From 61c0e37950b88bad590056286c1d766b1f167f4e Mon Sep 17 00:00:00 2001 From: Jorge Ramirez-Ortiz Date: Mon, 20 May 2019 20:38:48 +0200 Subject: [PATCH 1/5] tty: serial: msm_serial: Fix XON/XOFF When the tty layer requests the uart to throttle, the current code executing in msm_serial will trigger "Bad mode in Error Handler" and generate an invalid stack frame in pstore before rebooting (that is if pstore is indeed configured: otherwise the user shall just notice a reboot with no further information dumped to the console). This patch replaces the PIO byte accessor with the word accessor already used in PIO mode. Fixes: 68252424a7c7 ("tty: serial: msm: Support big-endian CPUs") Cc: stable@vger.kernel.org Signed-off-by: Jorge Ramirez-Ortiz Reviewed-by: Bjorn Andersson Reviewed-by: Stephen Boyd Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/msm_serial.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c index 109096033bb1..23833ad952ba 100644 --- a/drivers/tty/serial/msm_serial.c +++ b/drivers/tty/serial/msm_serial.c @@ -860,6 +860,7 @@ static void msm_handle_tx(struct uart_port *port) struct circ_buf *xmit = &msm_port->uart.state->xmit; struct msm_dma *dma = &msm_port->tx_dma; unsigned int pio_count, dma_count, dma_min; + char buf[4] = { 0 }; void __iomem *tf; int err = 0; @@ -869,10 +870,12 @@ static void msm_handle_tx(struct uart_port *port) else tf = port->membase + UART_TF; + buf[0] = port->x_char; + if (msm_port->is_uartdm) msm_reset_dm_count(port, 1); - iowrite8_rep(tf, &port->x_char, 1); + iowrite32_rep(tf, buf, 1); port->icount.tx++; port->x_char = 0; return; From 8178eeb3e8007d29b1e9dfd3c4d0f90de0f6ce55 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Fri, 17 May 2019 12:01:38 +0200 Subject: [PATCH 2/5] serial: imx: remove log spamming error message Each time the DMA engine signals a transaction error the driver prints a message at error level. Getting transaction errors is pretty much expected on baudrate mismatches and the correspoding error counters are increased in this case properly. Remove the error message which is possibly repeated at a very high rate which can lock up the whole system. Signed-off-by: Sascha Hauer Reviewed-by: Fabio Estevam Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index dff75dc94731..8b752e895053 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1165,7 +1165,6 @@ static void imx_uart_clear_rx_errors(struct imx_port *sport) sport->port.icount.buf_overrun++; tty_flip_buffer_push(port); } else { - dev_err(sport->port.dev, "DMA transaction error.\n"); if (usr1 & USR1_FRAMERR) { sport->port.icount.frame++; imx_uart_writel(sport, USR1_FRAMERR, USR1); From 099506cbbc79c0bd52b19cb6b930f256dabc3950 Mon Sep 17 00:00:00 2001 From: "George G. Davis" Date: Tue, 14 May 2019 23:29:34 -0400 Subject: [PATCH 3/5] serial: sh-sci: disable DMA for uart_console As noted in commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for console UART"), UART console lines use low-level PIO only access functions which will conflict with use of the line when DMA is enabled, e.g. when the console line is also used for systemd messages. So disable DMA support for UART console lines. Reported-by: Michael Rodin Link: https://patchwork.kernel.org/patch/10929511/ Tested-by: Eugeniu Rosca Reviewed-by: Simon Horman Reviewed-by: Wolfram Sang Reviewed-by: Geert Uytterhoeven Cc: stable@vger.kernel.org Signed-off-by: George G. Davis Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sh-sci.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 3cd139752d3f..abc705716aa0 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1557,6 +1557,13 @@ static void sci_request_dma(struct uart_port *port) dev_dbg(port->dev, "%s: port %d\n", __func__, port->line); + /* + * DMA on console may interfere with Kernel log messages which use + * plain putchar(). So, simply don't use it with a console. + */ + if (uart_console(port)) + return; + if (!port->dev->of_node) return; From 5d24f455c182d5116dd5db8e1dc501115ecc9c2c Mon Sep 17 00:00:00 2001 From: Joe Burmeister Date: Mon, 13 May 2019 11:23:57 +0100 Subject: [PATCH 4/5] tty: max310x: Fix external crystal register setup The datasheet states: Bit 4: ClockEnSet the ClockEn bit high to enable an external clocking (crystal or clock generator at XIN). Set the ClockEn bit to 0 to disable clocking Bit 1: CrystalEnSet the CrystalEn bit high to enable the crystal oscillator. When using an external clock source at XIN, CrystalEn must be set low. The bit 4, MAX310X_CLKSRC_EXTCLK_BIT, should be set and was not. This was required to make the MAX3107 with an external crystal on our board able to send or receive data. Signed-off-by: Joe Burmeister Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/max310x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index 450ba6d7996c..e5aebbf5f302 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -581,7 +581,7 @@ static int max310x_set_ref_clk(struct device *dev, struct max310x_port *s, } /* Configure clock source */ - clksrc = xtal ? MAX310X_CLKSRC_CRYST_BIT : MAX310X_CLKSRC_EXTCLK_BIT; + clksrc = MAX310X_CLKSRC_EXTCLK_BIT | (xtal ? MAX310X_CLKSRC_CRYST_BIT : 0); /* Configure PLL */ if (pllcfg) { From a1ad1cc9704f64c169261a76e1aee1cf1ae51832 Mon Sep 17 00:00:00 2001 From: Grzegorz Halat Date: Fri, 26 Apr 2019 16:59:46 +0200 Subject: [PATCH 5/5] vt/fbcon: deinitialize resources in visual_init() after failed memory allocation After memory allocation failure vc_allocate() doesn't clean up data which has been initialized in visual_init(). In case of fbcon this leads to divide-by-0 in fbcon_init() on next open of the same tty. memory allocation in vc_allocate() may fail here: 1097: vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL); on next open() fbcon_init() skips vc_font.data initialization: 1088: if (!p->fontdata) { division by zero in fbcon_init() happens here: 1149: new_cols /= vc->vc_font.width; Additional check is needed in fbcon_deinit() to prevent usage of uninitialized vc_screenbuf: 1251: if (vc->vc_hi_font_mask && vc->vc_screenbuf) 1252: set_vc_hi_font(vc, false); Crash: #6 [ffffc90001eafa60] divide_error at ffffffff81a00be4 [exception RIP: fbcon_init+463] RIP: ffffffff814b860f RSP: ffffc90001eafb18 RFLAGS: 00010246 ... #7 [ffffc90001eafb60] visual_init at ffffffff8154c36e #8 [ffffc90001eafb80] vc_allocate at ffffffff8154f53c #9 [ffffc90001eafbc8] con_install at ffffffff8154f624 ... Signed-off-by: Grzegorz Halat Reviewed-by: Oleksandr Natalenko Acked-by: Bartlomiej Zolnierkiewicz Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/vt.c | 11 +++++++++-- drivers/video/fbdev/core/fbcon.c | 2 +- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index fdd12f8c3deb..5c0ca1c24b6f 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -1056,6 +1056,13 @@ static void visual_init(struct vc_data *vc, int num, int init) vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row; } + +static void visual_deinit(struct vc_data *vc) +{ + vc->vc_sw->con_deinit(vc); + module_put(vc->vc_sw->owner); +} + int vc_allocate(unsigned int currcons) /* return 0 on success */ { struct vt_notifier_param param; @@ -1103,6 +1110,7 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */ return 0; err_free: + visual_deinit(vc); kfree(vc); vc_cons[currcons].d = NULL; return -ENOMEM; @@ -1331,9 +1339,8 @@ struct vc_data *vc_deallocate(unsigned int currcons) param.vc = vc = vc_cons[currcons].d; atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, ¶m); vcs_remove_sysfs(currcons); - vc->vc_sw->con_deinit(vc); + visual_deinit(vc); put_pid(vc->vt_pid); - module_put(vc->vc_sw->owner); vc_uniscr_set(vc, NULL); kfree(vc->vc_screenbuf); vc_cons[currcons].d = NULL; diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index 786f9aab55df..a9c69ae30878 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -1248,7 +1248,7 @@ static void fbcon_deinit(struct vc_data *vc) if (free_font) vc->vc_font.data = NULL; - if (vc->vc_hi_font_mask) + if (vc->vc_hi_font_mask && vc->vc_screenbuf) set_vc_hi_font(vc, false); if (!con_is_bound(&fb_con))