4.19-stable patches

added patches:
	serial-uartps-move-the-spinlock-after-the-read-of-the-tx-empty.patch

diff --git a/queue-4.19/serial-uartps-move-the-spinlock-after-the-read-of-the-tx-empty.patch b/queue-4.19/serial-uartps-move-the-spinlock-after-the-read-of-the-tx-empty.patch
new file mode 100644 (file)
index 0000000..07f7070
--- /dev/null
+++ b/queue-4.19/serial-uartps-move-the-spinlock-after-the-read-of-the-tx-empty.patch
@@ -0,0 +1,40 @@
+From 107475685abfdee504bb0ef4824f15797f6d2d4d Mon Sep 17 00:00:00 2001
+From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
+Date: Fri, 24 May 2019 14:41:28 +0530
+Subject: serial: uartps: Move the spinlock after the read of the tx empty
+
+From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
+
+commit 107475685abfdee504bb0ef4824f15797f6d2d4d upstream.
+
+Currently we are doing a read of the status register.
+Move the spinlock after that as the reads need not be spinlock
+protected. This patch prevents relaxing the cpu with spinlock held.
+
+Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
+Cc: Pavel Machek <pavel@denx.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/tty/serial/xilinx_uartps.c |    3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+--- a/drivers/tty/serial/xilinx_uartps.c
++++ b/drivers/tty/serial/xilinx_uartps.c
+@@ -686,8 +686,6 @@ static void cdns_uart_set_termios(struct
+       unsigned int ctrl_reg, mode_reg, val;
+       int err;
+ 
+-      spin_lock_irqsave(&port->lock, flags);
+-
+       /* Wait for the transmit FIFO to empty before making changes */
+       if (!(readl(port->membase + CDNS_UART_CR) &
+                               CDNS_UART_CR_TX_DIS)) {
+@@ -699,6 +697,7 @@ static void cdns_uart_set_termios(struct
+                       return;
+               }
+       }
++      spin_lock_irqsave(&port->lock, flags);
+ 
+       /* Disable the TX and RX to set baud rate */
+       ctrl_reg = readl(port->membase + CDNS_UART_CR);

diff --git a/queue-4.19/series b/queue-4.19/series
index a3d39e1177744a1d58404a8e6121599f1eaf1217..8fc9ee4cf12fc2fa993b4fbd78798e5b5c467c54 100644 (file)
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -50,3 +50,4 @@ libertas-make-lbs_ibss_join_existing-return-error-co.patch
 scsi-megaraid_sas-do-not-initiate-ocr-if-controller-is-not-in-ready-state.patch
 x86-stackframe-move-encode_frame_pointer-to-asm-frame.h.patch
 x86-stackframe-x86-ftrace-add-pt_regs-frame-annotations.patch
+serial-uartps-move-the-spinlock-after-the-read-of-the-tx-empty.patch