Merge branch 'akpm' (patches from Andrew)

Merge misc Kconfig updates from Andrew Morton:
 "A number of changes to Kconfig files under lib/ from Changbin Du and
  Krzysztof Kozlowski"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib/: fix Kconfig indentation
  kernel-hacking: move DEBUG_FS to 'Generic Kernel Debugging Instruments'
  kernel-hacking: move DEBUG_BUGVERBOSE to 'printk and dmesg options'
  kernel-hacking: create a submenu for scheduler debugging options
  kernel-hacking: move SCHED_STACK_END_CHECK after DEBUG_STACK_USAGE
  kernel-hacking: move Oops into 'Lockups and Hangs'
  kernel-hacking: move kernel testing and coverage options to same submenu
  kernel-hacking: group kernel data structures debugging together
  kernel-hacking: create submenu for arch special debugging options
  kernel-hacking: group sysrq/kgdb/ubsan into 'Generic Kernel Debugging Instruments'

3 files changed, 199 insertions, 178 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 6d7c5877c9f1..6e790dc55c5b 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -572,7 +572,7 @@ config OID_REGISTRY
 	  Enable fast lookup object identifier registry.
 
 config UCS2_STRING
-        tristate
+	tristate
 
 #
 # generic vdso
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 2f6fb96405af..d1842fe756d5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -128,8 +128,8 @@ config DYNAMIC_DEBUG
 	  lineno : line number of the debug statement
 	  module : module that contains the debug statement
 	  function : function that contains the debug statement
-          flags : '=p' means the line is turned 'on' for printing
-          format : the format used for the debug statement
+	  flags : '=p' means the line is turned 'on' for printing
+	  format : the format used for the debug statement
 
 	  From a live system:
 
@@ -173,6 +173,15 @@ config SYMBOLIC_ERRNAME
 	  of the number 28. It makes the kernel image slightly larger
 	  (about 3KB), but can make the kernel logs easier to read.
 
+config DEBUG_BUGVERBOSE
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE)
+	default y
+	help
+	  Say Y here to make BUG() panics output the file name and line number
+	  of the BUG call as well as the EIP and oops trace.  This aids
+	  debugging but costs about 70-100K of memory.
+
 endmenu # "printk and dmesg options"
 
 menu "Compile-time checks and compiler options"
@@ -181,7 +190,7 @@ config DEBUG_INFO
 	bool "Compile the kernel with debug info"
 	depends on DEBUG_KERNEL && !COMPILE_TEST
 	help
-          If you say Y here the resulting kernel image will include
+	  If you say Y here the resulting kernel image will include
 	  debugging info resulting in a larger kernel image.
 	  This adds debug symbols to the kernel and modules (gcc -g), and
 	  is needed if you intend to use kernel crashdump or binary object
@@ -278,25 +287,13 @@ config STRIP_ASM_SYMS
 	  get_wchan() and suchlike.
 
 config READABLE_ASM
-        bool "Generate readable assembler code"
-        depends on DEBUG_KERNEL
-        help
-          Disable some compiler optimizations that tend to generate human unreadable
-          assembler output. This may make the kernel slightly slower, but it helps
-          to keep kernel developers who have to stare a lot at assembler listings
-          sane.
-
-config DEBUG_FS
-	bool "Debug Filesystem"
+	bool "Generate readable assembler code"
+	depends on DEBUG_KERNEL
 	help
-	  debugfs is a virtual file system that kernel developers use to put
-	  debugging files into.  Enable this option to be able to read and
-	  write to these files.
-
-	  For detailed documentation on the debugfs API, see
-	  Documentation/filesystems/.
-
-	  If unsure, say N.
+	  Disable some compiler optimizations that tend to generate human unreadable
+	  assembler output. This may make the kernel slightly slower, but it helps
+	  to keep kernel developers who have to stare a lot at assembler listings
+	  sane.
 
 config HEADERS_INSTALL
 	bool "Install uapi headers to usr/include"
@@ -399,6 +396,8 @@ config DEBUG_FORCE_WEAK_PER_CPU
 
 endmenu # "Compiler options"
 
+menu "Generic Kernel Debugging Instruments"
+
 config MAGIC_SYSRQ
 	bool "Magic SysRq key"
 	depends on !UML
@@ -432,6 +431,24 @@ config MAGIC_SYSRQ_SERIAL
 	  This option allows you to decide whether you want to enable the
 	  magic SysRq key.
 
+config DEBUG_FS
+	bool "Debug Filesystem"
+	help
+	  debugfs is a virtual file system that kernel developers use to put
+	  debugging files into.  Enable this option to be able to read and
+	  write to these files.
+
+	  For detailed documentation on the debugfs API, see
+	  Documentation/filesystems/.
+
+	  If unsure, say N.
+
+source "lib/Kconfig.kgdb"
+
+source "lib/Kconfig.ubsan"
+
+endmenu
+
 config DEBUG_KERNEL
 	bool "Kernel debugging"
 	help
@@ -506,11 +523,11 @@ config DEBUG_OBJECTS_PERCPU_COUNTER
 
 config DEBUG_OBJECTS_ENABLE_DEFAULT
 	int "debug_objects bootup default value (0-1)"
-        range 0 1
-        default "1"
-        depends on DEBUG_OBJECTS
-        help
-          Debug objects boot parameter default value
+	range 0 1
+	default "1"
+	depends on DEBUG_OBJECTS
+	help
+	  Debug objects boot parameter default value
 
 config DEBUG_SLAB
 	bool "Debug slab memory allocations"
@@ -624,12 +641,24 @@ config DEBUG_STACK_USAGE
 
 	  This option will slow down process creation somewhat.
 
+config SCHED_STACK_END_CHECK
+	bool "Detect stack corruption on calls to schedule()"
+	depends on DEBUG_KERNEL
+	default n
+	help
+	  This option checks for a stack overrun on calls to schedule().
+	  If the stack end location is found to be over written always panic as
+	  the content of the corrupted region can no longer be trusted.
+	  This is to ensure no erroneous behaviour occurs which could result in
+	  data corruption or a sporadic crash at a later stage once the region
+	  is examined. The runtime overhead introduced is minimal.
+
 config DEBUG_VM
 	bool "Debug VM"
 	depends on DEBUG_KERNEL
 	help
 	  Enable this to turn on extended checks in the virtual-memory system
-          that may impact performance.
+	  that may impact performance.
 
 	  If unsure, say N.
 
@@ -756,53 +785,6 @@ source "lib/Kconfig.kasan"
 
 endmenu # "Memory Debugging"
 
-config ARCH_HAS_KCOV
-	bool
-	help
-	  An architecture should select this when it can successfully
-	  build and run with CONFIG_KCOV. This typically requires
-	  disabling instrumentation for some early boot code.
-
-config CC_HAS_SANCOV_TRACE_PC
-	def_bool $(cc-option,-fsanitize-coverage=trace-pc)
-
-config KCOV
-	bool "Code coverage for fuzzing"
-	depends on ARCH_HAS_KCOV
-	depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
-	select DEBUG_FS
-	select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
-	help
-	  KCOV exposes kernel code coverage information in a form suitable
-	  for coverage-guided fuzzing (randomized testing).
-
-	  If RANDOMIZE_BASE is enabled, PC values will not be stable across
-	  different machines and across reboots. If you need stable PC values,
-	  disable RANDOMIZE_BASE.
-
-	  For more details, see Documentation/dev-tools/kcov.rst.
-
-config KCOV_ENABLE_COMPARISONS
-	bool "Enable comparison operands collection by KCOV"
-	depends on KCOV
-	depends on $(cc-option,-fsanitize-coverage=trace-cmp)
-	help
-	  KCOV also exposes operands of every comparison in the instrumented
-	  code along with operand sizes and PCs of the comparison instructions.
-	  These operands can be used by fuzzing engines to improve the quality
-	  of fuzzing coverage.
-
-config KCOV_INSTRUMENT_ALL
-	bool "Instrument all code by default"
-	depends on KCOV
-	default y
-	help
-	  If you are doing generic system call fuzzing (like e.g. syzkaller),
-	  then you will want to instrument the whole kernel and you should
-	  say y here. If you are doing more targeted fuzzing (like e.g.
-	  filesystem fuzzing with AFL) then you will want to enable coverage
-	  for more specific subsets of files, and should say n here.
-
 config DEBUG_SHIRQ
 	bool "Debug shared IRQ handlers"
 	depends on DEBUG_KERNEL
@@ -812,7 +794,35 @@ config DEBUG_SHIRQ
 	  Drivers ought to be able to handle interrupts coming in at those
 	  points; some don't and need to be caught.
 
-menu "Debug Lockups and Hangs"
+menu "Debug Oops, Lockups and Hangs"
+
+config PANIC_ON_OOPS
+	bool "Panic on Oops"
+	help
+	  Say Y here to enable the kernel to panic when it oopses. This
+	  has the same effect as setting oops=panic on the kernel command
+	  line.
+
+	  This feature is useful to ensure that the kernel does not do
+	  anything erroneous after an oops which could result in data
+	  corruption or other issues.
+
+	  Say N if unsure.
+
+config PANIC_ON_OOPS_VALUE
+	int
+	range 0 1
+	default 0 if !PANIC_ON_OOPS
+	default 1 if PANIC_ON_OOPS
+
+config PANIC_TIMEOUT
+	int "panic timeout"
+	default 0
+	help
+	  Set the timeout value (in seconds) until a reboot occurs when the
+	  the kernel panics. If n = 0, then we wait forever. A timeout
+	  value n > 0 will wait n seconds before rebooting, while a timeout
+	  value n < 0 will reboot immediately.
 
 config LOCKUP_DETECTOR
 	bool
@@ -970,33 +980,7 @@ config WQ_WATCHDOG
 
 endmenu # "Debug lockups and hangs"
 
-config PANIC_ON_OOPS
-	bool "Panic on Oops"
-	help
-	  Say Y here to enable the kernel to panic when it oopses. This
-	  has the same effect as setting oops=panic on the kernel command
-	  line.
-
-	  This feature is useful to ensure that the kernel does not do
-	  anything erroneous after an oops which could result in data
-	  corruption or other issues.
-
-	  Say N if unsure.
-
-config PANIC_ON_OOPS_VALUE
-	int
-	range 0 1
-	default 0 if !PANIC_ON_OOPS
-	default 1 if PANIC_ON_OOPS
-
-config PANIC_TIMEOUT
-	int "panic timeout"
-	default 0
-	help
-	  Set the timeout value (in seconds) until a reboot occurs when the
-	  the kernel panics. If n = 0, then we wait forever. A timeout
-	  value n > 0 will wait n seconds before rebooting, while a timeout
-	  value n < 0 will reboot immediately.
+menu "Scheduler Debugging"
 
 config SCHED_DEBUG
 	bool "Collect scheduler debugging info"
@@ -1024,17 +1008,7 @@ config SCHEDSTATS
 	  application, you can say N to avoid the very slight overhead
 	  this adds.
 
-config SCHED_STACK_END_CHECK
-	bool "Detect stack corruption on calls to schedule()"
-	depends on DEBUG_KERNEL
-	default n
-	help
-	  This option checks for a stack overrun on calls to schedule().
-	  If the stack end location is found to be over written always panic as
-	  the content of the corrupted region can no longer be trusted.
-	  This is to ensure no erroneous behaviour occurs which could result in
-	  data corruption or a sporadic crash at a later stage once the region
-	  is examined. The runtime overhead introduced is minimal.
+endmenu
 
 config DEBUG_TIMEKEEPING
 	bool "Enable extra timekeeping sanity checking"
@@ -1338,14 +1312,7 @@ config DEBUG_KOBJECT_RELEASE
 config HAVE_DEBUG_BUGVERBOSE
 	bool
 
-config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
-	depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE)
-	default y
-	help
-	  Say Y here to make BUG() panics output the file name and line number
-	  of the BUG call as well as the EIP and oops trace.  This aids
-	  debugging but costs about 70-100K of memory.
+menu "Debug kernel data structures"
 
 config DEBUG_LIST
 	bool "Debug linked list manipulation"
@@ -1386,6 +1353,18 @@ config DEBUG_NOTIFIERS
 	  This is a relatively cheap check but if you care about maximum
 	  performance, say N.
 
+config BUG_ON_DATA_CORRUPTION
+	bool "Trigger a BUG when data corruption is detected"
+	select DEBUG_LIST
+	help
+	  Select this option if the kernel should BUG when it encounters
+	  data corruption in kernel memory structures when they get checked
+	  for validity.
+
+	  If unsure, say N.
+
+endmenu
+
 config DEBUG_CREDENTIALS
 	bool "Debug credential management"
 	depends on DEBUG_KERNEL
@@ -1419,7 +1398,7 @@ config DEBUG_WQ_FORCE_RR_CPU
 	  be impacted.
 
 config DEBUG_BLOCK_EXT_DEVT
-        bool "Force extended block device numbers and spread them"
+	bool "Force extended block device numbers and spread them"
 	depends on DEBUG_KERNEL
 	depends on BLOCK
 	default n
@@ -1458,6 +1437,54 @@ config CPU_HOTPLUG_STATE_CONTROL
 
 	  Say N if your are unsure.
 
+config LATENCYTOP
+	bool "Latency measuring infrastructure"
+	depends on DEBUG_KERNEL
+	depends on STACKTRACE_SUPPORT
+	depends on PROC_FS
+	select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM && !ARC && !X86
+	select KALLSYMS
+	select KALLSYMS_ALL
+	select STACKTRACE
+	select SCHEDSTATS
+	select SCHED_DEBUG
+	help
+	  Enable this option if you want to use the LatencyTOP tool
+	  to find out which userspace is blocking on what kernel operations.
+
+source "kernel/trace/Kconfig"
+
+config PROVIDE_OHCI1394_DMA_INIT
+	bool "Remote debugging over FireWire early on boot"
+	depends on PCI && X86
+	help
+	  If you want to debug problems which hang or crash the kernel early
+	  on boot and the crashing machine has a FireWire port, you can use
+	  this feature to remotely access the memory of the crashed machine
+	  over FireWire. This employs remote DMA as part of the OHCI1394
+	  specification which is now the standard for FireWire controllers.
+
+	  With remote DMA, you can monitor the printk buffer remotely using
+	  firescope and access all memory below 4GB using fireproxy from gdb.
+	  Even controlling a kernel debugger is possible using remote DMA.
+
+	  Usage:
+
+	  If ohci1394_dma=early is used as boot parameter, it will initialize
+	  all OHCI1394 controllers which are found in the PCI config space.
+
+	  As all changes to the FireWire bus such as enabling and disabling
+	  devices cause a bus reset and thereby disable remote DMA for all
+	  devices, be sure to have the cable plugged and FireWire enabled on
+	  the debugging host before booting the debug target for debugging.
+
+	  This code (~1k) is freed after boot. By then, the firewire stack
+	  in charge of the OHCI-1394 controllers should be used instead.
+
+	  See Documentation/debugging-via-ohci1394.txt for more information.
+
+source "lib/kunit/Kconfig"
+
 config NOTIFIER_ERROR_INJECTION
 	tristate "Notifier error injection"
 	depends on DEBUG_KERNEL
@@ -1616,53 +1643,57 @@ config FAULT_INJECTION_STACKTRACE_FILTER
 	help
 	  Provide stacktrace filter for fault-injection capabilities
 
-config LATENCYTOP
-	bool "Latency measuring infrastructure"
-	depends on DEBUG_KERNEL
-	depends on STACKTRACE_SUPPORT
-	depends on PROC_FS
-	select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM && !ARC && !X86
-	select KALLSYMS
-	select KALLSYMS_ALL
-	select STACKTRACE
-	select SCHEDSTATS
-	select SCHED_DEBUG
-	help
-	  Enable this option if you want to use the LatencyTOP tool
-	  to find out which userspace is blocking on what kernel operations.
+endmenu # "Kernel Testing and Coverage"
 
-source "kernel/trace/Kconfig"
+menu "Kernel Testing and Coverage"
 
-config PROVIDE_OHCI1394_DMA_INIT
-	bool "Remote debugging over FireWire early on boot"
-	depends on PCI && X86
+config ARCH_HAS_KCOV
+	bool
 	help
-	  If you want to debug problems which hang or crash the kernel early
-	  on boot and the crashing machine has a FireWire port, you can use
-	  this feature to remotely access the memory of the crashed machine
-	  over FireWire. This employs remote DMA as part of the OHCI1394
-	  specification which is now the standard for FireWire controllers.
+	  An architecture should select this when it can successfully
+	  build and run with CONFIG_KCOV. This typically requires
+	  disabling instrumentation for some early boot code.
 
-	  With remote DMA, you can monitor the printk buffer remotely using
-	  firescope and access all memory below 4GB using fireproxy from gdb.
-	  Even controlling a kernel debugger is possible using remote DMA.
+config CC_HAS_SANCOV_TRACE_PC
+	def_bool $(cc-option,-fsanitize-coverage=trace-pc)
 
-	  Usage:
 
-	  If ohci1394_dma=early is used as boot parameter, it will initialize
-	  all OHCI1394 controllers which are found in the PCI config space.
+config KCOV
+	bool "Code coverage for fuzzing"
+	depends on ARCH_HAS_KCOV
+	depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
+	select DEBUG_FS
+	select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
+	help
+	  KCOV exposes kernel code coverage information in a form suitable
+	  for coverage-guided fuzzing (randomized testing).
 
-	  As all changes to the FireWire bus such as enabling and disabling
-	  devices cause a bus reset and thereby disable remote DMA for all
-	  devices, be sure to have the cable plugged and FireWire enabled on
-	  the debugging host before booting the debug target for debugging.
+	  If RANDOMIZE_BASE is enabled, PC values will not be stable across
+	  different machines and across reboots. If you need stable PC values,
+	  disable RANDOMIZE_BASE.
 
-	  This code (~1k) is freed after boot. By then, the firewire stack
-	  in charge of the OHCI-1394 controllers should be used instead.
+	  For more details, see Documentation/dev-tools/kcov.rst.
 
-	  See Documentation/debugging-via-ohci1394.txt for more information.
+config KCOV_ENABLE_COMPARISONS
+	bool "Enable comparison operands collection by KCOV"
+	depends on KCOV
+	depends on $(cc-option,-fsanitize-coverage=trace-cmp)
+	help
+	  KCOV also exposes operands of every comparison in the instrumented
+	  code along with operand sizes and PCs of the comparison instructions.
+	  These operands can be used by fuzzing engines to improve the quality
+	  of fuzzing coverage.
 
-source "lib/kunit/Kconfig"
+config KCOV_INSTRUMENT_ALL
+	bool "Instrument all code by default"
+	depends on KCOV
+	default y
+	help
+	  If you are doing generic system call fuzzing (like e.g. syzkaller),
+	  then you will want to instrument the whole kernel and you should
+	  say y here. If you are doing more targeted fuzzing (like e.g.
+	  filesystem fuzzing with AFL) then you will want to enable coverage
+	  for more specific subsets of files, and should say n here.
 
 menuconfig RUNTIME_TESTING_MENU
 	bool "Runtime Testing"
@@ -2099,22 +2130,8 @@ config MEMTEST
 	        memtest=17, mean do 17 test patterns.
 	  If you are unsure how to answer this question, answer N.
 
-config BUG_ON_DATA_CORRUPTION
-	bool "Trigger a BUG when data corruption is detected"
-	select DEBUG_LIST
-	help
-	  Select this option if the kernel should BUG when it encounters
-	  data corruption in kernel memory structures when they get checked
-	  for validity.
-
-	  If unsure, say N.
-
 source "samples/Kconfig"
 
-source "lib/Kconfig.kgdb"
-
-source "lib/Kconfig.ubsan"
-
 config ARCH_HAS_DEVMEM_IS_ALLOWED
 	bool
 
@@ -2154,8 +2171,12 @@ config IO_STRICT_DEVMEM
 
 	  If in doubt, say Y.
 
+menu "$(SRCARCH) Debugging"
+
 source "arch/$(SRCARCH)/Kconfig.debug"
 
+endmenu
+
 config HYPERV_TESTING
 	bool "Microsoft Hyper-V driver testing"
 	default n
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index bbe397df04a3..933680b59e2d 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -64,9 +64,9 @@ config KGDB_LOW_LEVEL_TRAP
        depends on X86 || MIPS
        default n
        help
-         This will add an extra call back to kgdb for the breakpoint
-         exception handler which will allow kgdb to step through a
-         notify handler.
+	 This will add an extra call back to kgdb for the breakpoint
+	 exception handler which will allow kgdb to step through a
+	 notify handler.
 
 config KGDB_KDB
 	bool "KGDB_KDB: include kdb frontend for kgdb"
@@ -96,7 +96,7 @@ config KDB_DEFAULT_ENABLE
 
 	  The config option merely sets the default at boot time. Both
 	  issuing 'echo X > /sys/module/kdb/parameters/cmd_enable' or
-          setting with kdb.cmd_enable=X kernel command line option will
+	  setting with kdb.cmd_enable=X kernel command line option will
 	  override the default settings.
 
 config KDB_KEYBOARD