The vc_cons_allocated() checks in vt_ioctl() and vt_compat_ioctl() are
unnecessary because they can only be reached by calling ioctl() on an
open tty, which implies the corresponding virtual console is allocated.

And even if the virtual console *could* be freed concurrently, then
these checks would be broken since they aren't done under console_lock,
and the vc_data is dereferenced before them anyway.

So, remove these unneeded checks to avoid confusion.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224080326.295046-1-ebiggers@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The might_sleep() in do_con_write() is redundant because console_lock()
already contains might_sleep().  Remove it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224073450.292892-1-ebiggers@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Refactor uart_unlock_and_check_sysrq() to:

  - explicitly show that we release a port lock which makes
    static analyzers happy:

CHECK   drivers/tty/serial/serial_core.c
.../serial_core.c:3290:17: warning: context imbalance in 'uart_unlock_and_check_sysrq' - unexpected unlock

  - use flags instead of irqflags to avoid confusion with IRQ flags

  - provide one return point

  - be more compact
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://lore.kernel.org/r/20200310174337.74109-4-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use uart_console() helper in SysRq code instead of open coded variant.
This eliminates the conditional entirely for SERIAL_CORE_CONSOLE=n case.
While here, refactor the conditional to be more compact.
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200310174337.74109-3-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

It is useful to see on the serial console the magic sequence itself
to enable SysRq without rummaging source code.
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200310174337.74109-2-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Compiler is not happy about using ARRAY_SIZE() in comparison to smaller type:

  CC      drivers/tty/serial/serial_core.o
.../serial_core.c: In function ‘uart_try_toggle_sysrq’:
.../serial_core.c:3222:24: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 3222 |  if (++port->sysrq_seq < (ARRAY_SIZE(sysrq_toggle_seq) - 1)) {
      |                        ^

Looking at the code it appears that there is an additional weirdness,
i.e. use ARRAY_SIZE() against simple string literal. Yes, the idea probably
was to allow '\0' in the sequence, but it's impractical: kernel configuration
won't accept it to begin with followed by a comment about '\0' before
comparison in question.

Drop all these by switching to strlen() and convert code accordingly.

Note, GCC seems clever enough to calculate string length at compile time.

Fixes: 68af4317 ("serial/sysrq: Add MAGIC_SYSRQ_SERIAL_SEQUENCE")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200310174337.74109-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

To fix the RX cancel command failure, rx_fifo buffer needs to be
flushed in stop_rx() by calling handle_rx().In handle_rx() the data
in rx_fifo buffer is read and then dropped, not sent to upper layers.

If set_termios is called before startup, by this time memory is not
allocated to port->rx_fifo buffer, which leads to a NULL pointer
dereference.

To avoid this NULL pointer dereference allocate memory to port->rx_fifo
in probe itself.
Signed-off-by: satya priya <skakit@codeaurora.org>
Reported-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1583477228-32231-2-git-send-email-skakit@codeaurora.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver for the Intel MID never seems to have been properly
integrated upstream: the platform data in <linux/spi/ifx_modem.h>
is not used anywhere in the kernel and haven't been since it was
merged into the kernel in 2010.

There might be out-of-tree users, so I don't want to delete the
driver, but I will refactor it to use GPIO descriptors, which
means that out-of-tree users will need to adapt.

There are several examples in the kernel of how to provide the
resources necessary for using GPIO descriptors to pass in the
GPIO lines, for the MID platform in particular, it will suffice
to inspect the code in files like:
arch/x86/platform/intel-mid/device_libs/platform_bt.c

This refactoring transfers all GPIOs in the driver, including
a hard-coded "PMU reset" in the driver to use GPIO descriptors
instead.

The following named GPIO descriptors need to be supplied:
- reset
- power
- mrdy
- srdy
- rst_out
- pmu_reset

Cc: Russ Gorby <russ.gorby@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200311083131.693908-2-linus.walleij@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The &spi->dev is used so many times that the code gets
visibly better by introducing a simple dev helper variable.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200311083131.693908-1-linus.walleij@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The LS1028A has six LPUART controllers. Add the nodes.

This was tested on a custom board.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200307091302.14881-2-michael@walle.ccSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add the LS1028A SoC compatibility string to the lpuart devicetree
bindings documentation.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200307091302.14881-1-michael@walle.ccSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a early_console_setup() for the LS1028A SoC with 32bit, little
endian access. If the bootloader does a fixup of the clock-frequency
node the baudrate divisor register will automatically be set.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-5-michael@walle.ccSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The LS1028A uses little endian register access and has a different FIFO
size encoding.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-4-michael@walle.ccSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the correct device to request the DMA mapping. Otherwise the IOMMU
doesn't get the mapping and it will generate a page fault.

The error messages look like:
[   19.012140] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xbbfff800, fsynr=0x3e0021, cbfrsynra=0x828, cb=9
[   19.023593] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xbbfff800, fsynr=0x3e0021, cbfrsynra=0x828, cb=9

This was tested on a custom board with a LS1028A SoC.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-3-michael@walle.ccSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The DMA channel might not be available at probe time. This is esp. the
case if the DMA controller has an IOMMU mapping.

There is also another caveat. If there is no DMA controller at all,
dma_request_chan() will also return -EPROBE_DEFER. Thus we cannot test
for -EPROBE_DEFER in probe(). Otherwise the lpuart driver will fail to
probe if, for example, the DMA driver is not enabled in the kernel
configuration.

To workaround this, we request the DMA channel in _startup(). Other
serial drivers do it the same way.
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-2-michael@walle.ccSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

To make it more obvious what almost everyone wants to set here.

Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vasiliy Khoruzhick <vasilykh@arista.com>
Cc: linux-serial@vger.kernel.org
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200306153156.579921-1-dima@arista.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use uart_console() helper in instead of open coded variant.

Note, SERIAL_CORE_CONSOLE is selected by SERIAL_ATMEL_CONSOLE,
thus no functional changes expected.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Link: https://lore.kernel.org/r/20200310133057.86840-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use uart_console() helper in instead of open coded variant.

Note, SERIAL_CORE_CONSOLE is selected by SERIAL_PIC32_CONSOLE,
thus no functional changes expected.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200311090027.64441-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

SiFive's UART has a software controller clock divider that produces the
final baud rate clock.  Whenever the clock that drives the UART is
changed this divider must be updated accordingly, and given that these
two events are controlled by software they cannot be done atomically.
During the period between updating the UART's driving clock and internal
divider the UART will transmit a different baud rate than what the user
has configured, which will probably result in a corrupted transmission
stream.

The SiFive UART has a FIFO, but due to an issue with the programming
interface there is no way to directly determine when the UART has
finished transmitting.  We're essentially restricted to dead reckoning
in order to figure that out: we can use the FIFO's TX busy register to
figure out when the last frame has begun transmission and just delay for
a long enough that the last frame is guaranteed to get out.

As far as the actual implementation goes: I've modified the existing
existing clock notifier function to drain both the FIFO and the shift
register in on PRE_RATE_CHANGE.  As far as I know there is no hardware
flow control in this UART, so there's no good way to ask the other end
to stop transmission while we can't receive (inserting software flow
control messages seems like a bad idea here).
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Tested-by: Yash Shah <yash.shah@sifive.com>
Link: https://lore.kernel.org/r/20200307042637.83728-1-palmer@dabbelt.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We need the vt fixes in here and it resolves a merge issue with
drivers/tty/vt/selection.c
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull ARM SoC fixes from Olof Johansson:
 "We've been accruing these for a couple of weeks, so the batch is a bit
  bigger than usual.

  Largest delta is due to a led-bl driver that is added -- there was a
  miscommunication before the merge window and the driver didn't make it
  in. Due to this, the platforms needing it regressed. At this point, it
  seemed easier to add the new driver than unwind the changes.

  Besides that, there are a handful of various fixes:

   - AMD tee memory leak fix

   - A handful of fixlets for i.MX SCU communication

   - A few maintainers woke up and realized DEBUG_FS had been missing
     for a while, so a few updates of that.

  ... and the usual collection of smaller fixes to various platforms"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (37 commits)
  ARM: socfpga_defconfig: Add back DEBUG_FS
  arm64: dts: socfpga: agilex: Fix gmac compatible
  ARM: bcm2835_defconfig: Explicitly restore CONFIG_DEBUG_FS
  arm64: dts: meson: fix gxm-khadas-vim2 wifi
  arm64: dts: meson-sm1-sei610: add missing interrupt-names
  ARM: meson: Drop unneeded select of COMMON_CLK
  ARM: dts: bcm2711: Add pcie0 alias
  ARM: dts: bcm283x: Add missing properties to the PWR LED
  tee: amdtee: fix memory leak in amdtee_open_session()
  ARM: OMAP2+: Fix compile if CONFIG_HAVE_ARM_SMCCC is not set
  arm: dts: dra76x: Fix mmc3 max-frequency
  ARM: dts: dra7: Add "dma-ranges" property to PCIe RC DT nodes
  bus: ti-sysc: Fix 1-wire reset quirk
  ARM: dts: r8a7779: Remove deprecated "renesas, rcar-sata" compatible value
  soc: imx-scu: Align imx sc msg structs to 4
  firmware: imx: Align imx_sc_msg_req_cpu_start to 4
  firmware: imx: scu-pd: Align imx sc msg structs to 4
  firmware: imx: misc: Align imx sc msg structs to 4
  firmware: imx: scu: Ensure sequential TX
  ARM: dts: imx7-colibri: Fix frequency for sd/mmc
  ...

Pull EDAC fix from Borislav Petkov:
 "Error reporting fix for synopsys_edac: do not overwrite partial
  decoded error message (Sherry Sun)"

* tag 'edac_urgent-2020-03-08' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
  EDAC/synopsys: Do not print an error with back-to-back snprintf() calls

Pull char/misc fixes from Greg KH:
 "Here are four small char/misc driver fixes for reported issues for
  5.6-rc5.

  These fixes are:

   - binder fix for a potential use-after-free problem found (took two
     tries to get it right)

   - interconnect core fix

   - altera-stapl driver fix

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

* tag 'char-misc-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  binder: prevent UAF for binderfs devices II
  interconnect: Handle memory allocation errors
  altera-stapl: altera_get_note: prevent write beyond end of 'key'
  binder: prevent UAF for binderfs devices

Pull driver core and debugfs fixes from Greg KH:
 "Here are four small driver core / debugfs patches for 5.6-rc3:

   - debugfs api cleanup now that all debugfs_create_regset32() callers
     have been fixed up. This was waiting until after the -rc1 merge as
     these fixes came in through different trees

   - driver core sync state fixes based on reports of minor issues found
     in the feature

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

* tag 'driver-core-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  driver core: Skip unnecessary work when device doesn't have sync_state()
  driver core: Add dev_has_sync_state()
  driver core: Call sync_state() even if supplier has no consumers
  debugfs: remove return value of debugfs_create_regset32()

Pull tty/serial fixes from Greg KH:
 "Here are some small tty/serial fixes for 5.6-rc5

  Just some small serial driver fixes, and a vt core fixup, full details
  are:

   - vt fixes for issues found by syzbot

   - serdev fix for Apple boxes

   - fsl_lpuart serial driver fixes

   - MAINTAINER update for incorrect serial files

   - new device ids for 8250_exar driver

   - mvebu-uart fix

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

* tag 'tty-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: serial: fsl_lpuart: free IDs allocated by IDA
  Revert "tty: serial: fsl_lpuart: drop EARLYCON_DECLARE"
  serdev: Fix detection of UART devices on Apple machines.
  MAINTAINERS: Add missed files related to Synopsys DesignWare UART
  serial: 8250_exar: add support for ACCES cards
  tty:serial:mvebu-uart:fix a wrong return
  vt: selection, push sel_lock up
  vt: selection, push console lock down

Pull USB/PHY fixes from Greg KH:
 "Here are some small USB and PHY driver fixes for reported issues for
  5.6-rc5.

  Included in here are:

   - phy driver fixes

   - new USB quirks

   - USB cdns3 gadget driver fixes

   - USB hub core fixes

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

* tag 'usb-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: dwc3: gadget: Update chain bit correctly when using sg list
  usb: core: port: do error out if usb_autopm_get_interface() fails
  usb: core: hub: do error out if usb_autopm_get_interface() fails
  usb: core: hub: fix unhandled return by employing a void function
  usb: storage: Add quirk for Samsung Fit flash
  usb: quirks: add NO_LPM quirk for Logitech Screen Share
  usb: usb251xb: fix regulator probe and error handling
  phy: allwinner: Fix GENMASK misuse
  usb: cdns3: gadget: toggle cycle bit before reset endpoint
  usb: cdns3: gadget: link trb should point to next request
  phy: mapphone-mdm6600: Fix timeouts by adding wake-up handling
  phy: brcm-sata: Correct MDIO operations for 40nm platforms
  phy: ti: gmii-sel: do not fail in case of gmii
  phy: ti: gmii-sel: fix set of copy-paste errors
  phy: core: Fix phy_get() to not return error on link creation failure
  phy: mapphone-mdm6600: Fix write timeouts with shorter GPIO toggle interval

Pull rdma fixes from Jason Gunthorpe:
 "Nothing particularly exciting, some small ODP regressions from the mmu
  notifier rework, another bunch of syzkaller fixes, and a bug fix for a
  botched syzkaller fix in the first rc pull request.

   - Fix busted syzkaller fix in 'get_new_pps' - this turned out to
     crash on certain HW configurations

   - Bug fixes for various missed things in error unwinds

   - Add a missing rcu_read_lock annotation in hfi/qib

   - Fix two ODP related regressions from the recent mmu notifier
     changes

   - Several more syzkaller bugs in siw, RDMA netlink, verbs and iwcm

   - Revert an old patch in CMA as it is now shown to not be allocating
     port numbers properly"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/iwcm: Fix iwcm work deallocation
  RDMA/siw: Fix failure handling during device creation
  RDMA/nldev: Fix crash when set a QP to a new counter but QPN is missing
  RDMA/odp: Ensure the mm is still alive before creating an implicit child
  RDMA/core: Fix protection fault in ib_mr_pool_destroy
  IB/mlx5: Fix implicit ODP race
  IB/hfi1, qib: Ensure RCU is locked when accessing list
  RDMA/core: Fix pkey and port assignment in get_new_pps
  RMDA/cm: Fix missing ib_cm_destroy_id() in ib_cm_insert_listen()
  RDMA/rw: Fix error flow during RDMA context initialization
  RDMA/core: Fix use of logical OR in get_new_pps
  Revert "RDMA/cma: Simplify rdma_resolve_addr() error flow"

Pull io_uring fixes from Jens Axboe:
 "Here are a few io_uring fixes that should go into this release. This
  contains:

   - Removal of (now) unused io_wq_flush() and associated flag (Pavel)

   - Fix cancelation lockup with linked timeouts (Pavel)

   - Fix for potential use-after-free when freeing percpu ref for fixed
     file sets

   - io-wq cancelation fixups (Pavel)"

* tag 'io_uring-5.6-2020-03-07' of git://git.kernel.dk/linux-block:
  io_uring: fix lockup with timeouts
  io_uring: free fixed_file_data after RCU grace period
  io-wq: remove io_wq_flush and IO_WQ_WORK_INTERNAL
  io-wq: fix IO_WQ_WORK_NO_CANCEL cancellation

Pull block fixes from Jens Axboe:
 "Here are a few fixes that should go into this release. This contains:

   - Revert of a bad bcache patch from this merge window

   - Removed unused function (Daniel)

   - Fixup for the blktrace fix from Jan from this release (Cengiz)

   - Fix of deeper level bfqq overwrite in BFQ (Carlo)"

* tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block:
  block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
  blktrace: fix dereference after null check
  Revert "bcache: ignore pending signals when creating gc and allocator thread"
  block: Remove used kblockd_schedule_work_on()

Pull media fixes from Mauro Carvalho Chehab:

 - a fix for the media controller links in both hantro driver and in
   v4l2-mem2mem core

 - some fixes for the pulse8-cec driver

 - vicodec: handle alpha channel for RGB32 formats, as it may be used

 - mc-entity.c: fix handling of pad flags

* tag 'media/v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: hantro: Fix broken media controller links
  media: mc-entity.c: use & to check pad flags, not ==
  media: v4l2-mem2mem.c: fix broken links
  media: vicodec: process all 4 components for RGB32 formats
  media: pulse8-cec: close serio in disconnect, not adap_free
  media: pulse8-cec: INIT_DELAYED_WORK was called too late

There is a recipe to deadlock the kernel: submit a timeout sqe with a
linked_timeout (e.g.  test_single_link_timeout_ception() from liburing),
and SIGKILL the process.

Then, io_kill_timeouts() takes @ctx->completion_lock, but the timeout
isn't flagged with REQ_F_COMP_LOCKED, and will try to double grab it
during io_put_free() to cancel the linked timeout. Probably, the same
can happen with another io_kill_timeout() call site, that is
io_commit_cqring().
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull s390 fixes from Vasily Gorbik:

 - Fix panic in gup_fast on large pud by providing an implementation of
   pud_write. This has been overlooked during migration to common gup
   code.

 - Fix unexpected write combining on PCI stores.

* tag 's390-5.6-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pci: Fix unexpected write combine on resource
  s390/mm: fix panic in gup_fast on large pud

Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 5.6:

   - One fix for a recent regression to our breakpoint/watchpoint code.

   - Another fix for our KUAP support, this time a missing annotation in
     a rarely used path in signal handling.

   - A fix for our handling of a CPU feature that effects the PMU, when
     booting guests in some configurations.

   - A minor fix to our linker script to explicitly include the .BTF
     section.

  Thanks to: Christophe Leroy, Desnes A. Nunes do Rosario, Leonardo
  Bras, Naveen N. Rao, Ravi Bangoria, Stefan Berger"

* tag 'powerpc-5.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/mm: Fix missing KUAP disable in flush_coherent_icache()
  powerpc: fix hardware PMU exception bug on PowerVM compatibility mode systems
  powerpc: Include .BTF section
  powerpc/watchpoint: Don't call dar_within_range() for Book3S

Pull xen fixes from Juergen Gross:
 "Four fixes and a small cleanup patch:

   - two fixes by Dongli Zhang fixing races in the xenbus driver

   - two fixes by me fixing issues introduced in 5.6

   - a small cleanup by Gustavo Silva replacing a zero-length array with
     a flexible-array"

* tag 'for-linus-5.6b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/blkfront: fix ring info addressing
  xen/xenbus: fix locking
  xenbus: req->err should be updated before req->state
  xenbus: req->body should be updated before req->state
  xen: Replace zero-length array with flexible-array member

Pull thread fixes from Christian Brauner:
 "Here are a few hopefully uncontroversial fixes:

   - Use RCU_INIT_POINTER() when initializing rcu protected members in
     task_struct to fix sparse warnings.

   - Add pidfd_fdinfo_test binary to .gitignore file"

* tag 'for-linus-2020-03-07' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux:
  selftests: pidfd: Add pidfd_fdinfo_test in .gitignore
  exit: Fix Sparse errors and warnings
  fork: Use RCU_INIT_POINTER() instead of rcu_access_pointer()

Pull sound fixes from Takashi Iwai:
 "The regular "bump-in-the-middle" updates, containing mostly ASoC-
  related fixes at this time. All changes are reasonably small.

  A few entries are for ASoC and ALSA core parts (DAPM, PCM, topology)
  for followups of the recent changes and potential buffer overflow by
  snprintf(), while the rest are (both new and old) device-specific
  fixes for Intel, meson, tas2562, rt1015, as well as the usual HD-audio
  quirks"

* tag 'sound-5.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (25 commits)
  ALSA: sgio2audio: Remove usage of dropped hw_params/hw_free functions
  ALSA: hda/realtek - Enable the headset of ASUS B9450FA with ALC294
  ALSA: hda/realtek - Fix silent output on Gigabyte X570 Aorus Master
  ALSA: hda/realtek - Add Headset Button supported for ThinkPad X1
  ALSA: hda/realtek - Add Headset Mic supported
  ASoC: wm8741: Fix typo in Kconfig prompt
  ASoC: stm32: sai: manage rebind issue
  ASoC: SOF: Fix snd_sof_ipc_stream_posn()
  ASoC: rt1015: modify pre-divider for sysclk
  ASoC: rt1015: add operation callback function for rt1015_dai[]
  ASoC: soc-component: tidyup snd_soc_pcm_component_sync_stop()
  ASoC: dapm: Correct DAPM handling of active widgets during shutdown
  ASoC: tas2562: Fix sample rate error message
  ASoC: Intel: Skylake: Fix available clock counter incrementation
  ASoC: soc-pcm/soc-compress: don't use snd_soc_dapm_stream_stop()
  ASoC: meson: g12a: add tohdmitx reset
  ASoC: pcm512x: Fix unbalanced regulator enable call in probe error path
  ASoC: soc-core: fix for_rtd_codec_dai_rollback() macro
  ASoC: topology: Fix memleak in soc_tplg_manifest_load()
  ASoC: topology: Fix memleak in soc_tplg_link_elems_load()
  ...

Mark mips_ejtag_fdc_encode() methods switch-case-4 as expecting to
fall through.

This patch fixes the following warning:

drivers/tty/mips_ejtag_fdc.c: In function ‘mips_ejtag_fdc_encode’:
drivers/tty/mips_ejtag_fdc.c:245:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   word.word &= 0x00ffffff;
   ~~~~~~~~~~^~~~~~~~~~~~~
drivers/tty/mips_ejtag_fdc.c:246:2: note: here
  case 3:
  ^~~~
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Link: https://lore.kernel.org/r/20200306124913.151A68030792@mail.baikalelectronics.ruSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.

Currently, sysrq can be either completely disabled for serial console
or always disabled (with CONFIG_MAGIC_SYSRQ_SERIAL), since
commit 732dbf3a ("serial: do not accept sysrq characters via serial port")

At Arista, we have such boards that can generate BREAK and random
garbage. While disabling sysrq for serial console would solve
the problem with spurious false sysrq triggers, it's also desirable
to have a way to enable sysrq back.

As a measure of balance between on and off options, add
MAGIC_SYSRQ_SERIAL_SEQUENCE which is a string sequence that can enable
sysrq if it follows BREAK on a serial line. The longer the string - the
less likely it may be in the garbage.

Having the way to enable sysrq was beneficial to debug lockups with
a manual investigation in field and on the other side preventing false
sysrq detections.
Based-on-patch-by: Vasiliy Khoruzhick <vasilykh@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200302175135.269397-3-dima@arista.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.

Currently, sysrq can be either completely disabled for serial console
or always disabled (with CONFIG_MAGIC_SYSRQ_SERIAL), since
commit 732dbf3a ("serial: do not accept sysrq characters via serial port")

At Arista, we have such boards that can generate BREAK and random
garbage. While disabling sysrq for serial console would solve
the problem with spurious false sysrq triggers, it's also desirable
to have a way to enable sysrq back.

Having the way to enable sysrq was beneficial to debug lockups with
a manual investigation in field and on the other side preventing false
sysrq detections.

As a preparation to add sysrq_toggle_support() call into uart,
remove a private copy of sysrq_enabled from sysctl - it should reflect
the actual status of sysrq.

Furthermore, the private copy isn't correct already in case
sysrq_always_enabled is true. So, remove __sysrq_enabled and use a
getter-helper sysrq_mask() to check sysrq_key_op enabled status.

Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200302175135.269397-2-dima@arista.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>