Pull tty / serial updates from Greg KH:
 "Here is the big set of tty and serial driver changes for 6.8-rc1.

  As usual, Jiri has a bunch of refactoring and cleanups for the tty
  core and drivers in here, along with the usual set of rs485 updates
  (someday this might work properly...)

  Along with those, in here are changes for:

   - sc16is7xx serial driver updates

   - platform driver removal api updates

   - amba-pl011 driver updates

   - tty driver binding updates

   - other small tty/serial driver updates and changes

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (197 commits)
  serial: sc16is7xx: refactor EFR lock
  serial: sc16is7xx: reorder code to remove prototype declarations
  serial: sc16is7xx: refactor FIFO access functions to increase commonality
  serial: sc16is7xx: drop unneeded MODULE_ALIAS
  serial: sc16is7xx: replace hardcoded divisor value with BIT() macro
  serial: sc16is7xx: add explicit return for some switch default cases
  serial: sc16is7xx: add macro for max number of UART ports
  serial: sc16is7xx: add driver name to struct uart_driver
  serial: sc16is7xx: use i2c_get_match_data()
  serial: sc16is7xx: use spi_get_device_match_data()
  serial: sc16is7xx: use DECLARE_BITMAP for sc16is7xx_lines bitfield
  serial: sc16is7xx: improve do/while loop in sc16is7xx_irq()
  serial: sc16is7xx: remove obsolete loop in sc16is7xx_port_irq()
  serial: sc16is7xx: set safe default SPI clock frequency
  serial: sc16is7xx: add check for unsupported SPI modes during probe
  serial: sc16is7xx: fix invalid sc16is7xx_lines bitfield in case of probe error
  serial: 8250_exar: Set missing rs485_supported flag
  serial: omap: do not override settings for RS485 support
  serial: core, imx: do not set RS485 enabled if it is not supported
  serial: core: make sure RS485 cannot be enabled when it is not supported
  ...

Pull UML updates from Richard Weinberger:

 - Clang coverage support

 - Many cleanups from Benjamin Berg

 - Various minor fixes

* tag 'uml-for-linus-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
  um: Mark 32bit syscall helpers as clobbering memory
  um: Remove unused register save/restore functions
  um: Rely on PTRACE_SETREGSET to set FS/GS base registers
  Documentation: kunit: Add clang UML coverage example
  arch: um: Add Clang coverage support
  um: time-travel: fix time corruption
  um: net: Fix return type of uml_net_start_xmit()
  um: Always inline stub functions
  um: Do not use printk in userspace trampoline
  um: Reap winch thread if it fails
  um: Do not use printk in SIGWINCH helper thread
  um: Don't use vfprintf() for os_info()
  um: Make errors to stop ptraced child fatal during startup
  um: Drop NULL check from start_userspace
  um: Drop support for hosts without SYSEMU_SINGLESTEP support
  um: document arch_futex_atomic_op_inuser
  um: mmu: remove stub_pages
  um: Fix naming clash between UML and scheduler
  um: virt-pci: fix platform map offset

With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed. A
warning in clang aims to catch these at compile time, which reveals:

  arch/um/drivers/net_kern.c:353:21: warning: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Wincompatible-function-pointer-types-strict]
    353 |         .ndo_start_xmit         = uml_net_start_xmit,
        |                                   ^~~~~~~~~~~~~~~~~~
  1 warning generated.

->ndo_start_xmit() in 'struct net_device_ops' expects a return type of
'netdev_tx_t', not 'int'. Adjust the return type of uml_net_start_xmit()
to match the prototype's to resolve the warning. While UML does not
currently implement support for kCFI, it could in the future, which
means this warning becomes a fatal CFI failure at run time.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310031340.v1vPh207-lkp@intel.com/
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

When the winch thread runs into an error condition, it would exit(1) and
never be reaped until shutdown time. Change this to write a command byte
which causes the driver to kill it, therefore reaping the child.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>

The thread is running outside of the UML kernel scope and is a helper.
As such, printk cannot work and os_info must be used instead.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>

The offset is currently always zero so the backend can't distinguish
between accesses to different ioremapped areas.

Fixes: 522c532c4fe7 ("virt-pci: add platform bus support")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

The discard granularity now defaults to a single sector, so don't set
that value explicitly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/r/20231228075545.362768-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Switch character types to u8 and sizes to size_t. To conform to
characters/sizes in the rest of the tty layer.

Note we use __u8 in the userspace files.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-um@lists.infradead.org
Link: https://lore.kernel.org/r/20231206073712.17776-27-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull UML updates from Richard Weinberger:

 - Drop 32-bit checksum implementation and re-use it from arch/x86

 - String function cleanup

 - Fixes for -Wmissing-variable-declarations and -Wmissing-prototypes
   builds

* tag 'uml-for-linus-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
  um: virt-pci: fix missing declaration warning
  um: Refactor deprecated strncpy to memcpy
  um: fix 3 instances of -Wmissing-prototypes
  um: port_kern: fix -Wmissing-variable-declarations
  uml: audio: fix -Wmissing-variable-declarations
  um: vector: refactor deprecated strncpy
  um: use obj-y to descend into arch/um/*/
  um: Hard-code the result of 'uname -s'
  um: Use the x86 checksum implementation on 32-bit
  asm-generic: current: Don't include thread-info.h if building asm
  um: Remove unsued extern declaration ldt_host_info()
  um: Fix hostaudio build errors
  um: Remove strlcpy usage

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver changes for 6.6-rc1.

  Lots of cleanups in here this cycle, and some driver updates. Short
  summary is:

   - Jiri's continued work to make the tty code and apis be a bit more
     sane with regards to modern kernel coding style and types

   - cpm_uart driver updates

   - n_gsm updates and fixes

   - meson driver updates

   - sc16is7xx driver updates

   - 8250 driver updates for different hardware types

   - qcom-geni driver fixes

   - tegra serial driver change

   - stm32 driver updates

   - synclink_gt driver cleanups

   - tty structure size reduction

  All of these have been in linux-next this week with no reported
  issues. The last bit of cleanups from Jiri and the tty structure size
  reduction came in last week, a bit late but as they were just style
  changes and size reductions, I figured they should get into this merge
  cycle so that others can work on top of them with no merge conflicts"

* tag 'tty-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits)
  tty: shrink the size of struct tty_struct by 40 bytes
  tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw()
  tty: n_tty: extract ECHO_OP processing to a separate function
  tty: n_tty: unify counts to size_t
  tty: n_tty: use u8 for chars and flags
  tty: n_tty: simplify chars_in_buffer()
  tty: n_tty: remove unsigned char casts from character constants
  tty: n_tty: move newline handling to a separate function
  tty: n_tty: move canon handling to a separate function
  tty: n_tty: use MASK() for masking out size bits
  tty: n_tty: make n_tty_data::num_overrun unsigned
  tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun()
  tty: n_tty: use 'num' for writes' counts
  tty: n_tty: use output character directly
  tty: n_tty: make flow of n_tty_receive_buf_common() a bool
  Revert "tty: serial: meson: Add a earlycon for the T7 SoC"
  Documentation: devices.txt: Fix minors for ttyCPM*
  Documentation: devices.txt: Remove ttySIOC*
  Documentation: devices.txt: Remove ttyIOC*
  serial: 8250_bcm7271: improve bcm7271 8250 port
  ...