3.0-stable patches

added patches:
	pch_uart-fix-a-deadlock-when-pch_uart-as-console.patch

diff --git a/queue-3.0/pch_uart-fix-a-deadlock-when-pch_uart-as-console.patch b/queue-3.0/pch_uart-fix-a-deadlock-when-pch_uart-as-console.patch
new file mode 100644 (file)
index 0000000..b17cbe7
--- /dev/null
+++ b/queue-3.0/pch_uart-fix-a-deadlock-when-pch_uart-as-console.patch
@@ -0,0 +1,81 @@
+From 384e301e3519599b000c1a2ecd938b533fc15d85 Mon Sep 17 00:00:00 2001
+From: Liang Li <liang.li@windriver.com>
+Date: Sat, 19 Jan 2013 17:52:10 +0800
+Subject: pch_uart: fix a deadlock when pch_uart as console
+
+From: Liang Li <liang.li@windriver.com>
+
+commit 384e301e3519599b000c1a2ecd938b533fc15d85 upstream.
+
+When we use pch_uart as system console like 'console=ttyPCH0,115200',
+then 'send break' to it. We'll encounter the deadlock on a cpu/core,
+with interrupts disabled on the core. When we happen to have all irqs
+affinity to cpu0 then the deadlock on cpu0 actually deadlock whole
+system.
+
+In pch_uart_interrupt, we have spin_lock_irqsave(&priv->lock, flags)
+then call pch_uart_err_ir when break is received. Then the call to
+dev_err would actually call to pch_console_write then we'll run into
+another spin_lock(&priv->lock), with interrupts disabled.
+
+So in the call sequence lead by pch_uart_interrupt, we should be
+carefully to call functions that will 'print message to console' only
+in case the uart port is not being used as serial console.
+
+Signed-off-by: Liang Li <liang.li@windriver.com>
+Cc: Yijing Wang <wangyijing@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/serial/pch_uart.c |   33 ++++++++++++++++++++++++---------
+ 1 file changed, 24 insertions(+), 9 deletions(-)
+
+--- a/drivers/tty/serial/pch_uart.c
++++ b/drivers/tty/serial/pch_uart.c
+@@ -935,22 +935,37 @@ static unsigned int dma_handle_tx(struct
+ static void pch_uart_err_ir(struct eg20t_port *priv, unsigned int lsr)
+ {
+       u8 fcr = ioread8(priv->membase + UART_FCR);
++      struct uart_port *port = &priv->port;
++      struct tty_struct *tty = tty_port_tty_get(&port->state->port);
++      char   *error_msg[5] = {};
++      int    i = 0;
+ 
+       /* Reset FIFO */
+       fcr |= UART_FCR_CLEAR_RCVR;
+       iowrite8(fcr, priv->membase + UART_FCR);
+ 
+       if (lsr & PCH_UART_LSR_ERR)
+-              dev_err(&priv->pdev->dev, "Error data in FIFO\n");
++              error_msg[i++] = "Error data in FIFO\n";
+ 
+-      if (lsr & UART_LSR_FE)
+-              dev_err(&priv->pdev->dev, "Framing Error\n");
+-
+-      if (lsr & UART_LSR_PE)
+-              dev_err(&priv->pdev->dev, "Parity Error\n");
+-
+-      if (lsr & UART_LSR_OE)
+-              dev_err(&priv->pdev->dev, "Overrun Error\n");
++      if (lsr & UART_LSR_FE) {
++              port->icount.frame++;
++              error_msg[i++] = "  Framing Error\n";
++      }
++
++      if (lsr & UART_LSR_PE) {
++              port->icount.parity++;
++              error_msg[i++] = "  Parity Error\n";
++      }
++
++      if (lsr & UART_LSR_OE) {
++              port->icount.overrun++;
++              error_msg[i++] = "  Overrun Error\n";
++      }
++
++      if (tty == NULL) {
++              for (i = 0; error_msg[i] != NULL; i++)
++                      dev_err(&priv->pdev->dev, error_msg[i]);
++      }
+ }
+ 
+ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)

diff --git a/queue-3.0/series b/queue-3.0/series
index 608723c1820b6ae8902d9f9413628db37e49bda5..398cc97f0270a957116270c2455cc75ba24fe0f1 100644 (file)
--- a/queue-3.0/series
+++ b/queue-3.0/series
@@ -5,3 +5,4 @@ dlci-validate-the-net-device-in-dlci_del.patch
 perf-disable-monitoring-on-setuid-processes-for-regular-users.patch
 ubifs-prepare-to-fix-a-horrid-bug.patch
 ubifs-fix-a-horrid-bug.patch
+pch_uart-fix-a-deadlock-when-pch_uart-as-console.patch