Factor out the duplicated code for in-kernel and external module
cleaning.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The in-kernel build and external module build have similar code
for descending into sub-directories.

Factor out the code into the common place.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

There is no need to set 0 to variables such as config-targets,
mixed-targets, etc.

Unset instead of setting 0 in order to use 'ifdef' to test them.

I also renamed:

  config-targets  ->  config-build
  mixed-targets   ->  mixed-build
  dot-config      ->  need-config

to clarify what we are doing.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

'make clean' descends into ./Kbuild, but does not clean anything
since everything is added to no-clean-files.

There is no need to descend to ./Kbuild in the first place.
We can drop the no-clean-files assignment.

With this, there is no more user of no-clean-files. I will keep it
for a while to see whether a new user will appear.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

timeconst.h is generated by $(call filechk,...), missing-syscalls and
old-atomics are invoked by $(call cmd,...)

None of them needs to be added to 'targets'.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

'make /' is just an alias for 'make ./'; this builds all objects of an
external module, but skips the modpost stage.

I am not a big fan of 'make /' since it looks as if it were touching
the root directory of the system. I like 'make ./' better.

I do not know how many people are using it, but let's show a hint if
it is used. Also, move it close to the external module rules since
this only makes sense for external modules.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

For the single target building %.symtypes from %.S, $(a_flags) is
expanded into the _KERNEL flags even if the object is a part of a
module.

$(real-obj-m:.o=.symtypes): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)

... would fix the issue, but it is not nice to duplicate similar code
for every suffix.

Implement modkern_aflags in the same way as modkern_cflags.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Make it even shorter.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

$(objtree)/Module.symvers is not required for descending into
sub-directories. It is needed for the modpost stage.

Move the Module.symvers check to the right place.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Currently, Kbuild treats an object as multi-used when any of
$(foo-objs), $(foo-y), $(foo-m) is set. It makes more sense to
check $(foo-) as well.

In the context of foo-$(CONFIG_FOO_FEATURE1), CONFIG_FOO_FEATURE1
could be unset.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

This builds module objects, so [M] makes sense.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Update the build scripts and the version magic to reflect when
CONFIG_PREEMPT_RT is enabled in the same way as CONFIG_PREEMPT is treated.

The resulting version strings:

  Linux m 5.3.0-rc1+ #100 SMP Fri Jul 26 ...
  Linux m 5.3.0-rc1+ #101 SMP PREEMPT Fri Jul 26 ...
  Linux m 5.3.0-rc1+ #102 SMP PREEMPT_RT Fri Jul 26 ...

The module vermagic:

  5.3.0-rc1+ SMP mod_unload modversions
  5.3.0-rc1+ SMP preempt mod_unload modversions
  5.3.0-rc1+ SMP preempt_rt mod_unload modversions
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Flex and bison are used for kconfig, dtc, genksyms, all of which are
host programs. I never imagine the kernel embeds a parser or a lexer.

Move the flex and bison rules to scripts/Makefile.host. This file is
included only when hostprogs-y etc. is present in the Makefile in the
directory. So, parsing these rules are skipped in most of directories.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

We generally expect bison to create not only a C file, but also a
header, which will be included from the lexer.

Currently, Kbuild generates them in separate rules. So, for instance,
when building Kconfig, you will notice bison is invoked twice:

  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/confdata.o
  HOSTCC  scripts/kconfig/expr.o
  LEX     scripts/kconfig/lexer.lex.c
  YACC    scripts/kconfig/parser.tab.h
  HOSTCC  scripts/kconfig/lexer.lex.o
  YACC    scripts/kconfig/parser.tab.c
  HOSTCC  scripts/kconfig/parser.tab.o
  HOSTCC  scripts/kconfig/preprocess.o
  HOSTCC  scripts/kconfig/symbol.o
  HOSTLD  scripts/kconfig/conf

Make handles such cases nicely in pattern rules [1]. Merge the two
rules so that one invokcation of bison can generate both of them.

  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/confdata.o
  HOSTCC  scripts/kconfig/expr.o
  LEX     scripts/kconfig/lexer.lex.c
  YACC    scripts/kconfig/parser.tab.[ch]
  HOSTCC  scripts/kconfig/lexer.lex.o
  HOSTCC  scripts/kconfig/parser.tab.o
  HOSTCC  scripts/kconfig/preprocess.o
  HOSTCC  scripts/kconfig/symbol.o
  HOSTLD  scripts/kconfig/conf

[1] Pattern rule

GNU Make manual says:
"Pattern rules may have more than one target. Unlike normal rules,
this does not act as many different rules with the same prerequisites
and recipe. If a pattern rule has multiple targets, make knows that
the rule's recipe is responsible for making all of the targets. The
recipe is executed only once to make all the targets. When searching
for a pattern rule to match a target, the target patterns of a rule
other than the one that matches the target in need of a rule are
incidental: make worries only about giving a recipe and prerequisites
to the file presently in question. However, when this file's recipe is
run, the other targets are marked as having been updated themselves."

https://www.gnu.org/software/make/manual/html_node/Pattern-Intro.htmlSigned-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

$(basename ...) trims the last suffix. Using it is more intuitive in
my opinion.

This pattern rule makes %.asn1.c and %.asn1.h at the same time.
Previously, the short log showed only either of them, depending on
the target file in question.

To clarify that two files are being generated by the single recipe,
I changed the log as follows:

Before:

  ASN.1   crypto/asymmetric_keys/x509.asn1.c

After:

  ASN.1   crypto/asymmetric_keys/x509.asn1.[ch]
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The gold linker has known issues of failing the build both in random and in
predictible ways:

 - The x86/X32 VDSO build fails with:

   arch/x86/entry/vdso/vclock_gettime-x32.o:vclock_gettime.c:function do_hres:
   error: relocation overflow: reference to 'hvclock_page'

   That's a known issue for years and the usual workaround is to disable
   CONFIG_X86_32

 - A recent build failure is caused by turning a relocation into an
   absolute one for unknown reasons. See link below.

 - There are a couple of gold workarounds applied already, but reports
   about broken builds with ld.gold keep coming in on a regular base and in
   most cases the root cause is unclear.

In context of the most recent fail H.J. stated:

  "Since building a workable kernel for different kernel configurations
   isn't a requirement for gold, I don't recommend gold for kernel."

So instead of dealing with attempts to duct tape gold support without
understanding the root cause and without support from the gold folks, fail
the build when gold is detected.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/CAMe9rOqMqkQ0LNpm25yE_Yt0FKp05WmHOrwc0aRDb53miFKM+w@mail.gmail.comReviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

This patch adds a check to warn about static EXPORT_SYMBOL* functions
during the modpost. In most of the cases, a static symbol marked for
exporting is an odd combination that should be fixed either by deleting
the exporting mark or by removing the static attribute and adding the
appropriate declaration to headers.

This check could help to detect the following problems:
1. 550113d4 ("i2c: add newly exported functions to the header, too")
2. 54638c6e ("net: phy: make exported variables non-static")
3. 98ef2046 ("mm: remove the exporting of totalram_pages")
4. 73df167c ("s390/zcrypt: remove the exporting of ap_query_configuration")
5. a57caf8c ("sunrpc/cache: remove the exporting of cache_seq_next")
6. e4e47306 ("crypto: skcipher - remove the exporting of skcipher_walk_next")
7. 14b4c48b ("gve: Remove the exporting of gve_probe")
8. 9b79ee97 ("scsi: libsas: remove the exporting of sas_wait_eh")
9. ...

The build time impact is very limited and is almost at the unnoticeable
level (< 1 sec).
Acked-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Pull dax fixes from Dan Williams:
 "A filesystem-dax and device-dax fix for v5.3.

  The filesystem-dax fix is tagged for stable as the implementation has
  been mistakenly throwing away all cow pages on any truncate or hole
  punch operation as part of the solution to coordinate device-dma vs
  truncate to dax pages.

  The device-dax change fixes up a regression this cycle from the
  introduction of a common 'internal per-cpu-ref' implementation.

  Summary:

   - Fix dax_layout_busy_page() to not discard private cow pages of
     fs/dax private mappings.

   - Update the memremap_pages core to properly cleanup on behalf of
     internal reference-count users like device-dax"

* tag 'dax-fixes-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  mm/memremap: Fix reuse of pgmap instances with internal references
  dax: dax_layout_busy_page() should not unmap cow pages

Pull NTB fix from Jon Mason:
 "Bug fix for NTB MSI kernel compile warning"

* tag 'ntb-5.3-bugfixes' of git://github.com/jonmason/ntb:
  NTB/msi: remove incorrect MODULE defines

Pull RISC-V updates from Paul Walmsley:
 "A few minor RISC-V updates for v5.3-rc4:

   - Remove __udivdi3() from the 32-bit Linux port, converting the only
     upstream user to use do_div(), per Linux policy

   - Convert the RISC-V standard clocksource away from per-cpu data
     structures, since only one is used by Linux, even on a multi-CPU
     system

   - A set of DT binding updates that remove an obsolete text binding in
     favor of a YAML binding, fix a bogus compatible string in the
     schema (thus fixing a "make dtbs_check" warning), and clarifies the
     future values expected in one of the RISC-V CPU properties"

* tag 'riscv/for-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  dt-bindings: riscv: fix the schema compatible string for the HiFive Unleashed board
  dt-bindings: riscv: remove obsolete cpus.txt
  RISC-V: Remove udivdi3
  riscv: delay: use do_div() instead of __udivdi3()
  dt-bindings: Update the riscv,isa string description
  RISC-V: Remove per cpu clocksource

Pull x86 fixes from Thomas Gleixner:
 "A few fixes for x86:

   - Don't reset the carefully adjusted build flags for the purgatory
     and remove the unwanted flags instead. The 'reset all' approach led
     to build fails under certain circumstances.

   - Unbreak CLANG build of the purgatory by avoiding the builtin
     memcpy/memset implementations.

   - Address missing prototype warnings by including the proper header

   - Fix yet more fall-through issues"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/lib/cpu: Address missing prototypes warning
  x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS
  x86/purgatory: Do not use __builtin_memcpy and __builtin_memset
  x86: mtrr: cyrix: Mark expected switch fall-through
  x86/ptrace: Mark expected switch fall-through

Pull perf tooling fixes from Thomas Gleixner:
 "Perf tooling fixes all over the place:

   - Fix the selection of the main thread COMM in db-export

   - Fix the disassemmbly display for BPF in annotate

   - Fix cpumap mask setup in perf ftrace when only one CPU is present

   - Add the missing 'cpu_clk_unhalted.core' event

   - Fix CPU 0 bindings in NUMA benchmarks

   - Fix the module size calculations for s390

   - Handle the gap between kernel end and module start on s390
     correctly

   - Build and typo fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf pmu-events: Fix missing "cpu_clk_unhalted.core" event
  perf annotate: Fix s390 gap between kernel end and module start
  perf record: Fix module size on s390
  perf tools: Fix include paths in ui directory
  perf tools: Fix a typo in a variable name in the Documentation Makefile
  perf cpumap: Fix writing to illegal memory in handling cpumap mask
  perf ftrace: Fix failure to set cpumask when only one cpu is present
  perf db-export: Fix thread__exec_comm()
  perf annotate: Fix printing of unaugmented disassembled instructions from BPF
  perf bench numa: Fix cpu0 binding

Pull scheduler fixes from Thomas Gleixner:
 "Three fixlets for the scheduler:

   - Avoid double bandwidth accounting in the push & pull code

   - Use a sane FIFO priority for the Pressure Stall Information (PSI)
     thread.

   - Avoid permission checks when setting the scheduler params for the
     PSI thread"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/psi: Do not require setsched permission from the trigger creator
  sched/psi: Reduce psimon FIFO priority
  sched/deadline: Fix double accounting of rq/running bw in push & pull

Pull irq fix from Thomas Gleixner:
 "A small fix for the affinity spreading code.

  It failed to handle situations where a single vector was requested
  either due to only one CPU being available or vector exhaustion
  causing only a single interrupt to be granted.

  The fix is to simply remove the requirement in the affinity spreading
  code for more than one interrupt being available"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/affinity: Create affinity mask for single vector

Pull objtool warning fix from Thomas Gleixner:
 "The recent objtool fixes/enhancements unearthed a unbalanced CLAC in
  the i915 driver.

  Chris asked me to pick the fix up and route it through"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  drm/i915: Remove redundant user_access_end() from __copy_from_user() error path

Pull gfs2 fix from Andreas Gruenbacher:
 "Fix incorrect lseek / fiemap results"

* tag 'gfs2-v5.3-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: gfs2_walk_metadata fix

A compilation -Wimplicit-fallthrough warning was enabled by commit
a035d552 ("Makefile: Globally enable fall-through warning")

Even though clang 10.0.0 does not currently support this warning without
a patch, clang currently does not support a value for this option.

  Link: https://bugs.llvm.org/show_bug.cgi?id=39382

The gcc default for this warning is 3 so removing the =3 has no effect
for gcc and enables the warning for patched versions of clang.

Also remove the =3 from an existing use in a parisc Makefile:
arch/parisc/math-emu/Makefile
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull char/misc driver fixes Greg KH:
 "Here are some small char/misc driver fixes for 5.3-rc4.

  Two of these are for the habanalabs driver for issues found when
  running on a big-endian system (are they still alive?) The others are
  tiny fixes reported by people, and a MAINTAINERS update about the
  location of the fpga development tree.

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

* tag 'char-misc-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  coresight: Fix DEBUG_LOCKS_WARN_ON for uninitialized attribute
  MAINTAINERS: Move linux-fpga tree to new location
  nvmem: Use the same permissions for eeprom as for nvmem
  habanalabs: fix host memory polling in BE architecture
  habanalabs: fix F/W download in BE architecture

Pull driver core fixes from Greg KH:
 "Here are two small fixes for some driver core issues that have been
  reported. There is also a kernfs "fix" here, which was then reverted
  because it was found to cause problems in linux-next.

  The driver core fixes both resolve reported issues, one with gpioint
  stuff that showed up in 5.3-rc1, and the other finally (and hopefully)
  resolves a very long standing race when removing glue directories.
  It's nice to get that issue finally resolved and the developers
  involved should be applauded for the persistence it took to get this
  patch finally accepted.

  All of these have been in linux-next for a while with no reported
  issues. Well, the one reported issue, hence the revert :)"

* tag 'driver-core-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Revert "kernfs: fix memleak in kernel_ops_readdir()"
  kernfs: fix memleak in kernel_ops_readdir()
  driver core: Fix use-after-free and double free on glue directory
  driver core: platform: return -ENXIO for missing GpioInt

Pull tty fix from Greg KH:
 "Here is a single tty kgdb fix for 5.3-rc4.

  It fixes an annoying log message that has caused kdb to become
  useless. It's another fallout from commit ddde3c18 ("vt: More
  locking checks") which tries to enforce locking checks more strictly
  in the tty layer, unfortunatly when kdb is stopped, there's no need
  for locks :)

  This patch has been linux-next for a while with no reported issues"

* tag 'tty-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  kgdboc: disable the console lock when in kgdb

Pull staging / IIO driver fixes from Greg KH:
 "Here are some small staging and IIO driver fixes for 5.3-rc4.

  Nothing major, just resolutions for a number of small reported issues,
  full details in the shortlog.

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

* tag 'staging-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  iio: adc: gyroadc: fix uninitialized return code
  docs: generic-counter.rst: fix broken references for ABI file
  staging: android: ion: Bail out upon SIGKILL when allocating memory.
  Staging: fbtft: Fix GPIO handling
  staging: unisys: visornic: Update the description of 'poll_for_irq()'
  staging: wilc1000: flush the workqueue before deinit the host
  staging: gasket: apex: fix copy-paste typo
  Staging: fbtft: Fix reset assertion when using gpio descriptor
  Staging: fbtft: Fix probing of gpio descriptor
  iio: imu: mpu6050: add missing available scan masks
  iio: cros_ec_accel_legacy: Fix incorrect channel setting
  IIO: Ingenic JZ47xx: Set clock divider on probe
  iio: adc: max9611: Fix misuse of GENMASK macro

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for 5.3-rc4.

  The "biggest" one here is moving code from one file to another in
  order to fix a long-standing race condition with the creation of sysfs
  files for USB devices. Turns out that there are now userspace tools
  out there that are hitting this long-known bug, so it's time to fix
  them. Thankfully the tool-maker in this case fixed the issue :)

  The other patches in here are all fixes for reported issues. Now that
  syzbot knows how to fuzz USB drivers better, and is starting to now
  fuzz the userspace facing side of them at the same time, there will be
  more and more small fixes like these coming, which is a good thing.

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

* tag 'usb-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: setup authorized_default attributes using usb_bus_notify
  usb: iowarrior: fix deadlock on disconnect
  Revert "USB: rio500: simplify locking"
  usb: usbfs: fix double-free of usb memory upon submiturb error
  usb: yurex: Fix use-after-free in yurex_delete
  usb: typec: tcpm: Ignore unsupported/unknown alternate mode requests
  xhci: Fix NULL pointer dereference at endpoint zero reset.
  usb: host: xhci-rcar: Fix timeout in xhci_suspend()
  usb: typec: ucsi: ccg: Fix uninitilized symbol error
  usb: typec: tcpm: remove tcpm dir if no children
  usb: typec: tcpm: free log buf memory when remove debug file
  usb: typec: tcpm: Add NULL check before dereferencing config

Pull pin control fixes from Linus Walleij:

 - Delay acquisition of regmaps in the Aspeed G5 driver.

 - Make a symbol static to reduce compiler noise.

* tag 'pinctrl-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: aspeed: Make aspeed_pinmux_ips static
  pinctrl: aspeed-g5: Delay acquisition of regmaps

Pull powerpc fix from Michael Ellerman:
 "Just one fix, a revert of a commit that was meant to be a minor
  improvement to some inline asm, but ended up having no real benefit
  with GCC and broke booting 32-bit machines when using Clang.

  Thanks to: Arnd Bergmann, Christophe Leroy, Nathan Chancellor, Nick
  Desaulniers, Segher Boessenkool"

* tag 'powerpc-5.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  Revert "powerpc: slightly improve cache helpers"

Merge tag 'Wimplicit-fallthrough-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull fall-through fixes from Gustavo A. R. Silva:
 "Mark more switch cases where we are expecting to fall through, fixing
  fall-through warnings in arm, sparc64, mips, i386 and s390"

* tag 'Wimplicit-fallthrough-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  ARM: ep93xx: Mark expected switch fall-through
  scsi: fas216: Mark expected switch fall-throughs
  pcmcia: db1xxx_ss: Mark expected switch fall-throughs
  video: fbdev: omapfb_main: Mark expected switch fall-throughs
  watchdog: riowd: Mark expected switch fall-through
  s390/net: Mark expected switch fall-throughs
  crypto: ux500/crypt: Mark expected switch fall-throughs
  watchdog: wdt977: Mark expected switch fall-through
  watchdog: scx200_wdt: Mark expected switch fall-through
  watchdog: Mark expected switch fall-throughs
  ARM: signal: Mark expected switch fall-through
  mfd: omap-usb-host: Mark expected switch fall-throughs
  mfd: db8500-prcmu: Mark expected switch fall-throughs
  ARM: OMAP: dma: Mark expected switch fall-throughs
  ARM: alignment: Mark expected switch fall-throughs
  ARM: tegra: Mark expected switch fall-through
  ARM/hw_breakpoint: Mark expected switch fall-throughs

Merge tag 'kbuild-fixes-v5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - revive single target %.ko

 - do not create built-in.a where it is unneeded

 - do not create modules.order where it is unneeded

 - show a warning if subdir-y/m is used to visit a module Makefile

* tag 'kbuild-fixes-v5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: show hint if subdir-y/m is used to visit module Makefile
  kbuild: generate modules.order only in directories visited by obj-y/m
  kbuild: fix false-positive need-builtin calculation
  kbuild: revive single target %.ko

Mark switch cases where we are expecting to fall through.

Fix the following warnings (Building: arm-ep93xx_defconfig arm):

arch/arm/mach-ep93xx/crunch.c: In function 'crunch_do':
arch/arm/mach-ep93xx/crunch.c:46:3: warning: this statement may
fall through [-Wimplicit-fallthrough=]
      memset(crunch_state, 0, sizeof(*crunch_state));
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/arm/mach-ep93xx/crunch.c:53:2: note: here
     case THREAD_NOTIFY_EXIT:
     ^~~~

Notice that, in this particular case, the code comment is
modified in accordance with what GCC is expecting to find.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Mark switch cases where we are expecting to fall through.

Fix the following warnings (Building: rpc_defconfig arm):

drivers/scsi/arm/fas216.c: In function ‘fas216_disconnect_intr’:
drivers/scsi/arm/fas216.c:913:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
   if (fas216_get_last_msg(info, info->scsi.msgin_fifo) == ABORT) {
      ^
drivers/scsi/arm/fas216.c:919:2: note: here
  default:    /* huh?     */
  ^~~~~~~
drivers/scsi/arm/fas216.c: In function ‘fas216_kick’:
drivers/scsi/arm/fas216.c:1959:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
   fas216_allocate_tag(info, SCpnt);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/arm/fas216.c:1960:2: note: here
  case TYPE_OTHER:
  ^~~~
drivers/scsi/arm/fas216.c: In function ‘fas216_busservice_intr’:
drivers/scsi/arm/fas216.c:1413:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
   fas216_stoptransfer(info);
   ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/arm/fas216.c:1414:2: note: here
  case STATE(STAT_STATUS, PHASE_SELSTEPS):/* Sel w/ steps -> Status       */
  ^~~~
drivers/scsi/arm/fas216.c:1424:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
   fas216_stoptransfer(info);
   ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/arm/fas216.c:1425:2: note: here
  case STATE(STAT_MESGIN, PHASE_COMMAND): /* Command -> Message In */
  ^~~~
drivers/scsi/arm/fas216.c: In function ‘fas216_funcdone_intr’:
drivers/scsi/arm/fas216.c:1573:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
   if ((stat & STAT_BUSMASK) == STAT_MESGIN) {
      ^
drivers/scsi/arm/fas216.c:1579:2: note: here
  default:
  ^~~~~~~
drivers/scsi/arm/fas216.c: In function ‘fas216_handlesync’:
drivers/scsi/arm/fas216.c:605:20: warning: this statement may fall through [-Wimplicit-fallthrough=]
   info->scsi.phase = PHASE_MSGOUT_EXPECT;
   ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
drivers/scsi/arm/fas216.c:607:2: note: here
  case async:
  ^~~~
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Mark switch cases where we are expecting to fall through.

This patch fixes the following warnings (Building: db1xxx_defconfig mips):

drivers/pcmcia/db1xxx_ss.c:257:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/pcmcia/db1xxx_ss.c:269:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>