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authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-09 22:34:26 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-09 22:34:26 +0300
commite9a83bd2322035ed9d7dcf35753d3f984d76c6a5 (patch)
tree66dc466ff9aec0f9bb7f39cba50a47eab6585559 /Documentation/fault-injection
parent7011b7e1b702cc76f9e969b41d9a95969f2aecaa (diff)
parent454f96f2b738374da4b0a703b1e2e7aed82c4486 (diff)
downloadlinux-e9a83bd2322035ed9d7dcf35753d3f984d76c6a5.tar.xz
Merge tag 'docs-5.3' of git://git.lwn.net/linux
Pull Documentation updates from Jonathan Corbet: "It's been a relatively busy cycle for docs: - A fair pile of RST conversions, many from Mauro. These create more than the usual number of simple but annoying merge conflicts with other trees, unfortunately. He has a lot more of these waiting on the wings that, I think, will go to you directly later on. - A new document on how to use merges and rebases in kernel repos, and one on Spectre vulnerabilities. - Various improvements to the build system, including automatic markup of function() references because some people, for reasons I will never understand, were of the opinion that :c:func:``function()`` is unattractive and not fun to type. - We now recommend using sphinx 1.7, but still support back to 1.4. - Lots of smaller improvements, warning fixes, typo fixes, etc" * tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits) docs: automarkup.py: ignore exceptions when seeking for xrefs docs: Move binderfs to admin-guide Disable Sphinx SmartyPants in HTML output doc: RCU callback locks need only _bh, not necessarily _irq docs: format kernel-parameters -- as code Doc : doc-guide : Fix a typo platform: x86: get rid of a non-existent document Add the RCU docs to the core-api manual Documentation: RCU: Add TOC tree hooks Documentation: RCU: Rename txt files to rst Documentation: RCU: Convert RCU UP systems to reST Documentation: RCU: Convert RCU linked list to reST Documentation: RCU: Convert RCU basic concepts to reST docs: filesystems: Remove uneeded .rst extension on toctables scripts/sphinx-pre-install: fix out-of-tree build docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/ Documentation: PGP: update for newer HW devices Documentation: Add section about CPU vulnerabilities for Spectre Documentation: platform: Delete x86-laptop-drivers.txt docs: Note that :c:func: should no longer be used ...
Diffstat (limited to 'Documentation/fault-injection')
-rw-r--r--Documentation/fault-injection/fault-injection.rst (renamed from Documentation/fault-injection/fault-injection.txt)281
-rw-r--r--Documentation/fault-injection/index.rst20
-rw-r--r--Documentation/fault-injection/notifier-error-inject.rst (renamed from Documentation/fault-injection/notifier-error-inject.txt)18
-rw-r--r--Documentation/fault-injection/nvme-fault-injection.rst178
-rw-r--r--Documentation/fault-injection/nvme-fault-injection.txt172
-rw-r--r--Documentation/fault-injection/provoke-crashes.rst48
-rw-r--r--Documentation/fault-injection/provoke-crashes.txt38
7 files changed, 403 insertions, 352 deletions
diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.rst
index a17517a083c3..f51bb21d20e4 100644
--- a/Documentation/fault-injection/fault-injection.txt
+++ b/Documentation/fault-injection/fault-injection.rst
@@ -1,3 +1,4 @@
+===========================================
Fault injection capabilities infrastructure
===========================================
@@ -7,36 +8,36 @@ See also drivers/md/md-faulty.c and "every_nth" module option for scsi_debug.
Available fault injection capabilities
--------------------------------------
-o failslab
+- failslab
injects slab allocation failures. (kmalloc(), kmem_cache_alloc(), ...)
-o fail_page_alloc
+- fail_page_alloc
injects page allocation failures. (alloc_pages(), get_free_pages(), ...)
-o fail_futex
+- fail_futex
injects futex deadlock and uaddr fault errors.
-o fail_make_request
+- fail_make_request
injects disk IO errors on devices permitted by setting
/sys/block/<device>/make-it-fail or
/sys/block/<device>/<partition>/make-it-fail. (generic_make_request())
-o fail_mmc_request
+- fail_mmc_request
injects MMC data errors on devices permitted by setting
debugfs entries under /sys/kernel/debug/mmc0/fail_mmc_request
-o fail_function
+- fail_function
injects error return on specific functions, which are marked by
ALLOW_ERROR_INJECTION() macro, by setting debugfs entries
under /sys/kernel/debug/fail_function. No boot option supported.
-o NVMe fault injection
+- NVMe fault injection
inject NVMe status code and retry flag on devices permitted by setting
debugfs entries under /sys/kernel/debug/nvme*/fault_inject. The default
@@ -47,7 +48,8 @@ o NVMe fault injection
Configure fault-injection capabilities behavior
-----------------------------------------------
-o debugfs entries
+debugfs entries
+^^^^^^^^^^^^^^^
fault-inject-debugfs kernel module provides some debugfs entries for runtime
configuration of fault-injection capabilities.
@@ -55,6 +57,7 @@ configuration of fault-injection capabilities.
- /sys/kernel/debug/fail*/probability:
likelihood of failure injection, in percent.
+
Format: <percent>
Note that one-failure-per-hundred is a very high error rate
@@ -83,6 +86,7 @@ configuration of fault-injection capabilities.
- /sys/kernel/debug/fail*/verbose
Format: { 0 | 1 | 2 }
+
specifies the verbosity of the messages when failure is
injected. '0' means no messages; '1' will print only a single
log line per failure; '2' will print a call trace too -- useful
@@ -91,14 +95,15 @@ configuration of fault-injection capabilities.
- /sys/kernel/debug/fail*/task-filter:
Format: { 'Y' | 'N' }
+
A value of 'N' disables filtering by process (default).
Any positive value limits failures to only processes indicated by
/proc/<pid>/make-it-fail==1.
-- /sys/kernel/debug/fail*/require-start:
-- /sys/kernel/debug/fail*/require-end:
-- /sys/kernel/debug/fail*/reject-start:
-- /sys/kernel/debug/fail*/reject-end:
+- /sys/kernel/debug/fail*/require-start,
+ /sys/kernel/debug/fail*/require-end,
+ /sys/kernel/debug/fail*/reject-start,
+ /sys/kernel/debug/fail*/reject-end:
specifies the range of virtual addresses tested during
stacktrace walking. Failure is injected only if some caller
@@ -116,6 +121,7 @@ configuration of fault-injection capabilities.
- /sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:
Format: { 'Y' | 'N' }
+
default is 'N', setting it to 'Y' won't inject failures into
highmem/user allocations.
@@ -123,6 +129,7 @@ configuration of fault-injection capabilities.
- /sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:
Format: { 'Y' | 'N' }
+
default is 'N', setting it to 'Y' will inject failures
only into non-sleep allocations (GFP_ATOMIC allocations).
@@ -134,12 +141,14 @@ configuration of fault-injection capabilities.
- /sys/kernel/debug/fail_futex/ignore-private:
Format: { 'Y' | 'N' }
+
default is 'N', setting it to 'Y' will disable failure injections
when dealing with private (address space) futexes.
- /sys/kernel/debug/fail_function/inject:
Format: { 'function-name' | '!function-name' | '' }
+
specifies the target function of error injection by name.
If the function name leads '!' prefix, given function is
removed from injection list. If nothing specified ('')
@@ -160,10 +169,11 @@ configuration of fault-injection capabilities.
function for given function. This will be created when
user specifies new injection entry.
-o Boot option
+Boot option
+^^^^^^^^^^^
In order to inject faults while debugfs is not available (early boot time),
-use the boot option:
+use the boot option::
failslab=
fail_page_alloc=
@@ -171,10 +181,11 @@ use the boot option:
fail_futex=
mmc_core.fail_request=<interval>,<probability>,<space>,<times>
-o proc entries
+proc entries
+^^^^^^^^^^^^
-- /proc/<pid>/fail-nth:
-- /proc/self/task/<tid>/fail-nth:
+- /proc/<pid>/fail-nth,
+ /proc/self/task/<tid>/fail-nth:
Write to this file of integer N makes N-th call in the task fail.
Read from this file returns a integer value. A value of '0' indicates
@@ -191,16 +202,16 @@ o proc entries
How to add new fault injection capability
-----------------------------------------
-o #include <linux/fault-inject.h>
+- #include <linux/fault-inject.h>
-o define the fault attributes
+- define the fault attributes
DECLARE_FAULT_ATTR(name);
Please see the definition of struct fault_attr in fault-inject.h
for details.
-o provide a way to configure fault attributes
+- provide a way to configure fault attributes
- boot option
@@ -222,126 +233,126 @@ o provide a way to configure fault attributes
single kernel module, it is better to provide module parameters to
configure the fault attributes.
-o add a hook to insert failures
+- add a hook to insert failures
- Upon should_fail() returning true, client code should inject a failure.
+ Upon should_fail() returning true, client code should inject a failure:
should_fail(attr, size);
Application Examples
--------------------
-o Inject slab allocation failures into module init/exit code
+- Inject slab allocation failures into module init/exit code::
-#!/bin/bash
+ #!/bin/bash
-FAILTYPE=failslab
-echo Y > /sys/kernel/debug/$FAILTYPE/task-filter
-echo 10 > /sys/kernel/debug/$FAILTYPE/probability
-echo 100 > /sys/kernel/debug/$FAILTYPE/interval
-echo -1 > /sys/kernel/debug/$FAILTYPE/times
-echo 0 > /sys/kernel/debug/$FAILTYPE/space
-echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
-echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
+ FAILTYPE=failslab
+ echo Y > /sys/kernel/debug/$FAILTYPE/task-filter
+ echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+ echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+ echo -1 > /sys/kernel/debug/$FAILTYPE/times
+ echo 0 > /sys/kernel/debug/$FAILTYPE/space
+ echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+ echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
-faulty_system()
-{
+ faulty_system()
+ {
bash -c "echo 1 > /proc/self/make-it-fail && exec $*"
-}
+ }
-if [ $# -eq 0 ]
-then
+ if [ $# -eq 0 ]
+ then
echo "Usage: $0 modulename [ modulename ... ]"
exit 1
-fi
+ fi
-for m in $*
-do
+ for m in $*
+ do
echo inserting $m...
faulty_system modprobe $m
echo removing $m...
faulty_system modprobe -r $m
-done
+ done
------------------------------------------------------------------------------
-o Inject page allocation failures only for a specific module
+- Inject page allocation failures only for a specific module::
-#!/bin/bash
+ #!/bin/bash
-FAILTYPE=fail_page_alloc
-module=$1
+ FAILTYPE=fail_page_alloc
+ module=$1
-if [ -z $module ]
-then
+ if [ -z $module ]
+ then
echo "Usage: $0 <modulename>"
exit 1
-fi
+ fi
-modprobe $module
+ modprobe $module
-if [ ! -d /sys/module/$module/sections ]
-then
+ if [ ! -d /sys/module/$module/sections ]
+ then
echo Module $module is not loaded
exit 1
-fi
+ fi
-cat /sys/module/$module/sections/.text > /sys/kernel/debug/$FAILTYPE/require-start
-cat /sys/module/$module/sections/.data > /sys/kernel/debug/$FAILTYPE/require-end
+ cat /sys/module/$module/sections/.text > /sys/kernel/debug/$FAILTYPE/require-start
+ cat /sys/module/$module/sections/.data > /sys/kernel/debug/$FAILTYPE/require-end
-echo N > /sys/kernel/debug/$FAILTYPE/task-filter
-echo 10 > /sys/kernel/debug/$FAILTYPE/probability
-echo 100 > /sys/kernel/debug/$FAILTYPE/interval
-echo -1 > /sys/kernel/debug/$FAILTYPE/times
-echo 0 > /sys/kernel/debug/$FAILTYPE/space
-echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
-echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
-echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
-echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth
+ echo N > /sys/kernel/debug/$FAILTYPE/task-filter
+ echo 10 > /sys/kernel/debug/$FAILTYPE/probability
+ echo 100 > /sys/kernel/debug/$FAILTYPE/interval
+ echo -1 > /sys/kernel/debug/$FAILTYPE/times
+ echo 0 > /sys/kernel/debug/$FAILTYPE/space
+ echo 2 > /sys/kernel/debug/$FAILTYPE/verbose
+ echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
+ echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
+ echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth
-trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
+ trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT
-echo "Injecting errors into the module $module... (interrupt to stop)"
-sleep 1000000
+ echo "Injecting errors into the module $module... (interrupt to stop)"
+ sleep 1000000
------------------------------------------------------------------------------
-o Inject open_ctree error while btrfs mount
-
-#!/bin/bash
-
-rm -f testfile.img
-dd if=/dev/zero of=testfile.img bs=1M seek=1000 count=1
-DEVICE=$(losetup --show -f testfile.img)
-mkfs.btrfs -f $DEVICE
-mkdir -p tmpmnt
-
-FAILTYPE=fail_function
-FAILFUNC=open_ctree
-echo $FAILFUNC > /sys/kernel/debug/$FAILTYPE/inject
-echo -12 > /sys/kernel/debug/$FAILTYPE/$FAILFUNC/retval
-echo N > /sys/kernel/debug/$FAILTYPE/task-filter
-echo 100 > /sys/kernel/debug/$FAILTYPE/probability
-echo 0 > /sys/kernel/debug/$FAILTYPE/interval
-echo -1 > /sys/kernel/debug/$FAILTYPE/times
-echo 0 > /sys/kernel/debug/$FAILTYPE/space
-echo 1 > /sys/kernel/debug/$FAILTYPE/verbose
-
-mount -t btrfs $DEVICE tmpmnt
-if [ $? -ne 0 ]
-then
+- Inject open_ctree error while btrfs mount::
+
+ #!/bin/bash
+
+ rm -f testfile.img
+ dd if=/dev/zero of=testfile.img bs=1M seek=1000 count=1
+ DEVICE=$(losetup --show -f testfile.img)
+ mkfs.btrfs -f $DEVICE
+ mkdir -p tmpmnt
+
+ FAILTYPE=fail_function
+ FAILFUNC=open_ctree
+ echo $FAILFUNC > /sys/kernel/debug/$FAILTYPE/inject
+ echo -12 > /sys/kernel/debug/$FAILTYPE/$FAILFUNC/retval
+ echo N > /sys/kernel/debug/$FAILTYPE/task-filter
+ echo 100 > /sys/kernel/debug/$FAILTYPE/probability
+ echo 0 > /sys/kernel/debug/$FAILTYPE/interval
+ echo -1 > /sys/kernel/debug/$FAILTYPE/times
+ echo 0 > /sys/kernel/debug/$FAILTYPE/space
+ echo 1 > /sys/kernel/debug/$FAILTYPE/verbose
+
+ mount -t btrfs $DEVICE tmpmnt
+ if [ $? -ne 0 ]
+ then
echo "SUCCESS!"
-else
+ else
echo "FAILED!"
umount tmpmnt
-fi
+ fi
-echo > /sys/kernel/debug/$FAILTYPE/inject
+ echo > /sys/kernel/debug/$FAILTYPE/inject
-rmdir tmpmnt
-losetup -d $DEVICE
-rm testfile.img
+ rmdir tmpmnt
+ losetup -d $DEVICE
+ rm testfile.img
Tool to run command with failslab or fail_page_alloc
@@ -354,43 +365,43 @@ see the following examples.
Examples:
Run a command "make -C tools/testing/selftests/ run_tests" with injecting slab
-allocation failure.
+allocation failure::
# ./tools/testing/fault-injection/failcmd.sh \
-- make -C tools/testing/selftests/ run_tests
Same as above except to specify 100 times failures at most instead of one time
-at most by default.
+at most by default::
# ./tools/testing/fault-injection/failcmd.sh --times=100 \
-- make -C tools/testing/selftests/ run_tests
Same as above except to inject page allocation failure instead of slab
-allocation failure.
+allocation failure::
# env FAILCMD_TYPE=fail_page_alloc \
./tools/testing/fault-injection/failcmd.sh --times=100 \
- -- make -C tools/testing/selftests/ run_tests
+ -- make -C tools/testing/selftests/ run_tests
Systematic faults using fail-nth
---------------------------------
The following code systematically faults 0-th, 1-st, 2-nd and so on
-capabilities in the socketpair() system call.
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/socket.h>
-#include <sys/syscall.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <string.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <errno.h>
-
-int main()
-{
+capabilities in the socketpair() system call::
+
+ #include <sys/types.h>
+ #include <sys/stat.h>
+ #include <sys/socket.h>
+ #include <sys/syscall.h>
+ #include <fcntl.h>
+ #include <unistd.h>
+ #include <string.h>
+ #include <stdlib.h>
+ #include <stdio.h>
+ #include <errno.h>
+
+ int main()
+ {
int i, err, res, fail_nth, fds[2];
char buf[128];
@@ -413,23 +424,23 @@ int main()
break;
}
return 0;
-}
-
-An example output:
-
-1-th fault Y: res=-1/23
-2-th fault Y: res=-1/23
-3-th fault Y: res=-1/12
-4-th fault Y: res=-1/12
-5-th fault Y: res=-1/23
-6-th fault Y: res=-1/23
-7-th fault Y: res=-1/23
-8-th fault Y: res=-1/12
-9-th fault Y: res=-1/12
-10-th fault Y: res=-1/12
-11-th fault Y: res=-1/12
-12-th fault Y: res=-1/12
-13-th fault Y: res=-1/12
-14-th fault Y: res=-1/12
-15-th fault Y: res=-1/12
-16-th fault N: res=0/12
+ }
+
+An example output::
+
+ 1-th fault Y: res=-1/23
+ 2-th fault Y: res=-1/23
+ 3-th fault Y: res=-1/12
+ 4-th fault Y: res=-1/12
+ 5-th fault Y: res=-1/23
+ 6-th fault Y: res=-1/23
+ 7-th fault Y: res=-1/23
+ 8-th fault Y: res=-1/12
+ 9-th fault Y: res=-1/12
+ 10-th fault Y: res=-1/12
+ 11-th fault Y: res=-1/12
+ 12-th fault Y: res=-1/12
+ 13-th fault Y: res=-1/12
+ 14-th fault Y: res=-1/12
+ 15-th fault Y: res=-1/12
+ 16-th fault N: res=0/12
diff --git a/Documentation/fault-injection/index.rst b/Documentation/fault-injection/index.rst
new file mode 100644
index 000000000000..92b5639ed07a
--- /dev/null
+++ b/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`
diff --git a/Documentation/fault-injection/notifier-error-inject.txt b/Documentation/fault-injection/notifier-error-inject.rst
index e861d761de24..1668b6e48d3a 100644
--- a/Documentation/fault-injection/notifier-error-inject.txt
+++ b/Documentation/fault-injection/notifier-error-inject.rst
@@ -14,7 +14,8 @@ 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:
@@ -22,7 +23,7 @@ Possible PM notifier events to be failed are:
* 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
diff --git a/Documentation/fault-injection/nvme-fault-injection.rst b/Documentation/fault-injection/nvme-fault-injection.rst
new file mode 100644
index 000000000000..cdb2e829228e
--- /dev/null
+++ b/Documentation/fault-injection/nvme-fault-injection.rst
@@ -0,0 +1,178 @@
+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
+
+Example 3: Inject an error into the 10th admin command
+------------------------------------------------------
+
+::
+
+ echo 100 > /sys/kernel/debug/nvme0/fault_inject/probability
+ echo 10 > /sys/kernel/debug/nvme0/fault_inject/space
+ echo 1 > /sys/kernel/debug/nvme0/fault_inject/times
+ nvme reset /dev/nvme0
+
+Expected Result::
+
+ After NVMe controller reset, the reinitialization may or may not succeed.
+ It depends on which admin command is actually forced to fail.
+
+Message from dmesg::
+
+ nvme nvme0: resetting controller
+ FAULT_INJECTION: forcing a failure.
+ name fault_inject, interval 1, probability 100, space 1, times 1
+ CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.2.0-rc2+ #2
+ Hardware name: MSI MS-7A45/B150M MORTAR ARCTIC (MS-7A45), BIOS 1.50 04/25/2017
+ Call Trace:
+ <IRQ>
+ dump_stack+0x63/0x85
+ should_fail+0x14a/0x170
+ nvme_should_fail+0x38/0x80 [nvme_core]
+ nvme_irq+0x129/0x280 [nvme]
+ ? blk_mq_end_request+0xb3/0x120
+ __handle_irq_event_percpu+0x84/0x1a0
+ handle_irq_event_percpu+0x32/0x80
+ handle_irq_event+0x3b/0x60
+ handle_edge_irq+0x7f/0x1a0
+ handle_irq+0x20/0x30
+ do_IRQ+0x4e/0xe0
+ common_interrupt+0xf/0xf
+ </IRQ>
+ RIP: 0010:cpuidle_enter_state+0xc5/0x460
+ Code: ff e8 8f 5f 86 ff 80 7d c7 00 74 17 9c 58 0f 1f 44 00 00 f6 c4 02 0f 85 69 03 00 00 31 ff e8 62 aa 8c ff fb 66 0f 1f 44 00 00 <45> 85 ed 0f 88 37 03 00 00 4c 8b 45 d0 4c 2b 45 b8 48 ba cf f7 53
+ RSP: 0018:ffffffff88c03dd0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdc
+ RAX: ffff9dac25a2ac80 RBX: ffffffff88d53760 RCX: 000000000000001f
+ RDX: 0000000000000000 RSI: 000000002d958403 RDI: 0000000000000000
+ RBP: ffffffff88c03e18 R08: fffffff75e35ffb7 R09: 00000a49a56c0b48
+ R10: ffffffff88c03da0 R11: 0000000000001b0c R12: ffff9dac25a34d00
+ R13: 0000000000000006 R14: 0000000000000006 R15: ffffffff88d53760
+ cpuidle_enter+0x2e/0x40
+ call_cpuidle+0x23/0x40
+ do_idle+0x201/0x280
+ cpu_startup_entry+0x1d/0x20
+ rest_init+0xaa/0xb0
+ arch_call_rest_init+0xe/0x1b
+ start_kernel+0x51c/0x53b
+ x86_64_start_reservations+0x24/0x26
+ x86_64_start_kernel+0x74/0x77
+ secondary_startup_64+0xa4/0xb0
+ nvme nvme0: Could not set queue count (16385)
+ nvme nvme0: IO queues not created
diff --git a/Documentation/fault-injection/nvme-fault-injection.txt b/Documentation/fault-injection/nvme-fault-injection.txt
deleted file mode 100644
index efcb339a3add..000000000000
--- a/Documentation/fault-injection/nvme-fault-injection.txt
+++ /dev/null
@@ -1,172 +0,0 @@
-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
-
-Example 3: Inject an error into the 10th admin command
-------------------------------------------------------
-
-echo 100 > /sys/kernel/debug/nvme0/fault_inject/probability
-echo 10 > /sys/kernel/debug/nvme0/fault_inject/space
-echo 1 > /sys/kernel/debug/nvme0/fault_inject/times
-nvme reset /dev/nvme0
-
-Expected Result:
-
-After NVMe controller reset, the reinitialization may or may not succeed.
-It depends on which admin command is actually forced to fail.
-
-Message from dmesg:
-
-nvme nvme0: resetting controller
-FAULT_INJECTION: forcing a failure.
-name fault_inject, interval 1, probability 100, space 1, times 1
-CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.2.0-rc2+ #2
-Hardware name: MSI MS-7A45/B150M MORTAR ARCTIC (MS-7A45), BIOS 1.50 04/25/2017
-Call Trace:
- <IRQ>
- dump_stack+0x63/0x85
- should_fail+0x14a/0x170
- nvme_should_fail+0x38/0x80 [nvme_core]
- nvme_irq+0x129/0x280 [nvme]
- ? blk_mq_end_request+0xb3/0x120
- __handle_irq_event_percpu+0x84/0x1a0
- handle_irq_event_percpu+0x32/0x80
- handle_irq_event+0x3b/0x60
- handle_edge_irq+0x7f/0x1a0
- handle_irq+0x20/0x30
- do_IRQ+0x4e/0xe0
- common_interrupt+0xf/0xf
- </IRQ>
-RIP: 0010:cpuidle_enter_state+0xc5/0x460
-Code: ff e8 8f 5f 86 ff 80 7d c7 00 74 17 9c 58 0f 1f 44 00 00 f6 c4 02 0f 85 69 03 00 00 31 ff e8 62 aa 8c ff fb 66 0f 1f 44 00 00 <45> 85 ed 0f 88 37 03 00 00 4c 8b 45 d0 4c 2b 45 b8 48 ba cf f7 53
-RSP: 0018:ffffffff88c03dd0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdc
-RAX: ffff9dac25a2ac80 RBX: ffffffff88d53760 RCX: 000000000000001f
-RDX: 0000000000000000 RSI: 000000002d958403 RDI: 0000000000000000
-RBP: ffffffff88c03e18 R08: fffffff75e35ffb7 R09: 00000a49a56c0b48
-R10: ffffffff88c03da0 R11: 0000000000001b0c R12: ffff9dac25a34d00
-R13: 0000000000000006 R14: 0000000000000006 R15: ffffffff88d53760
- cpuidle_enter+0x2e/0x40
- call_cpuidle+0x23/0x40
- do_idle+0x201/0x280
- cpu_startup_entry+0x1d/0x20
- rest_init+0xaa/0xb0
- arch_call_rest_init+0xe/0x1b
- start_kernel+0x51c/0x53b
- x86_64_start_reservations+0x24/0x26
- x86_64_start_kernel+0x74/0x77
- secondary_startup_64+0xa4/0xb0
-nvme nvme0: Could not set queue count (16385)
-nvme nvme0: IO queues not created
diff --git a/Documentation/fault-injection/provoke-crashes.rst b/Documentation/fault-injection/provoke-crashes.rst
new file mode 100644
index 000000000000..9279a3e12278
--- /dev/null
+++ b/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.
diff --git a/Documentation/fault-injection/provoke-crashes.txt b/Documentation/fault-injection/provoke-crashes.txt
deleted file mode 100644
index 7a9d3d81525b..000000000000
--- a/Documentation/fault-injection/provoke-crashes.txt
+++ /dev/null
@@ -1,38 +0,0 @@
-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.