Merge branch 'mm-nonmm-unstable' into mm-everything

CREDITS

@@ -1848,11 +1848,11 @@ E: ajoshi@shell.unixbox.com
 D: fbdev hacking
 
 N: Jesper Juhl
-E: jj@chaosbits.net
+E: jesperjuhl76@gmail.com
 D: Various fixes, cleanups and minor features all over the tree.
 D: Wrote initial version of the hdaps driver (since passed on to others).
-S: Lemnosvej 1, 3.tv
-S: 2300 Copenhagen S.
+S: Titangade 5G, 2.tv
+S: 2200 Copenhagen N.
 S: Denmark
 
 N: Jozsef Kadlecsik

Documentation/accounting/delay-accounting.rst

@@ -109,17 +109,17 @@ Get sum of delays, since system boot, for all pids with tgid 5::
 	CPU             count     real total  virtual total    delay total  delay average
 	                    8        7000000        6872122        3382277          0.423ms
 	IO              count    delay total  delay average
-		            0              0              0ms
+                   0              0          0.000ms
 	SWAP            count    delay total  delay average
-	                    0              0              0ms
+                       0              0          0.000ms
 	RECLAIM         count    delay total  delay average
-		            0              0              0ms
+                   0              0          0.000ms
 	THRASHING       count    delay total  delay average
-	                    0              0              0ms
+                       0              0          0.000ms
 	COMPACT         count    delay total  delay average
-	                    0              0              0ms
-        WPCOPY          count    delay total  delay average
-                            0              0              0ms
+                       0              0          0.000ms
+   WPCOPY          count    delay total  delay average
+                       0              0          0.000ms
 
 Get IO accounting for pid 1, it works only with -p::
 

Documentation/admin-guide/sysctl/kernel.rst

@@ -453,16 +453,35 @@ this allows system administrators to override the
 kexec_load_disabled
 ===================
 
-A toggle indicating if the ``kexec_load`` syscall has been disabled.
-This value defaults to 0 (false: ``kexec_load`` enabled), but can be
-set to 1 (true: ``kexec_load`` disabled).
+A toggle indicating if the syscalls ``kexec_load`` and
+``kexec_file_load`` have been disabled.
+This value defaults to 0 (false: ``kexec_*load`` enabled), but can be
+set to 1 (true: ``kexec_*load`` disabled).
 Once true, kexec can no longer be used, and the toggle cannot be set
 back to false.
 This allows a kexec image to be loaded before disabling the syscall,
 allowing a system to set up (and later use) an image without it being
 altered.
 Generally used together with the `modules_disabled`_ sysctl.
 
+kexec_load_limit_panic
+======================
+
+This parameter specifies a limit to the number of times the syscalls
+``kexec_load`` and ``kexec_file_load`` can be called with a crash
+image. It can only be set with a more restrictive value than the
+current one.
+
+== ======================================================
+-1 Unlimited calls to kexec. This is the default setting.
+N  Number of calls left.
+== ======================================================
+
+kexec_load_limit_reboot
+=======================
+
+Similar functionality as ``kexec_load_limit_panic``, but for a normal
+image.
 
 kptr_restrict
 =============

Documentation/fault-injection/fault-injection.rst

@@ -231,6 +231,71 @@ proc entries
 	This feature is intended for systematic testing of faults in a single
 	system call. See an example below.
 
+
+Error Injectable Functions
+--------------------------
+
+This part is for the kenrel developers considering to add a function to
+ALLOW_ERROR_INJECTION() macro.
+
+Requirements for the Error Injectable Functions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Since the function-level error injection forcibly changes the code path
+and returns an error even if the input and conditions are proper, this can
+cause unexpected kernel crash if you allow error injection on the function
+which is NOT error injectable. Thus, you (and reviewers) must ensure;
+
+- The function returns an error code if it fails, and the callers must check
+  it correctly (need to recover from it).
+
+- The function does not execute any code which can change any state before
+  the first error return. The state includes global or local, or input
+  variable. For example, clear output address storage (e.g. `*ret = NULL`),
+  increments/decrements counter, set a flag, preempt/irq disable or get
+  a lock (if those are recovered before returning error, that will be OK.)
+
+The first requirement is important, and it will result in that the release
+(free objects) functions are usually harder to inject errors than allocate
+functions. If errors of such release functions are not correctly handled
+it will cause a memory leak easily (the caller will confuse that the object
+has been released or corrupted.)
+
+The second one is for the caller which expects the function should always
+does something. Thus if the function error injection skips whole of the
+function, the expectation is betrayed and causes an unexpected error.
+
+Type of the Error Injectable Functions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Each error injectable functions will have the error type specified by the
+ALLOW_ERROR_INJECTION() macro. You have to choose it carefully if you add
+a new error injectable function. If the wrong error type is chosen, the
+kernel may crash because it may not be able to handle the error.
+There are 4 types of errors defined in include/asm-generic/error-injection.h
+
+EI_ETYPE_NULL
+  This function will return `NULL` if it fails. e.g. return an allocateed
+  object address.
+
+EI_ETYPE_ERRNO
+  This function will return an `-errno` error code if it fails. e.g. return
+  -EINVAL if the input is wrong. This will include the functions which will
+  return an address which encodes `-errno` by ERR_PTR() macro.
+
+EI_ETYPE_ERRNO_NULL
+  This function will return an `-errno` or `NULL` if it fails. If the caller
+  of this function checks the return value with IS_ERR_OR_NULL() macro, this
+  type will be appropriate.
+
+EI_ETYPE_TRUE
+  This function will return `true` (non-zero positive value) if it fails.
+
+If you specifies a wrong type, for example, EI_TYPE_ERRNO for the function
+which returns an allocated object, it may cause a problem because the returned
+value is not an object address and the caller can not access to the address.
+
+
 How to add new fault injection capability
 -----------------------------------------
 

Documentation/translations/zh_CN/accounting/delay-accounting.rst

@@ -91,15 +91,15 @@ getdelays命令的一般格式::
 	CPU             count     real total  virtual total    delay total  delay average
 	                    8        7000000        6872122        3382277          0.423ms
 	IO              count    delay total  delay average
-	                    0              0              0ms
+	                    0              0              0.000ms
 	SWAP            count    delay total  delay average
-	                    0              0              0ms
+	                    0              0              0.000ms
 	RECLAIM         count    delay total  delay average
-	                    0              0              0ms
+	                    0              0              0.000ms
 	THRASHING       count    delay total  delay average
-	                    0              0              0ms
+	                    0              0              0.000ms
 	COMPACT         count    delay total  delay average
-	                    0              0              0ms
+	                    0              0              0.000ms
 
 获取pid为1的IO计数，它只和-p一起使用::
 	# ./getdelays -i -p 1

arch/Kconfig

@@ -35,7 +35,7 @@ config HOTPLUG_SMT
 	bool
 
 config GENERIC_ENTRY
-       bool
+	bool
 
 config KPROBES
 	bool "Kprobes"
@@ -55,26 +55,26 @@ config JUMP_LABEL
 	depends on HAVE_ARCH_JUMP_LABEL
 	select OBJTOOL if HAVE_JUMP_LABEL_HACK
 	help
-	 This option enables a transparent branch optimization that
-	 makes certain almost-always-true or almost-always-false branch
-	 conditions even cheaper to execute within the kernel.
+	  This option enables a transparent branch optimization that
+	  makes certain almost-always-true or almost-always-false branch
+	  conditions even cheaper to execute within the kernel.
 
-	 Certain performance-sensitive kernel code, such as trace points,
-	 scheduler functionality, networking code and KVM have such
-	 branches and include support for this optimization technique.
+	  Certain performance-sensitive kernel code, such as trace points,
+	  scheduler functionality, networking code and KVM have such
+	  branches and include support for this optimization technique.
 
-	 If it is detected that the compiler has support for "asm goto",
-	 the kernel will compile such branches with just a nop
-	 instruction. When the condition flag is toggled to true, the
-	 nop will be converted to a jump instruction to execute the
-	 conditional block of instructions.
+	  If it is detected that the compiler has support for "asm goto",
+	  the kernel will compile such branches with just a nop
+	  instruction. When the condition flag is toggled to true, the
+	  nop will be converted to a jump instruction to execute the
+	  conditional block of instructions.
 
-	 This technique lowers overhead and stress on the branch prediction
-	 of the processor and generally makes the kernel faster. The update
-	 of the condition is slower, but those are always very rare.
+	  This technique lowers overhead and stress on the branch prediction
+	  of the processor and generally makes the kernel faster. The update
+	  of the condition is slower, but those are always very rare.
 
-	 ( On 32-bit x86, the necessary options added to the compiler
-	   flags may increase the size of the kernel slightly. )
+	  ( On 32-bit x86, the necessary options added to the compiler
+	    flags may increase the size of the kernel slightly. )
 
 config STATIC_KEYS_SELFTEST
 	bool "Static key selftest"
@@ -98,9 +98,9 @@ config KPROBES_ON_FTRACE
 	depends on KPROBES && HAVE_KPROBES_ON_FTRACE
 	depends on DYNAMIC_FTRACE_WITH_REGS
 	help
-	 If function tracer is enabled and the arch supports full
-	 passing of pt_regs to function tracing, then kprobes can
-	 optimize on top of function tracing.
+	  If function tracer is enabled and the arch supports full
+	  passing of pt_regs to function tracing, then kprobes can
+	  optimize on top of function tracing.
 
 config UPROBES
 	def_bool n
@@ -154,21 +154,21 @@ config HAVE_EFFICIENT_UNALIGNED_ACCESS
 config ARCH_USE_BUILTIN_BSWAP
 	bool
 	help
-	 Modern versions of GCC (since 4.4) have builtin functions
-	 for handling byte-swapping. Using these, instead of the old
-	 inline assembler that the architecture code provides in the
-	 __arch_bswapXX() macros, allows the compiler to see what's
-	 happening and offers more opportunity for optimisation. In
-	 particular, the compiler will be able to combine the byteswap
-	 with a nearby load or store and use load-and-swap or
-	 store-and-swap instructions if the architecture has them. It
-	 should almost *never* result in code which is worse than the
-	 hand-coded assembler in <asm/swab.h>.  But just in case it
-	 does, the use of the builtins is optional.
+	  Modern versions of GCC (since 4.4) have builtin functions
+	  for handling byte-swapping. Using these, instead of the old
+	  inline assembler that the architecture code provides in the
+	  __arch_bswapXX() macros, allows the compiler to see what's
+	  happening and offers more opportunity for optimisation. In
+	  particular, the compiler will be able to combine the byteswap
+	  with a nearby load or store and use load-and-swap or
+	  store-and-swap instructions if the architecture has them. It
+	  should almost *never* result in code which is worse than the
+	  hand-coded assembler in <asm/swab.h>.  But just in case it
+	  does, the use of the builtins is optional.
 
-	 Any architecture with load-and-swap or store-and-swap
-	 instructions should set this. And it shouldn't hurt to set it
-	 on architectures that don't have such instructions.
+	  Any architecture with load-and-swap or store-and-swap
+	  instructions should set this. And it shouldn't hurt to set it
+	  on architectures that don't have such instructions.
 
 config KRETPROBES
 	def_bool y
@@ -720,13 +720,13 @@ config LTO_CLANG_FULL
 	depends on !COMPILE_TEST
 	select LTO_CLANG
 	help
-          This option enables Clang's full Link Time Optimization (LTO), which
-          allows the compiler to optimize the kernel globally. If you enable
-          this option, the compiler generates LLVM bitcode instead of ELF
-          object files, and the actual compilation from bitcode happens at
-          the LTO link step, which may take several minutes depending on the
-          kernel configuration. More information can be found from LLVM's
-          documentation:
+	  This option enables Clang's full Link Time Optimization (LTO), which
+	  allows the compiler to optimize the kernel globally. If you enable
+	  this option, the compiler generates LLVM bitcode instead of ELF
+	  object files, and the actual compilation from bitcode happens at
+	  the LTO link step, which may take several minutes depending on the
+	  kernel configuration. More information can be found from LLVM's
+	  documentation:
 
 	    https://llvm.org/docs/LinkTimeOptimization.html
 
@@ -1330,9 +1330,9 @@ config ARCH_HAS_CC_PLATFORM
 	bool
 
 config HAVE_SPARSE_SYSCALL_NR
-       bool
-       help
-          An architecture should select this if its syscall numbering is sparse
+	bool
+	help
+	  An architecture should select this if its syscall numbering is sparse
 	  to save space. For example, MIPS architecture has a syscall array with
 	  entries at 4000, 5000 and 6000 locations. This option turns on syscall
 	  related optimizations for a given architecture.
@@ -1356,35 +1356,35 @@ config HAVE_PREEMPT_DYNAMIC_CALL
 	depends on HAVE_STATIC_CALL
 	select HAVE_PREEMPT_DYNAMIC
 	help
-	   An architecture should select this if it can handle the preemption
-	   model being selected at boot time using static calls.
+	  An architecture should select this if it can handle the preemption
+	  model being selected at boot time using static calls.
 
-	   Where an architecture selects HAVE_STATIC_CALL_INLINE, any call to a
-	   preemption function will be patched directly.
+	  Where an architecture selects HAVE_STATIC_CALL_INLINE, any call to a
+	  preemption function will be patched directly.
 
-	   Where an architecture does not select HAVE_STATIC_CALL_INLINE, any
-	   call to a preemption function will go through a trampoline, and the
-	   trampoline will be patched.
+	  Where an architecture does not select HAVE_STATIC_CALL_INLINE, any
+	  call to a preemption function will go through a trampoline, and the
+	  trampoline will be patched.
 
-	   It is strongly advised to support inline static call to avoid any
-	   overhead.
+	  It is strongly advised to support inline static call to avoid any
+	  overhead.
 
 config HAVE_PREEMPT_DYNAMIC_KEY
 	bool
 	depends on HAVE_ARCH_JUMP_LABEL
 	select HAVE_PREEMPT_DYNAMIC
 	help
-	   An architecture should select this if it can handle the preemption
-	   model being selected at boot time using static keys.
+	  An architecture should select this if it can handle the preemption
+	  model being selected at boot time using static keys.
 
-	   Each preemption function will be given an early return based on a
-	   static key. This should have slightly lower overhead than non-inline
-	   static calls, as this effectively inlines each trampoline into the
-	   start of its callee. This may avoid redundant work, and may
-	   integrate better with CFI schemes.
+	  Each preemption function will be given an early return based on a
+	  static key. This should have slightly lower overhead than non-inline
+	  static calls, as this effectively inlines each trampoline into the
+	  start of its callee. This may avoid redundant work, and may
+	  integrate better with CFI schemes.
 
-	   This will have greater overhead than using inline static calls as
-	   the call to the preemption function cannot be entirely elided.
+	  This will have greater overhead than using inline static calls as
+	  the call to the preemption function cannot be entirely elided.
 
 config ARCH_WANT_LD_ORPHAN_WARN
 	bool
@@ -1407,8 +1407,8 @@ config ARCH_SUPPORTS_PAGE_TABLE_CHECK
 config ARCH_SPLIT_ARG64
 	bool
 	help
-	   If a 32-bit architecture requires 64-bit arguments to be split into
-	   pairs of 32-bit arguments, select this option.
+	  If a 32-bit architecture requires 64-bit arguments to be split into
+	  pairs of 32-bit arguments, select this option.
 
 config ARCH_HAS_ELFCORE_COMPAT
 	bool

arch/alpha/kernel/process.c

@@ -74,7 +74,7 @@ struct halt_info {
 static void
 common_shutdown_1(void *generic_ptr)
 {
-	struct halt_info *how = (struct halt_info *)generic_ptr;
+	struct halt_info *how = generic_ptr;
 	struct percpu_struct *cpup;
 	unsigned long *pflags, flags;
 	int cpuid = smp_processor_id();

arch/alpha/kernel/smp.c

@@ -628,7 +628,7 @@ flush_tlb_all(void)
 static void
 ipi_flush_tlb_mm(void *x)
 {
-	struct mm_struct *mm = (struct mm_struct *) x;
+	struct mm_struct *mm = x;
 	if (mm == current->active_mm && !asn_locked())
 		flush_tlb_current(mm);
 	else
@@ -670,7 +670,7 @@ struct flush_tlb_page_struct {
 static void
 ipi_flush_tlb_page(void *x)
 {
-	struct flush_tlb_page_struct *data = (struct flush_tlb_page_struct *)x;
+	struct flush_tlb_page_struct *data = x;
 	struct mm_struct * mm = data->mm;
 
 	if (mm == current->active_mm && !asn_locked())