-lock-wrappers.patch
new file mode 100644
index 0000000000..b96d5080cd
--- /dev/null
+++ b/debian/patches-rt/0067-serial-sunsab-Use-port-lock-wrappers.patch
@@ -0,0 +1,176 @@
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Thu, 14 Sep 2023 20:44:24 +0206
+Subject: [PATCH 067/134] serial: sunsab: 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/20230914183831.587273-68-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/sunsab.c | 34 +++++++++++++++++-----------------
+ 1 file changed, 17 insertions(+), 17 deletions(-)
+
+--- a/drivers/tty/serial/sunsab.c
++++ b/drivers/tty/serial/sunsab.c
+@@ -310,7 +310,7 @@ static irqreturn_t sunsab_interrupt(int
+ unsigned long flags;
+ unsigned char gis;
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ status.stat = 0;
+ gis = readb(&up->regs->r.gis) >> up->gis_shift;
+@@ -331,7 +331,7 @@ static irqreturn_t sunsab_interrupt(int
+ transmit_chars(up, &status);
+ }
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+
+ if (port)
+ tty_flip_buffer_push(port);
+@@ -473,12 +473,12 @@ static void sunsab_send_xchar(struct uar
+ if (ch == __DISABLED_CHAR)
+ return;
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ sunsab_tec_wait(up);
+ writeb(ch, &up->regs->w.tic);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ }
+
+ /* port->lock held by caller. */
+@@ -499,7 +499,7 @@ static void sunsab_break_ctl(struct uart
+ unsigned long flags;
+ unsigned char val;
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ val = up->cached_dafo;
+ if (break_state)
+@@ -512,7 +512,7 @@ static void sunsab_break_ctl(struct uart
+ if (test_bit(SAB82532_XPR, &up->irqflags))
+ sunsab_tx_idle(up);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ }
+
+ /* port->lock is not held. */
+@@ -527,7 +527,7 @@ static int sunsab_startup(struct uart_po
+ if (err)
+ return err;
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ /*
+ * Wait for any commands or immediate characters
+@@ -582,7 +582,7 @@ static int sunsab_startup(struct uart_po
+ set_bit(SAB82532_ALLS, &up->irqflags);
+ set_bit(SAB82532_XPR, &up->irqflags);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+
+ return 0;
+ }
+@@ -594,7 +594,7 @@ static void sunsab_shutdown(struct uart_
+ container_of(port, struct uart_sunsab_port, port);
+ unsigned long flags;
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ /* Disable Interrupts */
+ up->interrupt_mask0 = 0xff;
+@@ -628,7 +628,7 @@ static void sunsab_shutdown(struct uart_
+ writeb(tmp, &up->regs->rw.ccr0);
+ #endif
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ free_irq(up->port.irq, up);
+ }
+
+@@ -779,9 +779,9 @@ static void sunsab_set_termios(struct ua
+ unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
+ unsigned int quot = uart_get_divisor(port, baud);
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+ sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ }
+
+ static const char *sunsab_type(struct uart_port *port)
+@@ -857,15 +857,15 @@ static void sunsab_console_write(struct
+ int locked = 1;
+
+ if (up->port.sysrq || oops_in_progress)
+- locked = spin_trylock_irqsave(&up->port.lock, flags);
++ locked = uart_port_trylock_irqsave(&up->port, &flags);
+ else
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ uart_console_write(&up->port, s, n, sunsab_console_putchar);
+ sunsab_tec_wait(up);
+
+ if (locked)
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+ }
+
+ static int sunsab_console_setup(struct console *con, char *options)
+@@ -914,7 +914,7 @@ static int sunsab_console_setup(struct c
+ */
+ sunsab_startup(&up->port);
+
+- spin_lock_irqsave(&up->port.lock, flags);
++ uart_port_lock_irqsave(&up->port, &flags);
+
+ /*
+ * Finally, enable interrupts
+@@ -932,7 +932,7 @@ static int sunsab_console_setup(struct c
+ sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
+ sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
+
+- spin_unlock_irqrestore(&up->port.lock, flags);
++ uart_port_unlock_irqrestore(&up->port, flags);
+
+ return 0;
+ }