linux-stable.git/drivers/tty/serial, branch v6.2.4

tty: serial: imx: disable Ageing Timer interrupt request irq

2023-03-10T08:28:55+00:00

[ Upstream commit ef25e16ea9674b713a68c3bda821556ce9901254 ]

There maybe pending USR interrupt before requesting irq, however
uart_add_one_port has not executed, so there will be kernel panic:
[    0.795668] Unable to handle kernel NULL pointer dereference at virtual addre
ss 0000000000000080
[    0.802701] Mem abort info:
[    0.805367]   ESR = 0x0000000096000004
[    0.808950]   EC = 0x25: DABT (current EL), IL = 32 bits
[    0.814033]   SET = 0, FnV = 0
[    0.816950]   EA = 0, S1PTW = 0
[    0.819950]   FSC = 0x04: level 0 translation fault
[    0.824617] Data abort info:
[    0.827367]   ISV = 0, ISS = 0x00000004
[    0.831033]   CM = 0, WnR = 0
[    0.833866] [0000000000000080] user address but active_mm is swapper
[    0.839951] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[    0.845953] Modules linked in:
[    0.848869] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.1+g56321e101aca #1
[    0.855617] Hardware name: Freescale i.MX8MP EVK (DT)
[    0.860452] pstate: 000000c5 (nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    0.867117] pc : __imx_uart_rxint.constprop.0+0x11c/0x2c0
[    0.872283] lr : imx_uart_int+0xf8/0x1ec

The issue only happends in the inmate linux when Jailhouse hypervisor
enabled. The test procedure is:
while true; do
	jailhouse enable imx8mp.cell
	jailhouse cell linux xxxx
	sleep 10
	jailhouse cell destroy 1
	jailhouse disable
	sleep 5
done

And during the upper test, press keys to the 2nd linux console.
When `jailhouse cell destroy 1`, the 2nd linux has no chance to put
the uart to a quiese state, so USR1/2 may has pending interrupts. Then
when `jailhosue cell linux xx` to start 2nd linux again, the issue
trigger.

In order to disable irqs before requesting them, both UCR1 and UCR2 irqs
should be disabled, so here fix that, disable the Ageing Timer interrupt
in UCR2 as UCR1 does.

Fixes: 8a61f0c70ae6 ("serial: imx: Disable irqs before requesting them")
Suggested-by: Sherry Sun 
Reviewed-by: Sherry Sun 
Signed-off-by: Peng Fan 
Acked-by: Jason Liu 
Link: https://lore.kernel.org/r/20230206013016.29352-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: fsl_lpuart: fix RS485 RTS polariy inverse issue

2023-03-10T08:28:54+00:00

[ Upstream commit 3957b9501a5a8fa709ae4a47483714491471f6db ]

The previous 'commit 846651eca073 ("serial: fsl_lpuart: RS485 RTS
polariy is inverse")' only fixed the inverse issue on lpuart 8bit
platforms.

This is a follow-up patch to fix the RS485 polarity inverse
issue on lpuart 32bit platforms.

Fixes: 03895cf41d18 ("tty: serial: fsl_lpuart: Add support for RS-485")
Reported-by: Sherry Sun 
Signed-off-by: Shenwei Wang 
Link: https://lore.kernel.org/r/20230207162420.3647904-1-shenwei.wang@nxp.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

tty: serial: fsl_lpuart: Fix the wrong RXWATER setting for rx dma case

2023-03-10T08:28:53+00:00

[ Upstream commit 9ad9df8447547febe9dd09b040f4528a09e495f0 ]

The RXWATER value must be greater than 0 according to the LPUART
reference manual. And when the number of datawords in the receive
FIFO is greater than RXWATER, an interrupt or a DMA request is
generated, so no need to set the different value for lpuart interrupt
case and dma case. Here delete the wrong RXWATER setting for dma case
directly.

Fixes: 42b68768e51b ("serial: fsl_lpuart: DMA support for 32-bit variant")
Signed-off-by: Sherry Sun 
Link: https://lore.kernel.org/r/20230130064449.9564-4-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: tegra: Add missing clk_disable_unprepare() in tegra_uart_hw_init()

2023-03-10T08:28:50+00:00

[ Upstream commit 38f28cfe9d08e3a47ef008798b275fef8118fc20 ]

Add the missing clk_disable_unprepare() before return from
tegra_uart_hw_init() in the error handling path.
When request_irq() fails in tegra_uart_startup(), 'tup->uart_clk'
has been enabled, fix it by adding clk_disable_unprepare().

Fixes: cc9ca4d95846 ("serial: tegra: Only print FIFO error message when an error occurs")
Fixes: d781ec21bae6 ("serial: tegra: report clk rate errors")
Signed-off-by: Yi Yang 
Link: https://lore.kernel.org/r/20221126020852.113378-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

tty: serial: fsl_lpuart: clear LPUART Status Register in lpuart32_shutdown()

2023-03-10T08:28:50+00:00

[ Upstream commit 4029dfc034febb54f6dd8ea83568accc943bc088 ]

The LPUART Status Register needs to be cleared when closing the uart
port to get a clean environment when reopening the uart.

Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Signed-off-by: Sherry Sun 
Link: https://lore.kernel.org/r/20221125101953.18753-4-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

tty: serial: fsl_lpuart: disable Rx/Tx DMA in lpuart32_shutdown()

2023-03-10T08:28:50+00:00

[ Upstream commit 1d4bd0e4ae4ba95892bef919a8d4d3f08f122d7e ]

UARTBAUD_RDMAE and UARTBAUD_TDMAE are enabled in lpuart32_startup(), but
lpuart32_shutdown() not disable them, only free the dma ring buffer and
release the dma channels, so here disable the Rx/Tx DMA first in
lpuart32_shutdown().

Fixes: 42b68768e51b ("serial: fsl_lpuart: DMA support for 32-bit variant")
Signed-off-by: Sherry Sun 
Link: https://lore.kernel.org/r/20221125101953.18753-3-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: 8250_dma: Fix DMA Rx rearm race

2023-01-31T10:15:16+00:00

As DMA Rx can be completed from two places, it is possible that DMA Rx
completes before DMA completion callback had a chance to complete it.
Once the previous DMA Rx has been completed, a new one can be started
on the next UART interrupt. The following race is possible
(uart_unlock_and_check_sysrq_irqrestore() replaced with
spin_unlock_irqrestore() for simplicity/clarity):

CPU0					CPU1
					dma_rx_complete()
serial8250_handle_irq()
  spin_lock_irqsave(&port->lock)
  handle_rx_dma()
    serial8250_rx_dma_flush()
      __dma_rx_complete()
        dma->rx_running = 0
        // Complete DMA Rx
  spin_unlock_irqrestore(&port->lock)

serial8250_handle_irq()
  spin_lock_irqsave(&port->lock)
  handle_rx_dma()
    serial8250_rx_dma()
      dma->rx_running = 1
      // Setup a new DMA Rx
  spin_unlock_irqrestore(&port->lock)

					  spin_lock_irqsave(&port->lock)
					  // sees dma->rx_running = 1
					  __dma_rx_complete()
					    dma->rx_running = 0
					    // Incorrectly complete
					    // running DMA Rx

This race seems somewhat theoretical to occur for real but handle it
correctly regardless. Check what is the DMA status before complething
anything in __dma_rx_complete().

Reported-by: Gilles BULOZ 
Tested-by: Gilles BULOZ 
Fixes: 9ee4b83e51f7 ("serial: 8250: Add support for dmaengine")
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20230130114841.25749-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

serial: 8250_dma: Fix DMA Rx completion race

2023-01-31T10:15:16+00:00

__dma_rx_complete() is called from two places:
  - Through the DMA completion callback dma_rx_complete()
  - From serial8250_rx_dma_flush() after IIR_RLSI or IIR_RX_TIMEOUT
The former does not hold port's lock during __dma_rx_complete() which
allows these two to race and potentially insert the same data twice.

Extend port's lock coverage in dma_rx_complete() to prevent the race
and check if the DMA Rx is still pending completion before calling
into __dma_rx_complete().

Reported-by: Gilles BULOZ 
Tested-by: Gilles BULOZ 
Fixes: 9ee4b83e51f7 ("serial: 8250: Add support for dmaengine")
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20230130114841.25749-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler

2023-01-31T10:15:01+00:00

Requesting an interrupt with IRQF_ONESHOT will run the primary handler
in the hard-IRQ context even in the force-threaded mode. The
force-threaded mode is used by PREEMPT_RT in order to avoid acquiring
sleeping locks (spinlock_t) in hard-IRQ context. This combination
makes it impossible and leads to "sleeping while atomic" warnings.

Use one interrupt handler for both handlers (primary and secondary)
and drop the IRQF_ONESHOT flag which is not needed.

Fixes: e359b4411c283 ("serial: stm32: fix threaded interrupt handling")
Reviewed-by: Sebastian Andrzej Siewior 
Tested-by: Valentin Caron  # V3
Signed-off-by: Marek Vasut 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230120160332.57930-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman

Merge tag 'tty-6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2023-01-21T19:12:42+00:00

Pull tty/serial driver fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 6.2-rc5 that
  resolve a number of tiny reported issues and some new device ids. They
  include:

   - new device id for the exar serial driver

   - speakup tty driver bugfix

   - atmel serial driver baudrate fixup

   - stm32 serial driver bugfix and then revert as the bugfix broke the
     build. That will come back in a later pull request once it is all
     worked out properly.

   - amba-pl011 serial driver rs486 mode bugfix

   - qcom_geni serial driver bugfix

  Most of these have been in linux-next with no reported problems (well,
  other than the build breakage which generated the revert), the new
  device id passed 0-day testing"

* tag 'tty-6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: exar: Add support for Sealevel 7xxxC serial cards
  Revert "serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler"
  tty: serial: qcom_geni: avoid duplicate struct member init
  serial: atmel: fix incorrect baudrate setup
  tty: fix possible null-ptr-defer in spk_ttyio_release
  serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler
  serial: amba-pl011: fix high priority character transmission in rs486 mode
  serial: pch_uart: Pass correct sg to dma_unmap_sg()
  tty: serial: qcom-geni-serial: fix slab-out-of-bounds on RX FIFO buffer