docs: fault-injection: convert docs to ReST and rename to *.rst

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Federico Vaga <federico.vaga@vaga.pv.it>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/fault-injection/index.rst

@@ -0,0 +1,20 @@
+:orphan:
+
+===============
+fault-injection
+===============
+
+.. toctree::
+    :maxdepth: 1
+
+    fault-injection
+    notifier-error-inject
+    nvme-fault-injection
+    provoke-crashes
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`

Documentation/fault-injection/notifier-error-inject.txt → Documentation/fault-injection/notifier-error-inject.rst

@@ -14,15 +14,16 @@ modules that can be used to test the following notifiers.
 PM notifier error injection module
 ----------------------------------
 This feature is controlled through debugfs interface
-/sys/kernel/debug/notifier-error-inject/pm/actions/<notifier event>/error
+
+  /sys/kernel/debug/notifier-error-inject/pm/actions/<notifier event>/error
 
 Possible PM notifier events to be failed are:
 
  * PM_HIBERNATION_PREPARE
  * PM_SUSPEND_PREPARE
  * PM_RESTORE_PREPARE
 
-Example: Inject PM suspend error (-12 = -ENOMEM)
+Example: Inject PM suspend error (-12 = -ENOMEM)::
 
 	# cd /sys/kernel/debug/notifier-error-inject/pm/
 	# echo -12 > actions/PM_SUSPEND_PREPARE/error
@@ -32,14 +33,15 @@ Example: Inject PM suspend error (-12 = -ENOMEM)
 Memory hotplug notifier error injection module
 ----------------------------------------------
 This feature is controlled through debugfs interface
-/sys/kernel/debug/notifier-error-inject/memory/actions/<notifier event>/error
+
+  /sys/kernel/debug/notifier-error-inject/memory/actions/<notifier event>/error
 
 Possible memory notifier events to be failed are:
 
  * MEM_GOING_ONLINE
  * MEM_GOING_OFFLINE
 
-Example: Inject memory hotplug offline error (-12 == -ENOMEM)
+Example: Inject memory hotplug offline error (-12 == -ENOMEM)::
 
 	# cd /sys/kernel/debug/notifier-error-inject/memory
 	# echo -12 > actions/MEM_GOING_OFFLINE/error
@@ -49,7 +51,8 @@ Example: Inject memory hotplug offline error (-12 == -ENOMEM)
 powerpc pSeries reconfig notifier error injection module
 --------------------------------------------------------
 This feature is controlled through debugfs interface
-/sys/kernel/debug/notifier-error-inject/pSeries-reconfig/actions/<notifier event>/error
+
+  /sys/kernel/debug/notifier-error-inject/pSeries-reconfig/actions/<notifier event>/error
 
 Possible pSeries reconfig notifier events to be failed are:
 
@@ -61,7 +64,8 @@ Possible pSeries reconfig notifier events to be failed are:
 Netdevice notifier error injection module
 ----------------------------------------------
 This feature is controlled through debugfs interface
-/sys/kernel/debug/notifier-error-inject/netdev/actions/<notifier event>/error
+
+  /sys/kernel/debug/notifier-error-inject/netdev/actions/<notifier event>/error
 
 Netdevice notifier events which can be failed are:
 
@@ -75,7 +79,7 @@ Netdevice notifier events which can be failed are:
  * NETDEV_PRECHANGEUPPER
  * NETDEV_CHANGEUPPER
 
-Example: Inject netdevice mtu change error (-22 == -EINVAL)
+Example: Inject netdevice mtu change error (-22 == -EINVAL)::
 
 	# cd /sys/kernel/debug/notifier-error-inject/netdev
 	# echo -22 > actions/NETDEV_CHANGEMTU/error

Documentation/fault-injection/nvme-fault-injection.rst

@@ -0,0 +1,120 @@
+NVMe Fault Injection
+====================
+Linux's fault injection framework provides a systematic way to support
+error injection via debugfs in the /sys/kernel/debug directory. When
+enabled, the default NVME_SC_INVALID_OPCODE with no retry will be
+injected into the nvme_end_request. Users can change the default status
+code and no retry flag via the debugfs. The list of Generic Command
+Status can be found in include/linux/nvme.h
+
+Following examples show how to inject an error into the nvme.
+
+First, enable CONFIG_FAULT_INJECTION_DEBUG_FS kernel config,
+recompile the kernel. After booting up the kernel, do the
+following.
+
+Example 1: Inject default status code with no retry
+---------------------------------------------------
+
+::
+
+  mount /dev/nvme0n1 /mnt
+  echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/times
+  echo 100 > /sys/kernel/debug/nvme0n1/fault_inject/probability
+  cp a.file /mnt
+
+Expected Result::
+
+  cp: cannot stat ‘/mnt/a.file’: Input/output error
+
+Message from dmesg::
+
+  FAULT_INJECTION: forcing a failure.
+  name fault_inject, interval 1, probability 100, space 0, times 1
+  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc8+ #2
+  Hardware name: innotek GmbH VirtualBox/VirtualBox,
+  BIOS VirtualBox 12/01/2006
+  Call Trace:
+    <IRQ>
+    dump_stack+0x5c/0x7d
+    should_fail+0x148/0x170
+    nvme_should_fail+0x2f/0x50 [nvme_core]
+    nvme_process_cq+0xe7/0x1d0 [nvme]
+    nvme_irq+0x1e/0x40 [nvme]
+    __handle_irq_event_percpu+0x3a/0x190
+    handle_irq_event_percpu+0x30/0x70
+    handle_irq_event+0x36/0x60
+    handle_fasteoi_irq+0x78/0x120
+    handle_irq+0xa7/0x130
+    ? tick_irq_enter+0xa8/0xc0
+    do_IRQ+0x43/0xc0
+    common_interrupt+0xa2/0xa2
+    </IRQ>
+  RIP: 0010:native_safe_halt+0x2/0x10
+  RSP: 0018:ffffffff82003e90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd
+  RAX: ffffffff817a10c0 RBX: ffffffff82012480 RCX: 0000000000000000
+  RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
+  RBP: 0000000000000000 R08: 000000008e38ce64 R09: 0000000000000000
+  R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff82012480
+  R13: ffffffff82012480 R14: 0000000000000000 R15: 0000000000000000
+    ? __sched_text_end+0x4/0x4
+    default_idle+0x18/0xf0
+    do_idle+0x150/0x1d0
+    cpu_startup_entry+0x6f/0x80
+    start_kernel+0x4c4/0x4e4
+    ? set_init_arg+0x55/0x55
+    secondary_startup_64+0xa5/0xb0
+    print_req_error: I/O error, dev nvme0n1, sector 9240
+  EXT4-fs error (device nvme0n1): ext4_find_entry:1436:
+  inode #2: comm cp: reading directory lblock 0
+
+Example 2: Inject default status code with retry
+------------------------------------------------
+
+::
+
+  mount /dev/nvme0n1 /mnt
+  echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/times
+  echo 100 > /sys/kernel/debug/nvme0n1/fault_inject/probability
+  echo 1 > /sys/kernel/debug/nvme0n1/fault_inject/status
+  echo 0 > /sys/kernel/debug/nvme0n1/fault_inject/dont_retry
+
+  cp a.file /mnt
+
+Expected Result::
+
+  command success without error
+
+Message from dmesg::
+
+  FAULT_INJECTION: forcing a failure.
+  name fault_inject, interval 1, probability 100, space 0, times 1
+  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.15.0-rc8+ #4
+  Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
+  Call Trace:
+    <IRQ>
+    dump_stack+0x5c/0x7d
+    should_fail+0x148/0x170
+    nvme_should_fail+0x30/0x60 [nvme_core]
+    nvme_loop_queue_response+0x84/0x110 [nvme_loop]
+    nvmet_req_complete+0x11/0x40 [nvmet]
+    nvmet_bio_done+0x28/0x40 [nvmet]
+    blk_update_request+0xb0/0x310
+    blk_mq_end_request+0x18/0x60
+    flush_smp_call_function_queue+0x3d/0xf0
+    smp_call_function_single_interrupt+0x2c/0xc0
+    call_function_single_interrupt+0xa2/0xb0
+    </IRQ>
+  RIP: 0010:native_safe_halt+0x2/0x10
+  RSP: 0018:ffffc9000068bec0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff04
+  RAX: ffffffff817a10c0 RBX: ffff88011a3c9680 RCX: 0000000000000000
+  RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
+  RBP: 0000000000000001 R08: 000000008e38c131 R09: 0000000000000000
+  R10: 0000000000000000 R11: 0000000000000000 R12: ffff88011a3c9680
+  R13: ffff88011a3c9680 R14: 0000000000000000 R15: 0000000000000000
+    ? __sched_text_end+0x4/0x4
+    default_idle+0x18/0xf0
+    do_idle+0x150/0x1d0
+    cpu_startup_entry+0x6f/0x80
+    start_secondary+0x187/0x1e0
+    secondary_startup_64+0xa5/0xb0

Documentation/fault-injection/provoke-crashes.rst

@@ -0,0 +1,48 @@
+===============
+Provoke crashes
+===============
+
+The lkdtm module provides an interface to crash or injure the kernel at
+predefined crashpoints to evaluate the reliability of crash dumps obtained
+using different dumping solutions. The module uses KPROBEs to instrument
+crashing points, but can also crash the kernel directly without KRPOBE
+support.
+
+
+You can provide the way either through module arguments when inserting
+the module, or through a debugfs interface.
+
+Usage::
+
+	insmod lkdtm.ko [recur_count={>0}] cpoint_name=<> cpoint_type=<>
+			[cpoint_count={>0}]
+
+recur_count
+	Recursion level for the stack overflow test. Default is 10.
+
+cpoint_name
+	Crash point where the kernel is to be crashed. It can be
+	one of INT_HARDWARE_ENTRY, INT_HW_IRQ_EN, INT_TASKLET_ENTRY,
+	FS_DEVRW, MEM_SWAPOUT, TIMERADD, SCSI_DISPATCH_CMD,
+	IDE_CORE_CP, DIRECT
+
+cpoint_type
+	Indicates the action to be taken on hitting the crash point.
+	It can be one of PANIC, BUG, EXCEPTION, LOOP, OVERFLOW,
+	CORRUPT_STACK, UNALIGNED_LOAD_STORE_WRITE, OVERWRITE_ALLOCATION,
+	WRITE_AFTER_FREE,
+
+cpoint_count
+	Indicates the number of times the crash point is to be hit
+	to trigger an action. The default is 10.
+
+You can also induce failures by mounting debugfs and writing the type to
+<mountpoint>/provoke-crash/<crashpoint>. E.g.::
+
+  mount -t debugfs debugfs /mnt
+  echo EXCEPTION > /mnt/provoke-crash/INT_HARDWARE_ENTRY
+
+
+A special file is `DIRECT` which will induce the crash directly without
+KPROBE instrumentation. This mode is the only one available when the module
+is built on a kernel without KPROBEs support.