linux/drivers/tty, branch v5.0

Merge tag 'tty-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2019-02-08T18:49:55Z

Pull tty/serial fixes from Greg KH: "Here are some small tty and serial fixes for 5.0-rc6. Nothing huge, just a few small fixes for reported issues. The speakup fix is in here as it is a tty operation issue. All of these have been in linux-next for a while with no reported problems" * tag 'tty-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: serial: fix race between flush_to_ldisc and tty_open staging: speakup: fix tty-operation NULL derefs serial: sh-sci: Do not free irqs that have already been freed serial: 8250_pci: Make PCI class test non fatal tty: serial: 8250_mtk: Fix potential NULL pointer dereference

Merge tag 'riscv-for-linus-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

2019-02-02T18:26:14Z

Pull RISC-V fixes from Palmer Dabbelt: "This contains a handful of mostly-independent patches: - make our port respect TIF_NEED_RESCHED, which fixes CONFIG_PREEMPT=y kernels - fix double-put of OF nodes - fix a misspelling of target in our Kconfig - generic PCIe is enabled in our defconfig - fix our SBI early console to properly handle line endings - fix max_low_pfn being counted in PFNs - a change to TASK_UNMAPPED_BASE to match what other arches do This has passed my standard 'boot Fedora' flow" * tag 'riscv-for-linus-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: riscv: Adjust mmap base address at a third of task size riscv: fixup max_low_pfn with PFN_DOWN. tty/serial: use uart_console_write in the RISC-V SBL early console RISC-V: defconfig: Add CRYPTO_DEV_VIRTIO=y RISC-V: defconfig: Enable Generic PCIE by default RISC-V: defconfig: Move CONFIG_PCI{,E_XILINX} RISC-V: Kconfig: fix spelling mistake "traget" -> "target" RISC-V: asm/page.h: fix spelling mistake "CONFIG_64BITS" -> "CONFIG_64BIT" RISC-V: fix bad use of of_node_put RISC-V: Add _TIF_NEED_RESCHED check for kernel thread when CONFIG_PREEMPT=y

serial: fix race between flush_to_ldisc and tty_open

2019-01-31T18:43:04Z

There still is a race window after the commit b027e2298bd588 ("tty: fix data race between tty_init_dev and flush of buf"), and we encountered this crash issue if receive_buf call comes before tty initialization completes in tty_open and tty->driver_data may be NULL. CPU0 CPU1 ---- ---- tty_open tty_init_dev tty_ldisc_unlock schedule flush_to_ldisc receive_buf tty_port_default_receive_buf tty_ldisc_receive_buf n_tty_receive_buf_common __receive_buf uart_flush_chars uart_start /*tty->driver_data is NULL*/ tty->ops->open /*init tty->driver_data*/ it can be fixed by extending ldisc semaphore lock in tty_init_dev to driver_data initialized completely after tty->ops->open(), but this will lead to get lock on one function and unlock in some other function, and hard to maintain, so fix this race only by checking tty->driver_data when receiving, and return if tty->driver_data is NULL, and n_tty_receive_buf_common maybe calls uart_unthrottle, so add the same check. Because the tty layer knows nothing about the driver associated with the device, the tty layer can not do anything here, it is up to the tty driver itself to check for this type of race. Fix up the serial driver to correctly check to see if it is finished binding with the device when being called, and if not, abort the tty calls. [Description and problem report and testing from Li RongQing, I rewrote the patch to be in the serial layer, not in the tty core - gregkh] Reported-by: Li RongQing Tested-by: Li RongQing Signed-off-by: Wang Li Signed-off-by: Zhang Yu Signed-off-by: Li RongQing Cc: stable Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Do not free irqs that have already been freed

2019-01-30T08:35:46Z

Since IRQs might be muxed on some parts, we need to pay attention when we are freeing them. Otherwise we get the ugly WARNING "Trying to free already-free IRQ 20". Fixes: 628c534ae735 ("serial: sh-sci: Improve support for separate TEI and DRI interrupts") Cc: stable Signed-off-by: Chris Brandt Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Make PCI class test non fatal

2019-01-30T08:35:46Z

As has been reported the National Instruments serial cards have broken PCI class. The commit 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list") made the PCI class check mandatory for the case when device is listed in a quirk list. Make PCI class test non fatal to allow broken card be enumerated. Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list") Cc: stable Reported-by: Guan Yung Tseng Tested-by: Guan Yung Tseng Tested-by: KHUENY.Gerhard Signed-off-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman

tty: serial: 8250_mtk: Fix potential NULL pointer dereference

2019-01-30T08:35:46Z

There is a potential NULL pointer dereference in case devm_kzalloc() fails and returns NULL. Fix this by adding a NULL check on data->dma This bug was detected with the help of Coccinelle. Fixes: 85b5c1dd0456 ("serial: 8250-mtk: add uart DMA support") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Greg Kroah-Hartman

tty/serial: use uart_console_write in the RISC-V SBL early console

2019-01-23T23:41:50Z

This enables proper NLCR processing. Suggested-by: Anup Patel Signed-off-by: Andreas Schwab Reviewed-by: Anup Patel Reviewed-by: Christoph Hellwig Signed-off-by: Palmer Dabbelt

serial: fsl_lpuart: fix maximum acceptable baud rate with over-sampling

2019-01-22T08:32:08Z

Using over-sampling ratio, lpuart can accept baud rate upto uartclk / 4. Signed-off-by: Tomonori Sakita Signed-off-by: Atsushi Nemoto Signed-off-by: Greg Kroah-Hartman

tty: serial: qcom_geni_serial: Allow mctrl when flow control is disabled

2019-01-22T08:32:07Z

The geni set/get_mctrl() functions currently do nothing unless hardware flow control is enabled. Remove this arbitrary limitation. Suggested-by: Johan Hovold Fixes: 8a8a66a1a18a ("tty: serial: qcom_geni_serial: Add support for flow control") Signed-off-by: Matthias Kaehlcke Reviewed-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman

tty: Handle problem if line discipline does not have receive_buf

2019-01-21T16:41:02Z

Some tty line disciplines do not have a receive buf callback, so properly check for that before calling it. If they do not have this callback, just eat the character quietly, as we can't fail this call. Reported-by: Jann Horn Cc: stable Signed-off-by: Greg Kroah-Hartman