04 Dec, 2015
1 commit
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Since CHANGEUPPER can now fail, add support for it in the newly
introduced netdev notifier error injection infrastructure.Signed-off-by: Ido Schimmel
Signed-off-by: Jiri Pirko
Acked-by: Nikolay Aleksandrov
Signed-off-by: David S. Miller
02 Dec, 2015
1 commit
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This module allows to insert errors in some of netdevice's notifier
events. All network drivers use these notifiers to signal various events
and to check if they are allowed, e.g. PRECHANGEMTU and CHANGEMTU
afterwards. Until recently I had to run failure tests by injecting
a custom module, but now this infrastructure makes it trivial to test
these failure paths. Some of the recent bugs I fixed were found using
this module.
Here's an example:
$ cd /sys/kernel/debug/notifier-error-inject/netdev
$ echo -22 > actions/NETDEV_CHANGEMTU/error
$ ip link set eth0 mtu 1024
RTNETLINK answers: Invalid argumentCC: Akinobu Mita
CC: "David S. Miller"
CC: netdev
Signed-off-by: Nikolay Aleksandrov
Signed-off-by: David S. Miller
20 Jul, 2015
1 commit
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Although futexes are well known for being a royal pita,
we really have very little debugging capabilities - except
for relying on tglx's eye half the time.By simply making use of the existing fault-injection machinery,
we can improve this situation, allowing generating artificial
uaddress faults and deadlock scenarios. Of course, when this is
disabled in production systems, the overhead for failure checks
is practically zero -- so this is very cheap at the same time.
Future work would be nice to now enhance trinity to make use of
this.There is a special tunable 'ignore-private', which can filter
out private futexes. Given the tsk->make_it_fail filter and
this option, pi futexes can be narrowed down pretty closely.Signed-off-by: Davidlohr Bueso
Cc: Peter Zijlstra
Cc: Darren Hart
Cc: Davidlohr Bueso
Link: http://lkml.kernel.org/r/1435645562-975-3-git-send-email-dave@stgolabs.net
Signed-off-by: Thomas Gleixner
19 Nov, 2012
1 commit
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Correct spelling typo in Documentations
Signed-off-by: Jiri Kosina
31 Jul, 2012
2 commits
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This adds tools/testing/fault-injection/failcmd.sh to run a command while
injecting slab/page allocation failures via fault injection.Example:
Run a command "make -C tools/testing/selftests/ run_tests" with
injecting slab allocation failure.# ./tools/testing/fault-injection/failcmd.sh \
-- make -C tools/testing/selftests/ run_testsSame as above except to specify 100 times failures at most instead of
one time at most by default.# ./tools/testing/fault-injection/failcmd.sh --times=100 \
-- make -C tools/testing/selftests/ run_testsSame as above except to inject page allocation failure instead of slab
allocation failure.# env FAILCMD_TYPE=fail_page_alloc \
./tools/testing/fault-injection/failcmd.sh --times=100 \
-- make -C tools/testing/selftests/ run_testsSigned-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patchset provides kernel modules that can be used to test the error
handling of notifier call chain failures by injecting artifical errors to
the following notifier chain callbacks.* CPU notifier
* PM notifier
* memory hotplug notifier
* powerpc pSeries reconfig notifierExample: Inject CPU offline error (-1 == -EPERM)
# cd /sys/kernel/debug/notifier-error-inject/cpu
# echo -1 > actions/CPU_DOWN_PREPARE/error
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permittedThe patchset also adds cpu and memory hotplug tests to
tools/testing/selftests These tests first do simple online and offline
test and then do fault injection tests if notifier error injection
module is available.This patch:
The notifier error injection provides the ability to inject artifical
errors to specified notifier chain callbacks. It is useful to test the
error handling of notifier call chain failures.This adds common basic functions to define which type of events can be
fail and to initialize the debugfs interface to control what error code
should be returned and which event should be failed.Signed-off-by: Akinobu Mita
Cc: Pavel Machek
Cc: "Rafael J. Wysocki"
Cc: Greg KH
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: Dave Jones
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Oct, 2011
2 commits
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Signed-off-by: Per Forlin
Reviewed-by: Akinobu Mita
Signed-off-by: Chris Ball -
Add description on how to enable random fault injection
for MMC IO.Signed-off-by: Per Forlin
Acked-by: Akinobu Mita
Reviewed-by: Linus Walleij
Signed-off-by: Chris Ball
04 Aug, 2011
1 commit
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init_fault_attr_dentries() is used to export fault_attr via debugfs.
But it can only export it in debugfs root directory.Per Forlin is working on mmc_fail_request which adds support to inject
data errors after a completed host transfer in MMC subsystem.The fault_attr for mmc_fail_request should be defined per mmc host and
export it in debugfs directory per mmc host like
/sys/kernel/debug/mmc0/mmc_fail_request.init_fault_attr_dentries() doesn't help for mmc_fail_request. So this
introduces fault_create_debugfs_attr() which is able to create a
directory in the arbitrary directory and replace
init_fault_attr_dentries().[akpm@linux-foundation.org: extraneous semicolon, per Randy]
Signed-off-by: Akinobu Mita
Tested-by: Per Forlin
Cc: Jens Axboe
Cc: Christoph Lameter
Cc: Pekka Enberg
Cc: Matt Mackall
Cc: Randy Dunlap
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Mar, 2010
1 commit
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Add adds a debugfs interface and additional failure modes to LKDTM to
provide similar functionality to the provoke-crash driver submitted here:http://lwn.net/Articles/371208/
Crashes can now be induced either through module parameters (as before)
or through the debugfs interface as in provoke-crash.The patch also provides a new "direct" interface, where KPROBES are not
used, i.e., the crash is invoked directly upon write to the debugfs
file. When built without KPROBES configured, only this mode is available.Signed-off-by: Simon Kagstrom
Cc: M. Mohan Kumar
Cc: Americo Wang
Cc: David Woodhouse
Cc: Ingo Molnar
Cc: "Eric W. Biederman" ,
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Feb, 2010
1 commit
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init_fault_attr_entries() should be init_fault_attr_dentries().
cleanup_fault_attr_entries() should be cleanup_fault_attr_dentries().
Signed-off-by: Anton Blanchard
Acked-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
16 Jun, 2009
1 commit
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Many developers use "/debug/" or "/debugfs/" or "/sys/kernel/debug/"
directory name to mount debugfs filesystem for ftrace according to
./Documentation/tracers/ftrace.txt file.And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
existed in kernel source like ftrace, DRM, Wireless, Documentation,
Network[sky2]files to mount debugfs filesystem.debugfs means debug filesystem for debugging easy to use by greg kroah
hartman. "/sys/kernel/debug/" name is suitable as directory name
of debugfs filesystem.
- debugfs related reference: http://lwn.net/Articles/334546/Fix inconsistency of directory name to mount debugfs filesystem.
* From Steven Rostedt
- find_debugfs() and tracing_files() in this patch.Signed-off-by: GeunSik Lim
Acked-by : Inaky Perez-Gonzalez
Reviewed-by : Steven Rostedt
Reviewed-by : James Smart
CC: Jiri Kosina
CC: David Airlie
CC: Peter Osterlund
CC: Ananth N Mavinakayanahalli
CC: Anil S Keshavamurthy
CC: Masami Hiramatsu
Signed-off-by: Greg Kroah-Hartman
17 Jul, 2007
2 commits
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Fix and cleanup example scripts in fault injection documentation.
1. Eliminate broken oops() shell function.
2. Fold failcmd.sh and failmodule.sh into example scripts. It makes
the example scripts work independent of current working directory.3. Set "space" parameter to 0 to start injecting errors immediately.
4. Use /sys/module//sections/.data as upper bound of
.text section. Because some module doesn't have .exit.text section.Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Limiting smaller allocation failures by fault injection helps to find real
possible bugs. Because higher order allocations are likely to fail and
zero-order allocations are not likely to fail.This patch adds min-order parameter to fail_page_alloc. It specifies the
minimum page allocation order to be injected failures.Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Dec, 2006
4 commits
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Correct, disambiguate, and reformat documentation.
Signed-off-by: Don Mullis
Cc: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch provides stacktrace filtering feature.
The stacktrace filter allows failing only for the caller you are
interested in.For example someone may want to inject kmalloc() failures into
only e100 module. they want to inject not only direct kmalloc() call,
but also indirect allocation, too.- e100_poll --> netif_receive_skb --> packet_rcv_spkt --> skb_clone
--> kmem_cache_allocThis patch enables to detect function calls like this by stacktrace
and inject failures. The script Documentaion/fault-injection/failmodule.sh
helps it.The range of text section of loaded e100 is expected to be
[/sys/module/e100/sections/.text, /sys/module/e100/sections/.exit.text)So failmodule.sh stores these values into /debug/failslab/address-start
and /debug/failslab/address-end. The maximum stacktrace depth is specified
by /debug/failslab/stacktrace-depth.Please see the example that demonstrates how to inject slab allocation
failures only for a specific module
in Documentation/fault-injection/fault-injection.txt[dwm@meer.net: reject failure if any caller lies within specified range]
Signed-off-by: Akinobu Mita
Signed-off-by: Don Mullis
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch provides fault-injection capability for kmalloc.
Boot option:
failslab=,,,
-- specifies the interval of failures.
-- specifies how often it should fail in percent.
-- specifies the size of free space where memory can be
allocated safely in bytes.-- specifies how many times failures may happen at most.
Debugfs:
/debug/failslab/interval
/debug/failslab/probability
/debug/failslab/specifies
/debug/failslab/times
/debug/failslab/ignore-gfp-highmem
/debug/failslab/ignore-gfp-waitExample:
failslab=10,100,0,-1
slab allocation (kmalloc(), kmem_cache_alloc(),..) fails once per 10 times.
Cc: Pekka Enberg
Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch set provides some fault-injection capabilities.
- kmalloc() failures
- alloc_pages() failures
- disk IO errors
We can see what really happens if those failures happen.
In order to enable these fault-injection capabilities:
1. Enable relevant config options (CONFIG_FAILSLAB, CONFIG_PAGE_ALLOC,
CONFIG_MAKE_REQUEST) and if you want to configure them via debugfs,
enable CONFIG_FAULT_INJECTION_DEBUG_FS.2. Build and boot with this kernel
3. Configure fault-injection capabilities behavior by boot option or debugfs
- Boot option
failslab=
fail_page_alloc=
fail_make_request=- Debugfs
/debug/failslab/*
/debug/fail_page_alloc/*
/debug/fail_make_request/*Please refer to the Documentation/fault-injection/fault-injection.txt
for details.4. See what really happens.
Signed-off-by: Akinobu Mita
Signed-off-by: Don Mullis
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
