€•       Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ3/translations/zh_CN/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/zh_TW/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/it_IT/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/ja_JP/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/ko_KR/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒPortuguese (Brazilian)”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/pt_BR/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh–sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ3/translations/sp_SP/fault-injection/fault-injection”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒ+Fault injection capabilities infrastructure”h]”hŒ+Fault injection capabilities infrastructure”…””}”(hh¼h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhh·h²hh³ŒM/var/lib/git/docbuild/linux/Documentation/fault-injection/fault-injection.rst”h´KubhŒ	paragraph”“”)”}”(hŒ2See also "every_nth" module option for scsi_debug.”h]”hŒ6See also â€œevery_nthâ€ module option for scsi_debug.”…””}”(hhÍh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khh·h²hubh¶)”}”(hhh]”(h»)”}”(hŒ&Available fault injection capabilities”h]”hŒ&Available fault injection capabilities”…””}”(hhÞh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhhÛh²hh³hÊh´K	ubhŒbullet_list”“”)”}”(hhh]”(hŒ	list_item”“”)”}”(hŒQfailslab

injects slab allocation failures. (kmalloc(), kmem_cache_alloc(), ...)
”h]”(hÌ)”}”(hŒfailslab”h]”hŒfailslab”…””}”(hh÷h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KhhóubhÌ)”}”(hŒFinjects slab allocation failures. (kmalloc(), kmem_cache_alloc(), ...)”h]”hŒFinjects slab allocation failures. (kmalloc(), kmem_cache_alloc(), ...)”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khhóubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒZfail_page_alloc

injects page allocation failures. (alloc_pages(), get_free_pages(), ...)
”h]”(hÌ)”}”(hŒfail_page_alloc”h]”hŒfail_page_alloc”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj  ubhÌ)”}”(hŒHinjects page allocation failures. (alloc_pages(), get_free_pages(), ...)”h]”hŒHinjects page allocation failures. (alloc_pages(), get_free_pages(), ...)”…””}”(hj+  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒefail_usercopy

injects failures in user memory access functions. (copy_from_user(), get_user(), ...)
”h]”(hÌ)”}”(hŒfail_usercopy”h]”hŒfail_usercopy”…””}”(hjC  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj?  ubhÌ)”}”(hŒUinjects failures in user memory access functions. (copy_from_user(), get_user(), ...)”h]”hŒUinjects failures in user memory access functions. (copy_from_user(), get_user(), ...)”…””}”(hjQ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj?  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒ;fail_futex

injects futex deadlock and uaddr fault errors.
”h]”(hÌ)”}”(hŒ
fail_futex”h]”hŒ
fail_futex”…””}”(hji  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khje  ubhÌ)”}”(hŒ.injects futex deadlock and uaddr fault errors.”h]”hŒ.injects futex deadlock and uaddr fault errors.”…””}”(hjw  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khje  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒ<fail_sunrpc

injects kernel RPC client and server failures.
”h]”(hÌ)”}”(hŒfail_sunrpc”h]”hŒfail_sunrpc”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj‹  ubhÌ)”}”(hŒ.injects kernel RPC client and server failures.”h]”hŒ.injects kernel RPC client and server failures.”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj‹  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒ²fail_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. (submit_bio_noacct())
”h]”(hÌ)”}”(hŒfail_make_request”h]”hŒfail_make_request”…””}”(hjµ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj±  ubhÌ)”}”(hŒžinjects disk IO errors on devices permitted by setting
/sys/block/<device>/make-it-fail or
/sys/block/<device>/<partition>/make-it-fail. (submit_bio_noacct())”h]”hŒžinjects disk IO errors on devices permitted by setting
/sys/block/<device>/make-it-fail or
/sys/block/<device>/<partition>/make-it-fail. (submit_bio_noacct())”…””}”(hjÃ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K!hj±  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒˆfail_mmc_request

injects MMC data errors on devices permitted by setting
debugfs entries under /sys/kernel/debug/mmc0/fail_mmc_request
”h]”(hÌ)”}”(hŒfail_mmc_request”h]”hŒfail_mmc_request”…””}”(hjÛ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K%hj×  ubhÌ)”}”(hŒuinjects MMC data errors on devices permitted by setting
debugfs entries under /sys/kernel/debug/mmc0/fail_mmc_request”h]”hŒuinjects MMC data errors on devices permitted by setting
debugfs entries under /sys/kernel/debug/mmc0/fail_mmc_request”…””}”(hjé  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K'hj×  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hŒÊfail_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.
”h]”(hÌ)”}”(hŒfail_function”h]”hŒfail_function”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K*hjý  ubhÌ)”}”(hŒºinjects error return on specific functions, which are marked by
ALLOW_ERROR_INJECTION() macro, by setting debugfs entries
under /sys/kernel/debug/fail_function. No boot option supported.”h]”hŒºinjects error return on specific functions, which are marked by
ALLOW_ERROR_INJECTION() macro, by setting debugfs entries
under /sys/kernel/debug/fail_function. No boot option supported.”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K,hjý  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hX‡  fail_skb_realloc

inject skb (socket buffer) reallocation events into the network path. The
primary goal is to identify and prevent issues related to pointer
mismanagement in the network subsystem.  By forcing skb reallocation at
strategic points, this feature creates scenarios where existing pointers to
skb headers become invalid.

When the fault is injected and the reallocation is triggered, cached pointers
to skb headers and data no longer reference valid memory locations. This
deliberate invalidation helps expose code paths where proper pointer updating
is neglected after a reallocation event.

By creating these controlled fault scenarios, the system can catch instances
where stale pointers are used, potentially leading to memory corruption or
system instability.

To select the interface to act on, write the network name to
/sys/kernel/debug/fail_skb_realloc/devname.
If this field is left empty (which is the default value), skb reallocation
will be forced on all network interfaces.

The effectiveness of this fault detection is enhanced when KASAN is
enabled, as it helps identify invalid memory references and use-after-free
(UAF) issues.
”h]”(hÌ)”}”(hŒfail_skb_realloc”h]”hŒfail_skb_realloc”…””}”(hj'  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K0hj#  ubhÌ)”}”(hX;  inject skb (socket buffer) reallocation events into the network path. The
primary goal is to identify and prevent issues related to pointer
mismanagement in the network subsystem.  By forcing skb reallocation at
strategic points, this feature creates scenarios where existing pointers to
skb headers become invalid.”h]”hX;  inject skb (socket buffer) reallocation events into the network path. The
primary goal is to identify and prevent issues related to pointer
mismanagement in the network subsystem.  By forcing skb reallocation at
strategic points, this feature creates scenarios where existing pointers to
skb headers become invalid.”…””}”(hj5  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K2hj#  ubhÌ)”}”(hX  When the fault is injected and the reallocation is triggered, cached pointers
to skb headers and data no longer reference valid memory locations. This
deliberate invalidation helps expose code paths where proper pointer updating
is neglected after a reallocation event.”h]”hX  When the fault is injected and the reallocation is triggered, cached pointers
to skb headers and data no longer reference valid memory locations. This
deliberate invalidation helps expose code paths where proper pointer updating
is neglected after a reallocation event.”…””}”(hjC  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K8hj#  ubhÌ)”}”(hŒ«By creating these controlled fault scenarios, the system can catch instances
where stale pointers are used, potentially leading to memory corruption or
system instability.”h]”hŒ«By creating these controlled fault scenarios, the system can catch instances
where stale pointers are used, potentially leading to memory corruption or
system instability.”…””}”(hjQ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K=hj#  ubhÌ)”}”(hŒÝTo select the interface to act on, write the network name to
/sys/kernel/debug/fail_skb_realloc/devname.
If this field is left empty (which is the default value), skb reallocation
will be forced on all network interfaces.”h]”hŒÝTo select the interface to act on, write the network name to
/sys/kernel/debug/fail_skb_realloc/devname.
If this field is left empty (which is the default value), skb reallocation
will be forced on all network interfaces.”…””}”(hj_  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KAhj#  ubhÌ)”}”(hŒœThe effectiveness of this fault detection is enhanced when KASAN is
enabled, as it helps identify invalid memory references and use-after-free
(UAF) issues.”h]”hŒœThe effectiveness of this fault detection is enhanced when KASAN is
enabled, as it helps identify invalid memory references and use-after-free
(UAF) issues.”…””}”(hjm  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KFhj#  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hX  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
status code is NVME_SC_INVALID_OPCODE with no retry. The status code and
retry flag can be set via the debugfs.
”h]”(hÌ)”}”(hŒNVMe fault injection”h]”hŒNVMe fault injection”…””}”(hj…  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KJhj  ubhÌ)”}”(hŒþinject NVMe status code and retry flag on devices permitted by setting
debugfs entries under /sys/kernel/debug/nvme*/fault_inject. The default
status code is NVME_SC_INVALID_OPCODE with no retry. The status code and
retry flag can be set via the debugfs.”h]”hŒþinject NVMe status code and retry flag on devices permitted by setting
debugfs entries under /sys/kernel/debug/nvme*/fault_inject. The default
status code is NVME_SC_INVALID_OPCODE with no retry. The status code and
retry flag can be set via the debugfs.”…””}”(hj“  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KLhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubhò)”}”(hXc  Null test block driver fault injection

inject IO timeouts by setting config items under
/sys/kernel/config/nullb/<disk>/timeout_inject,
inject requeue requests by setting config items under
/sys/kernel/config/nullb/<disk>/requeue_inject, and
inject init_hctx() errors by setting config items under
/sys/kernel/config/nullb/<disk>/init_hctx_fault_inject.
”h]”(hÌ)”}”(hŒ&Null test block driver fault injection”h]”hŒ&Null test block driver fault injection”…””}”(hj«  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KQhj§  ubhÌ)”}”(hX:  inject IO timeouts by setting config items under
/sys/kernel/config/nullb/<disk>/timeout_inject,
inject requeue requests by setting config items under
/sys/kernel/config/nullb/<disk>/requeue_inject, and
inject init_hctx() errors by setting config items under
/sys/kernel/config/nullb/<disk>/init_hctx_fault_inject.”h]”hX:  inject IO timeouts by setting config items under
/sys/kernel/config/nullb/<disk>/timeout_inject,
inject requeue requests by setting config items under
/sys/kernel/config/nullb/<disk>/requeue_inject, and
inject init_hctx() errors by setting config items under
/sys/kernel/config/nullb/<disk>/init_hctx_fault_inject.”…””}”(hj¹  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KShj§  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhhîh²hh³hÊh´Nubeh}”(h]”h ]”h"]”h$]”h&]”Œbullet”Œ-”uh1hìh³hÊh´KhhÛh²hubeh}”(h]”Œ&available-fault-injection-capabilities”ah ]”h"]”Œ&available fault injection capabilities”ah$]”h&]”uh1hµhh·h²hh³hÊh´K	ubh¶)”}”(hhh]”(h»)”}”(hŒ/Configure fault-injection capabilities behavior”h]”hŒ/Configure fault-injection capabilities behavior”…””}”(hjà  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhjÝ  h²hh³hÊh´K[ubh¶)”}”(hhh]”(h»)”}”(hŒdebugfs entries”h]”hŒdebugfs entries”…””}”(hjñ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhjî  h²hh³hÊh´K^ubhÌ)”}”(hŒ{fault-inject-debugfs kernel module provides some debugfs entries for runtime
configuration of fault-injection capabilities.”h]”hŒ{fault-inject-debugfs kernel module provides some debugfs entries for runtime
configuration of fault-injection capabilities.”…””}”(hjÿ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K`hjî  h²hubhí)”}”(hhh]”(hò)”}”(hX:  /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
      for some testcases.  Consider setting probability=100 and configure
      /sys/kernel/debug/fail*/interval for such testcases.
”h]”(hÌ)”}”(hŒ$/sys/kernel/debug/fail*/probability:”h]”hŒ$/sys/kernel/debug/fail*/probability:”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kchj  ubhŒblock_quote”“”)”}”(hŒölikelihood of failure injection, in percent.

Format: <percent>

Note that one-failure-per-hundred is a very high error rate
for some testcases.  Consider setting probability=100 and configure
/sys/kernel/debug/fail*/interval for such testcases.
”h]”(hÌ)”}”(hŒ,likelihood of failure injection, in percent.”h]”hŒ,likelihood of failure injection, in percent.”…””}”(hj(  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kehj$  ubhÌ)”}”(hŒFormat: <percent>”h]”hŒFormat: <percent>”…””}”(hj6  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kghj$  ubhÌ)”}”(hŒ´Note that one-failure-per-hundred is a very high error rate
for some testcases.  Consider setting probability=100 and configure
/sys/kernel/debug/fail*/interval for such testcases.”h]”hŒ´Note that one-failure-per-hundred is a very high error rate
for some testcases.  Consider setting probability=100 and configure
/sys/kernel/debug/fail*/interval for such testcases.”…””}”(hjD  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kihj$  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Kehj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hX  /sys/kernel/debug/fail*/interval:

      specifies the interval between failures, for calls to
      should_fail() that pass all the other tests.

      Note that if you enable this, by setting interval>1, you will
      probably want to set probability=100.
”h]”(hÌ)”}”(hŒ!/sys/kernel/debug/fail*/interval:”h]”hŒ!/sys/kernel/debug/fail*/interval:”…””}”(hjb  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kmhj^  ubj#  )”}”(hŒÈspecifies the interval between failures, for calls to
should_fail() that pass all the other tests.

Note that if you enable this, by setting interval>1, you will
probably want to set probability=100.
”h]”(hÌ)”}”(hŒbspecifies the interval between failures, for calls to
should_fail() that pass all the other tests.”h]”hŒbspecifies the interval between failures, for calls to
should_fail() that pass all the other tests.”…””}”(hjt  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kohjp  ubhÌ)”}”(hŒcNote that if you enable this, by setting interval>1, you will
probably want to set probability=100.”h]”hŒcNote that if you enable this, by setting interval>1, you will
probably want to set probability=100.”…””}”(hj‚  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Krhjp  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Kohj^  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒ‚/sys/kernel/debug/fail*/times:

      specifies how many times failures may happen at most. A value of -1
      means "no limit".
”h]”(hÌ)”}”(hŒ/sys/kernel/debug/fail*/times:”h]”hŒ/sys/kernel/debug/fail*/times:”…””}”(hj   h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kuhjœ  ubj#  )”}”(hŒVspecifies how many times failures may happen at most. A value of -1
means "no limit".
”h]”hÌ)”}”(hŒUspecifies how many times failures may happen at most. A value of -1
means "no limit".”h]”hŒYspecifies how many times failures may happen at most. A value of -1
means â€œno limitâ€.”…””}”(hj²  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kwhj®  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Kwhjœ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒÑ/sys/kernel/debug/fail*/space:

      specifies an initial resource "budget", decremented by "size"
      on each call to should_fail(,size).  Failure injection is
      suppressed until "space" reaches zero.
”h]”(hÌ)”}”(hŒ/sys/kernel/debug/fail*/space:”h]”hŒ/sys/kernel/debug/fail*/space:”…””}”(hjÐ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KzhjÌ  ubj#  )”}”(hŒŸspecifies an initial resource "budget", decremented by "size"
on each call to should_fail(,size).  Failure injection is
suppressed until "space" reaches zero.
”h]”hÌ)”}”(hŒžspecifies an initial resource "budget", decremented by "size"
on each call to should_fail(,size).  Failure injection is
suppressed until "space" reaches zero.”h]”hŒªspecifies an initial resource â€œbudgetâ€, decremented by â€œsizeâ€
on each call to should_fail(,size).  Failure injection is
suppressed until â€œspaceâ€ reaches zero.”…””}”(hjâ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K|hjÞ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K|hjÌ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hX@  /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
      to debug the problems revealed by fault injection.
”h]”(hÌ)”}”(hŒ/sys/kernel/debug/fail*/verbose”h]”hŒ/sys/kernel/debug/fail*/verbose”…””}”(hj   h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K€hjü  ubj#  )”}”(hX  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
to debug the problems revealed by fault injection.
”h]”(hÌ)”}”(hŒFormat: { 0 | 1 | 2 }”h]”hŒFormat: { 0 | 1 | 2 }”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K‚hj  ubhÌ)”}”(hŒéspecifies the verbosity of the messages when failure is
injected.  '0' means no messages; '1' will print only a single
log line per failure; '2' will print a call trace too -- useful
to debug the problems revealed by fault injection.”h]”hŒõspecifies the verbosity of the messages when failure is
injected.  â€˜0â€™ means no messages; â€˜1â€™ will print only a single
log line per failure; â€˜2â€™ will print a call trace too -- useful
to debug the problems revealed by fault injection.”…””}”(hj   h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K„hj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K‚hjü  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒì/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.
”h]”(hÌ)”}”(hŒ$/sys/kernel/debug/fail*/task-filter:”h]”hŒ$/sys/kernel/debug/fail*/task-filter:”…””}”(hj>  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K‰hj:  ubj#  )”}”(hŒ®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.
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hjP  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K‹hjL  ubhÌ)”}”(hŒ–A value of 'N' disables filtering by process (default).
Any positive value limits failures to only processes indicated by
/proc/<pid>/make-it-fail==1.”h]”hŒšA value of â€˜Nâ€™ disables filtering by process (default).
Any positive value limits failures to only processes indicated by
/proc/<pid>/make-it-fail==1.”…””}”(hj^  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KhjL  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K‹hj:  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hXü  /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
      in the walked stacktrace lies within the required range, and
      none lies within the rejected range.
      Default required range is [0,ULONG_MAX) (whole of virtual address space).
      Default rejected range is [0,0).
”h]”(hÌ)”}”(hŒ•/sys/kernel/debug/fail*/require-start,
/sys/kernel/debug/fail*/require-end,
/sys/kernel/debug/fail*/reject-start,
/sys/kernel/debug/fail*/reject-end:”h]”hŒ•/sys/kernel/debug/fail*/require-start,
/sys/kernel/debug/fail*/require-end,
/sys/kernel/debug/fail*/reject-start,
/sys/kernel/debug/fail*/reject-end:”…””}”(hj|  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K‘hjx  ubj#  )”}”(hXA  specifies the range of virtual addresses tested during
stacktrace walking.  Failure is injected only if some caller
in the walked stacktrace lies within the required range, and
none lies within the rejected range.
Default required range is [0,ULONG_MAX) (whole of virtual address space).
Default rejected range is [0,0).
”h]”hÌ)”}”(hX@  specifies the range of virtual addresses tested during
stacktrace walking.  Failure is injected only if some caller
in the walked stacktrace lies within the required range, and
none lies within the rejected range.
Default required range is [0,ULONG_MAX) (whole of virtual address space).
Default rejected range is [0,0).”h]”hX@  specifies the range of virtual addresses tested during
stacktrace walking.  Failure is injected only if some caller
in the walked stacktrace lies within the required range, and
none lies within the rejected range.
Default required range is [0,ULONG_MAX) (whole of virtual address space).
Default rejected range is [0,0).”…””}”(hjŽ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K–hjŠ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K–hjx  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒÇ/sys/kernel/debug/fail*/stacktrace-depth:

      specifies the maximum stacktrace depth walked during search
      for a caller within [require-start,require-end) OR
      [reject-start,reject-end).
”h]”(hÌ)”}”(hŒ)/sys/kernel/debug/fail*/stacktrace-depth:”h]”hŒ)/sys/kernel/debug/fail*/stacktrace-depth:”…””}”(hj¬  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj¨  ubj#  )”}”(hŒŠspecifies the maximum stacktrace depth walked during search
for a caller within [require-start,require-end) OR
[reject-start,reject-end).
”h]”hÌ)”}”(hŒ‰specifies the maximum stacktrace depth walked during search
for a caller within [require-start,require-end) OR
[reject-start,reject-end).”h]”hŒ‰specifies the maximum stacktrace depth walked during search
for a caller within [require-start,require-end) OR
[reject-start,reject-end).”…””}”(hj¾  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KŸhjº  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´KŸhj¨  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒ×/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:

      Format: { 'Y' | 'N' }

      default is 'Y', setting it to 'N' will also inject failures into
      highmem/user allocations (__GFP_HIGHMEM allocations).
”h]”(hÌ)”}”(hŒ5/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:”h]”hŒ5/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem:”…””}”(hjÜ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K£hjØ  ubj#  )”}”(hŒŽFormat: { 'Y' | 'N' }

default is 'Y', setting it to 'N' will also inject failures into
highmem/user allocations (__GFP_HIGHMEM allocations).
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hjî  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K¥hjê  ubhÌ)”}”(hŒvdefault is 'Y', setting it to 'N' will also inject failures into
highmem/user allocations (__GFP_HIGHMEM allocations).”h]”hŒ~default is â€˜Yâ€™, setting it to â€˜Nâ€™ will also inject failures into
highmem/user allocations (__GFP_HIGHMEM allocations).”…””}”(hjü  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K§hjê  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K¥hjØ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hX	  /sys/kernel/debug/failslab/cache-filter
      Format: { 'Y' | 'N' }

      default is 'N', setting it to 'Y' will only inject failures when
      objects are requests from certain caches.

      Select the cache by writing '1' to /sys/kernel/slab/<cache>/failslab:
”h]”hŒdefinition_list”“”)”}”(hhh]”hŒdefinition_list_item”“”)”}”(hŒñ/sys/kernel/debug/failslab/cache-filter
Format: { 'Y' | 'N' }

default is 'N', setting it to 'Y' will only inject failures when
objects are requests from certain caches.

Select the cache by writing '1' to /sys/kernel/slab/<cache>/failslab:
”h]”(hŒterm”“”)”}”(hŒ'/sys/kernel/debug/failslab/cache-filter”h]”hŒ'/sys/kernel/debug/failslab/cache-filter”…””}”(hj'  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j%  h³hÊh´K°hj!  ubhŒ
definition”“”)”}”(hhh]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hj:  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K«hj7  ubhÌ)”}”(hŒjdefault is 'N', setting it to 'Y' will only inject failures when
objects are requests from certain caches.”h]”hŒrdefault is â€˜Nâ€™, setting it to â€˜Yâ€™ will only inject failures when
objects are requests from certain caches.”…””}”(hjH  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K­hj7  ubhÌ)”}”(hŒESelect the cache by writing '1' to /sys/kernel/slab/<cache>/failslab:”h]”hŒISelect the cache by writing â€˜1â€™ to /sys/kernel/slab/<cache>/failslab:”…””}”(hjV  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K°hj7  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j5  hj!  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j  h³hÊh´K°hj  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j  hj  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³Nh´Nubhò)”}”(hŒ+/sys/kernel/debug/failslab/ignore-gfp-wait:”h]”hÌ)”}”(hj~  h]”hŒ+/sys/kernel/debug/failslab/ignore-gfp-wait:”…””}”(hj€  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K²hj|  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒÝ/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:

      Format: { 'Y' | 'N' }

      default is 'Y', setting it to 'N' will also inject failures
      into allocations that can sleep (__GFP_DIRECT_RECLAIM allocations).
”h]”(hÌ)”}”(hŒ2/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:”h]”hŒ2/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait:”…””}”(hj—  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K³hj“  ubj#  )”}”(hŒ—Format: { 'Y' | 'N' }

default is 'Y', setting it to 'N' will also inject failures
into allocations that can sleep (__GFP_DIRECT_RECLAIM allocations).
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hj©  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kµhj¥  ubhÌ)”}”(hŒdefault is 'Y', setting it to 'N' will also inject failures
into allocations that can sleep (__GFP_DIRECT_RECLAIM allocations).”h]”hŒ‡default is â€˜Yâ€™, setting it to â€˜Nâ€™ will also inject failures
into allocations that can sleep (__GFP_DIRECT_RECLAIM allocations).”…””}”(hj·  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K·hj¥  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Kµhj“  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒ/sys/kernel/debug/fail_page_alloc/min-order:

      specifies the minimum page allocation order to be injected
      failures.
”h]”(hÌ)”}”(hŒ,/sys/kernel/debug/fail_page_alloc/min-order:”h]”hŒ,/sys/kernel/debug/fail_page_alloc/min-order:”…””}”(hjÕ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KºhjÑ  ubj#  )”}”(hŒEspecifies the minimum page allocation order to be injected
failures.
”h]”hÌ)”}”(hŒDspecifies the minimum page allocation order to be injected
failures.”h]”hŒDspecifies the minimum page allocation order to be injected
failures.”…””}”(hjç  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K¼hjã  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K¼hjÑ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒÌ/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.
”h]”(hÌ)”}”(hŒ,/sys/kernel/debug/fail_futex/ignore-private:”h]”hŒ,/sys/kernel/debug/fail_futex/ignore-private:”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K¿hj  ubj#  )”}”(hŒŒFormat: { 'Y' | 'N' }

default is 'N', setting it to 'Y' will disable failure injections
when dealing with private (address space) futexes.
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÁhj  ubhÌ)”}”(hŒtdefault is 'N', setting it to 'Y' will disable failure injections
when dealing with private (address space) futexes.”h]”hŒ|default is â€˜Nâ€™, setting it to â€˜Yâ€™ will disable failure injections
when dealing with private (address space) futexes.”…””}”(hj%  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÃhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´KÁhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒ¹/sys/kernel/debug/fail_sunrpc/ignore-client-disconnect:

      Format: { 'Y' | 'N' }

      default is 'N', setting it to 'Y' will disable disconnect
      injection on the RPC client.
”h]”(hÌ)”}”(hŒ7/sys/kernel/debug/fail_sunrpc/ignore-client-disconnect:”h]”hŒ7/sys/kernel/debug/fail_sunrpc/ignore-client-disconnect:”…””}”(hjC  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÆhj?  ubj#  )”}”(hŒnFormat: { 'Y' | 'N' }

default is 'N', setting it to 'Y' will disable disconnect
injection on the RPC client.
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hjU  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÈhjQ  ubhÌ)”}”(hŒVdefault is 'N', setting it to 'Y' will disable disconnect
injection on the RPC client.”h]”hŒ^default is â€˜Nâ€™, setting it to â€˜Yâ€™ will disable disconnect
injection on the RPC client.”…””}”(hjc  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÊhjQ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´KÈhj?  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒ¹/sys/kernel/debug/fail_sunrpc/ignore-server-disconnect:

      Format: { 'Y' | 'N' }

      default is 'N', setting it to 'Y' will disable disconnect
      injection on the RPC server.
”h]”(hÌ)”}”(hŒ7/sys/kernel/debug/fail_sunrpc/ignore-server-disconnect:”h]”hŒ7/sys/kernel/debug/fail_sunrpc/ignore-server-disconnect:”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÍhj}  ubj#  )”}”(hŒnFormat: { 'Y' | 'N' }

default is 'N', setting it to 'Y' will disable disconnect
injection on the RPC server.
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hj“  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÏhj  ubhÌ)”}”(hŒVdefault is 'N', setting it to 'Y' will disable disconnect
injection on the RPC server.”h]”hŒ^default is â€˜Nâ€™, setting it to â€˜Yâ€™ will disable disconnect
injection on the RPC server.”…””}”(hj¡  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÑhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´KÏhj}  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hŒ²/sys/kernel/debug/fail_sunrpc/ignore-cache-wait:

      Format: { 'Y' | 'N' }

      default is 'N', setting it to 'Y' will disable cache wait
      injection on the RPC server.
”h]”(hÌ)”}”(hŒ0/sys/kernel/debug/fail_sunrpc/ignore-cache-wait:”h]”hŒ0/sys/kernel/debug/fail_sunrpc/ignore-cache-wait:”…””}”(hj¿  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÔhj»  ubj#  )”}”(hŒnFormat: { 'Y' | 'N' }

default is 'N', setting it to 'Y' will disable cache wait
injection on the RPC server.
”h]”(hÌ)”}”(hŒFormat: { 'Y' | 'N' }”h]”hŒFormat: { â€˜Yâ€™ | â€˜Nâ€™ }”…””}”(hjÑ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÖhjÍ  ubhÌ)”}”(hŒVdefault is 'N', setting it to 'Y' will disable cache wait
injection on the RPC server.”h]”hŒ^default is â€˜Nâ€™, setting it to â€˜Yâ€™ will disable cache wait
injection on the RPC server.”…””}”(hjß  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KØhjÍ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´KÖhj»  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hXA  /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 ('')
      injection list is cleared.
”h]”(hÌ)”}”(hŒ'/sys/kernel/debug/fail_function/inject:”h]”hŒ'/sys/kernel/debug/fail_function/inject:”…””}”(hjý  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÛhjù  ubj#  )”}”(hŒúFormat: { '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 ('')
injection list is cleared.
”h]”(hÌ)”}”(hŒ3Format: { 'function-name' | '!function-name' | '' }”h]”hŒ?Format: { â€˜function-nameâ€™ | â€˜!function-nameâ€™ | â€˜â€™ }”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KÝhj  ubhÌ)”}”(hŒÄspecifies the target function of error injection by name.
If the function name leads '!' prefix, given function is
removed from injection list. If nothing specified ('')
injection list is cleared.”h]”hŒÌspecifies the target function of error injection by name.
If the function name leads â€˜!â€™ prefix, given function is
removed from injection list. If nothing specified (â€˜â€™)
injection list is cleared.”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kßhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´KÝhjù  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hXY  /sys/kernel/debug/fail_function/injectable:

      (read only) shows error injectable functions and what type of
      error values can be specified. The error type will be one of
      below;
      - NULL: retval must be 0.
      - ERRNO: retval must be -1 to -MAX_ERRNO (-4096).
      - ERR_NULL: retval must be 0 or -1 to -MAX_ERRNO (-4096).
”h]”(hÌ)”}”(hŒ+/sys/kernel/debug/fail_function/injectable:”h]”hŒ+/sys/kernel/debug/fail_function/injectable:”…””}”(hj;  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kähj7  ubj#  )”}”(hX  (read only) shows error injectable functions and what type of
error values can be specified. The error type will be one of
below;
- NULL: retval must be 0.
- ERRNO: retval must be -1 to -MAX_ERRNO (-4096).
- ERR_NULL: retval must be 0 or -1 to -MAX_ERRNO (-4096).
”h]”hÌ)”}”(hX  (read only) shows error injectable functions and what type of
error values can be specified. The error type will be one of
below;
- NULL: retval must be 0.
- ERRNO: retval must be -1 to -MAX_ERRNO (-4096).
- ERR_NULL: retval must be 0 or -1 to -MAX_ERRNO (-4096).”h]”hX  (read only) shows error injectable functions and what type of
error values can be specified. The error type will be one of
below;
- NULL: retval must be 0.
- ERRNO: retval must be -1 to -MAX_ERRNO (-4096).
- ERR_NULL: retval must be 0 or -1 to -MAX_ERRNO (-4096).”…””}”(hjM  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KæhjI  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Kæhj7  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hX…  /sys/kernel/debug/fail_function/<function-name>/retval:

      specifies the "error" return value to inject to the given function.
      This will be created when the user specifies a new injection entry.
      Note that this file only accepts unsigned values. So, if you want to
      use a negative errno, you better use 'printf' instead of 'echo', e.g.:
      $ printf %#x -12 > retval
”h]”(hÌ)”}”(hŒ7/sys/kernel/debug/fail_function/<function-name>/retval:”h]”hŒ7/sys/kernel/debug/fail_function/<function-name>/retval:”…””}”(hjk  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kíhjg  ubj#  )”}”(hX.  specifies the "error" return value to inject to the given function.
This will be created when the user specifies a new injection entry.
Note that this file only accepts unsigned values. So, if you want to
use a negative errno, you better use 'printf' instead of 'echo', e.g.:
$ printf %#x -12 > retval
”h]”hÌ)”}”(hX-  specifies the "error" return value to inject to the given function.
This will be created when the user specifies a new injection entry.
Note that this file only accepts unsigned values. So, if you want to
use a negative errno, you better use 'printf' instead of 'echo', e.g.:
$ printf %#x -12 > retval”h]”hX9  specifies the â€œerrorâ€ return value to inject to the given function.
This will be created when the user specifies a new injection entry.
Note that this file only accepts unsigned values. So, if you want to
use a negative errno, you better use â€˜printfâ€™ instead of â€˜echoâ€™, e.g.:
$ printf %#x -12 > retval”…””}”(hj}  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kïhjy  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Kïhjg  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubhò)”}”(hXÔ  /sys/kernel/debug/fail_skb_realloc/devname:

      Specifies the network interface on which to force SKB reallocation.  If
      left empty, SKB reallocation will be applied to all network interfaces.

      Example usage::

        # Force skb reallocation on eth0
        echo "eth0" > /sys/kernel/debug/fail_skb_realloc/devname

        # Clear the selection and force skb reallocation on all interfaces
        echo "" > /sys/kernel/debug/fail_skb_realloc/devname
”h]”(hÌ)”}”(hŒ+/sys/kernel/debug/fail_skb_realloc/devname:”h]”hŒ+/sys/kernel/debug/fail_skb_realloc/devname:”…””}”(hj›  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kõhj—  ubj#  )”}”(hX}  Specifies the network interface on which to force SKB reallocation.  If
left empty, SKB reallocation will be applied to all network interfaces.

Example usage::

  # Force skb reallocation on eth0
  echo "eth0" > /sys/kernel/debug/fail_skb_realloc/devname

  # Clear the selection and force skb reallocation on all interfaces
  echo "" > /sys/kernel/debug/fail_skb_realloc/devname
”h]”(hÌ)”}”(hŒSpecifies the network interface on which to force SKB reallocation.  If
left empty, SKB reallocation will be applied to all network interfaces.”h]”hŒSpecifies the network interface on which to force SKB reallocation.  If
left empty, SKB reallocation will be applied to all network interfaces.”…””}”(hj­  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K÷hj©  ubhÌ)”}”(hŒExample usage::”h]”hŒExample usage:”…””}”(hj»  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Kúhj©  ubhŒliteral_block”“”)”}”(hŒÒ# Force skb reallocation on eth0
echo "eth0" > /sys/kernel/debug/fail_skb_realloc/devname

# Clear the selection and force skb reallocation on all interfaces
echo "" > /sys/kernel/debug/fail_skb_realloc/devname”h]”hŒÒ# Force skb reallocation on eth0
echo "eth0" > /sys/kernel/debug/fail_skb_realloc/devname

# Clear the selection and force skb reallocation on all interfaces
echo "" > /sys/kernel/debug/fail_skb_realloc/devname”…””}”hjË  sbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1jÉ  h³hÊh´Kühj©  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´K÷hj—  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj  h²hh³hÊh´Nubeh}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´Kchjî  h²hubeh}”(h]”Œdebugfs-entries”ah ]”h"]”Œdebugfs entries”ah$]”h&]”uh1hµhjÝ  h²hh³hÊh´K^ubh¶)”}”(hhh]”(h»)”}”(hŒBoot option”h]”hŒBoot option”…””}”(hjø  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhjõ  h²hh³hÊh´MubhÌ)”}”(hŒaIn order to inject faults while debugfs is not available (early boot time),
use the boot option::”h]”hŒ`In order to inject faults while debugfs is not available (early boot time),
use the boot option:”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhjõ  h²hubjÊ  )”}”(hŒ™failslab=
fail_page_alloc=
fail_usercopy=
fail_make_request=
fail_futex=
fail_skb_realloc=
mmc_core.fail_request=<interval>,<probability>,<space>,<times>”h]”hŒ™failslab=
fail_page_alloc=
fail_usercopy=
fail_make_request=
fail_futex=
fail_skb_realloc=
mmc_core.fail_request=<interval>,<probability>,<space>,<times>”…””}”hj  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´Mhjõ  h²hubeh}”(h]”Œboot-option”ah ]”h"]”Œboot option”ah$]”h&]”uh1hµhjÝ  h²hh³hÊh´Mubh¶)”}”(hhh]”(h»)”}”(hŒproc entries”h]”hŒproc entries”…””}”(hj-  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj*  h²hh³hÊh´Mubhí)”}”(hhh]”hò)”}”(hX÷  /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
      that the fault setup with a previous write to this file was injected.
      A positive integer N indicates that the fault wasn't yet injected.
      Note that this file enables all types of faults (slab, futex, etc).
      This setting takes precedence over all other generic debugfs settings
      like probability, interval, times, etc. But per-capability settings
      (e.g. fail_futex/ignore-private) take precedence over it.

      This feature is intended for systematic testing of faults in a single
      system call. See an example below.

”h]”(hÌ)”}”(hŒ5/proc/<pid>/fail-nth,
/proc/self/task/<tid>/fail-nth:”h]”hŒ5/proc/<pid>/fail-nth,
/proc/self/task/<tid>/fail-nth:”…””}”(hjB  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj>  ubj#  )”}”(hX„  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
that the fault setup with a previous write to this file was injected.
A positive integer N indicates that the fault wasn't yet injected.
Note that this file enables all types of faults (slab, futex, etc).
This setting takes precedence over all other generic debugfs settings
like probability, interval, times, etc. But per-capability settings
(e.g. fail_futex/ignore-private) take precedence over it.

This feature is intended for systematic testing of faults in a single
system call. See an example below.

”h]”(hÌ)”}”(hX  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
that the fault setup with a previous write to this file was injected.
A positive integer N indicates that the fault wasn't yet injected.
Note that this file enables all types of faults (slab, futex, etc).
This setting takes precedence over all other generic debugfs settings
like probability, interval, times, etc. But per-capability settings
(e.g. fail_futex/ignore-private) take precedence over it.”h]”hX  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 â€˜0â€™ indicates
that the fault setup with a previous write to this file was injected.
A positive integer N indicates that the fault wasnâ€™t yet injected.
Note that this file enables all types of faults (slab, futex, etc).
This setting takes precedence over all other generic debugfs settings
like probability, interval, times, etc. But per-capability settings
(e.g. fail_futex/ignore-private) take precedence over it.”…””}”(hjT  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MhjP  ubhÌ)”}”(hŒhThis feature is intended for systematic testing of faults in a single
system call. See an example below.”h]”hŒhThis feature is intended for systematic testing of faults in a single
system call. See an example below.”…””}”(hjb  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MhjP  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Mhj>  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj;  h²hh³hÊh´Nubah}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´Mhj*  h²hubeh}”(h]”Œproc-entries”ah ]”h"]”Œproc entries”ah$]”h&]”uh1hµhjÝ  h²hh³hÊh´Mubeh}”(h]”Œ/configure-fault-injection-capabilities-behavior”ah ]”h"]”Œ/configure fault-injection capabilities behavior”ah$]”h&]”uh1hµhh·h²hh³hÊh´K[ubh¶)”}”(hhh]”(h»)”}”(hŒError Injectable Functions”h]”hŒError Injectable Functions”…””}”(hj•  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj’  h²hh³hÊh´M$ubhÌ)”}”(hŒfThis part is for the kernel developers considering to add a function to
ALLOW_ERROR_INJECTION() macro.”h]”hŒfThis part is for the kernel developers considering to add a function to
ALLOW_ERROR_INJECTION() macro.”…””}”(hj£  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M&hj’  h²hubh¶)”}”(hhh]”(h»)”}”(hŒ/Requirements for the Error Injectable Functions”h]”hŒ/Requirements for the Error Injectable Functions”…””}”(hj´  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj±  h²hh³hÊh´M*ubhÌ)”}”(hX#  Since the function-level error injection forcibly changes the code path
and returns an error even if the input and conditions are proper, this can
cause unexpected kernel crash if you allow error injection on the function
which is NOT error injectable. Thus, you (and reviewers) must ensure;”h]”hX#  Since the function-level error injection forcibly changes the code path
and returns an error even if the input and conditions are proper, this can
cause unexpected kernel crash if you allow error injection on the function
which is NOT error injectable. Thus, you (and reviewers) must ensure;”…””}”(hjÂ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M,hj±  h²hubhí)”}”(hhh]”(hò)”}”(hŒsThe function returns an error code if it fails, and the callers must check
it correctly (need to recover from it).
”h]”hÌ)”}”(hŒrThe function returns an error code if it fails, and the callers must check
it correctly (need to recover from it).”h]”hŒrThe function returns an error code if it fails, and the callers must check
it correctly (need to recover from it).”…””}”(hj×  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M1hjÓ  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÐ  h²hh³hÊh´Nubhò)”}”(hXg  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.)
”h]”hÌ)”}”(hXf  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.)”h]”(hŒÈThe 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. ”…””}”(hjï  h²hh³Nh´NubhŒtitle_reference”“”)”}”(hŒ`*ret = NULL`”h]”hŒ*ret = NULL”…””}”(hjù  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hjï  ubhŒ‘),
increments/decrements counter, set a flag, preempt/irq disable or get
a lock (if those are recovered before returning error, that will be OK.)”…””}”(hjï  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M4hjë  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÐ  h²hh³hÊh´Nubeh}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´M1hj±  h²hubhÌ)”}”(hXK  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.)”h]”hXK  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.)”…””}”(hj	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M:hj±  h²hubhÌ)”}”(hŒ×The second one is for the caller which expects the function should always
does something. Thus if the function error injection skips whole of the
function, the expectation is betrayed and causes an unexpected error.”h]”hŒ×The second one is for the caller which expects the function should always
does something. Thus if the function error injection skips whole of the
function, the expectation is betrayed and causes an unexpected error.”…””}”(hj+	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M@hj±  h²hubeh}”(h]”Œ/requirements-for-the-error-injectable-functions”ah ]”h"]”Œ/requirements for the error injectable functions”ah$]”h&]”uh1hµhj’  h²hh³hÊh´M*ubh¶)”}”(hhh]”(h»)”}”(hŒ&Type of the Error Injectable Functions”h]”hŒ&Type of the Error Injectable Functions”…””}”(hjD	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhjA	  h²hh³hÊh´MEubhÌ)”}”(hXi  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”h]”hXi  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”…””}”(hjR	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MGhjA	  h²hubj  )”}”(hhh]”(j   )”}”(hŒeEI_ETYPE_NULL
This function will return `NULL` if it fails. e.g. return an allocated
object address.
”h]”(j&  )”}”(hŒEI_ETYPE_NULL”h]”hŒEI_ETYPE_NULL”…””}”(hjg	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j%  h³hÊh´MOhjc	  ubj6  )”}”(hhh]”hÌ)”}”(hŒVThis function will return `NULL` if it fails. e.g. return an allocated
object address.”h]”(hŒThis function will return ”…””}”(hjx	  h²hh³Nh´Nubjø  )”}”(hŒ`NULL`”h]”hŒNULL”…””}”(hj€	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hjx	  ubhŒ6 if it fails. e.g. return an allocated
object address.”…””}”(hjx	  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MNhju	  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j5  hjc	  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j  h³hÊh´MOhj`	  ubj   )”}”(hŒàEI_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.
”h]”(j&  )”}”(hŒEI_ETYPE_ERRNO”h]”hŒEI_ETYPE_ERRNO”…””}”(hj¨	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j%  h³hÊh´MThj¤	  ubj6  )”}”(hhh]”hÌ)”}”(hŒÐThis function will return an `-errno` error code if it fails. e.g. return
-EINVAL if the input is wrong. This will include the functions which will
return an address which encodes `-errno` by ERR_PTR() macro.”h]”(hŒThis function will return an ”…””}”(hj¹	  h²hh³Nh´Nubjø  )”}”(hŒ`-errno`”h]”hŒ-errno”…””}”(hjÁ	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hj¹	  ubhŒ 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 ”…””}”(hj¹	  h²hh³Nh´Nubjø  )”}”(hŒ`-errno`”h]”hŒ-errno”…””}”(hjÓ	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hj¹	  ubhŒ by ERR_PTR() macro.”…””}”(hj¹	  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MRhj¶	  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j5  hj¤	  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j  h³hÊh´MThj`	  h²hubj   )”}”(hŒÄEI_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.
”h]”(j&  )”}”(hŒEI_ETYPE_ERRNO_NULL”h]”hŒEI_ETYPE_ERRNO_NULL”…””}”(hjû	  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j%  h³hÊh´MYhj÷	  ubj6  )”}”(hhh]”hÌ)”}”(hŒ¯This function will return an `-errno` or `NULL` if it fails. If the caller
of this function checks the return value with IS_ERR_OR_NULL() macro, this
type will be appropriate.”h]”(hŒThis function will return an ”…””}”(hj
  h²hh³Nh´Nubjø  )”}”(hŒ`-errno`”h]”hŒ-errno”…””}”(hj
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hj
  ubhŒ or ”…””}”(hj
  h²hh³Nh´Nubjø  )”}”(hŒ`NULL`”h]”hŒNULL”…””}”(hj&
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hj
  ubhŒ€ if it fails. If the caller
of this function checks the return value with IS_ERR_OR_NULL() macro, this
type will be appropriate.”…””}”(hj
  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MWhj	
  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j5  hj÷	  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j  h³hÊh´MYhj`	  h²hubj   )”}”(hŒVEI_ETYPE_TRUE
This function will return `true` (non-zero positive value) if it fails.
”h]”(j&  )”}”(hŒEI_ETYPE_TRUE”h]”hŒEI_ETYPE_TRUE”…””}”(hjN
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j%  h³hÊh´M\hjJ
  ubj6  )”}”(hhh]”hÌ)”}”(hŒGThis function will return `true` (non-zero positive value) if it fails.”h]”(hŒThis function will return ”…””}”(hj_
  h²hh³Nh´Nubjø  )”}”(hŒ`true`”h]”hŒtrue”…””}”(hjg
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j÷  hj_
  ubhŒ' (non-zero positive value) if it fails.”…””}”(hj_
  h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M\hj\
  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j5  hjJ
  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j  h³hÊh´M\hj`	  h²hubeh}”(h]”h ]”h"]”h$]”h&]”uh1j  hjA	  h²hh³hÊh´NubhÌ)”}”(hŒæIf 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.”h]”hŒæIf 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.”…””}”(hj‘
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M^hjA	  h²hubeh}”(h]”Œ&type-of-the-error-injectable-functions”ah ]”h"]”Œ&type of the error injectable functions”ah$]”h&]”uh1hµhj’  h²hh³hÊh´MEubeh}”(h]”Œerror-injectable-functions”ah ]”h"]”Œerror injectable functions”ah$]”h&]”uh1hµhh·h²hh³hÊh´M$ubh¶)”}”(hhh]”(h»)”}”(hŒ)How to add new fault injection capability”h]”hŒ)How to add new fault injection capability”…””}”(hj²
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj¯
  h²hh³hÊh´Mdubhí)”}”(hhh]”(hò)”}”(hŒ #include <linux/fault-inject.h>
”h]”hÌ)”}”(hŒ#include <linux/fault-inject.h>”h]”hŒ#include <linux/fault-inject.h>”…””}”(hjÇ
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MfhjÃ
  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubhò)”}”(hŒ†define the fault attributes

DECLARE_FAULT_ATTR(name);

Please see the definition of struct fault_attr in fault-inject.h
for details.
”h]”(hÌ)”}”(hŒdefine the fault attributes”h]”hŒdefine the fault attributes”…””}”(hjß
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MhhjÛ
  ubhÌ)”}”(hŒDECLARE_FAULT_ATTR(name);”h]”hŒDECLARE_FAULT_ATTR(name);”…””}”(hjí
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MjhjÛ
  ubhÌ)”}”(hŒMPlease see the definition of struct fault_attr in fault-inject.h
for details.”h]”hŒMPlease see the definition of struct fault_attr in fault-inject.h
for details.”…””}”(hjû
  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MlhjÛ
  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubhò)”}”(hŒ,provide a way to configure fault attributes
”h]”hÌ)”}”(hŒ+provide a way to configure fault attributes”h]”hŒ+provide a way to configure fault attributes”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mohj  ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubhò)”}”(hŒÆboot option

If you need to enable the fault injection capability from boot time, you can
provide boot option to configure it. There is a helper function for it:

      setup_fault_attr(attr, str);
”h]”(hÌ)”}”(hŒboot option”h]”hŒboot option”…””}”(hj+  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mqhj'  ubhÌ)”}”(hŒ”If you need to enable the fault injection capability from boot time, you can
provide boot option to configure it. There is a helper function for it:”h]”hŒ”If you need to enable the fault injection capability from boot time, you can
provide boot option to configure it. There is a helper function for it:”…””}”(hj9  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mshj'  ubj#  )”}”(hŒsetup_fault_attr(attr, str);
”h]”hÌ)”}”(hŒsetup_fault_attr(attr, str);”h]”hŒsetup_fault_attr(attr, str);”…””}”(hjK  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MvhjG  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´Mvhj'  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubhò)”}”(hŒ§debugfs entries

failslab, fail_page_alloc, fail_usercopy, and fail_make_request use this way.
Helper functions:

      fault_create_debugfs_attr(name, parent, attr);
”h]”(hÌ)”}”(hŒdebugfs entries”h]”hŒdebugfs entries”…””}”(hji  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mxhje  ubhÌ)”}”(hŒ_failslab, fail_page_alloc, fail_usercopy, and fail_make_request use this way.
Helper functions:”h]”hŒ_failslab, fail_page_alloc, fail_usercopy, and fail_make_request use this way.
Helper functions:”…””}”(hjw  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mzhje  ubj#  )”}”(hŒ/fault_create_debugfs_attr(name, parent, attr);
”h]”hÌ)”}”(hŒ.fault_create_debugfs_attr(name, parent, attr);”h]”hŒ.fault_create_debugfs_attr(name, parent, attr);”…””}”(hj‰  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M}hj…  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´M}hje  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubhò)”}”(hŒµmodule parameters

If the scope of the fault injection capability is limited to a
single kernel module, it is better to provide module parameters to
configure the fault attributes.
”h]”(hÌ)”}”(hŒmodule parameters”h]”hŒmodule parameters”…””}”(hj§  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj£  ubhÌ)”}”(hŒ¡If the scope of the fault injection capability is limited to a
single kernel module, it is better to provide module parameters to
configure the fault attributes.”h]”hŒ¡If the scope of the fault injection capability is limited to a
single kernel module, it is better to provide module parameters to
configure the fault attributes.”…””}”(hjµ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj£  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubhò)”}”(hŒ‡add a hook to insert failures

Upon should_fail() returning true, client code should inject a failure:

      should_fail(attr, size);
”h]”(hÌ)”}”(hŒadd a hook to insert failures”h]”hŒadd a hook to insert failures”…””}”(hjÍ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M…hjÉ  ubhÌ)”}”(hŒGUpon should_fail() returning true, client code should inject a failure:”h]”hŒGUpon should_fail() returning true, client code should inject a failure:”…””}”(hjÛ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M‡hjÉ  ubj#  )”}”(hŒshould_fail(attr, size);
”h]”hÌ)”}”(hŒshould_fail(attr, size);”h]”hŒshould_fail(attr, size);”…””}”(hjí  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M‰hjé  ubah}”(h]”h ]”h"]”h$]”h&]”uh1j"  h³hÊh´M‰hjÉ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÀ
  h²hh³hÊh´Nubeh}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´Mfhj¯
  h²hubeh}”(h]”Œ)how-to-add-new-fault-injection-capability”ah ]”h"]”Œ)how to add new fault injection capability”ah$]”h&]”uh1hµhh·h²hh³hÊh´Mdubh¶)”}”(hhh]”(h»)”}”(hŒApplication Examples”h]”hŒApplication Examples”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj  h²hh³hÊh´MŒubhí)”}”(hhh]”hò)”}”(hX  Inject slab allocation failures into module init/exit code::

  #!/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 Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait

  faulty_system()
  {
      bash -c "echo 1 > /proc/self/make-it-fail && exec $*"
  }

  if [ $# -eq 0 ]
  then
      echo "Usage: $0 modulename [ modulename ... ]"
      exit 1
  fi

  for m in $*
  do
      echo inserting $m...
      faulty_system modprobe $m

      echo removing $m...
      faulty_system modprobe -r $m
  done
”h]”(hÌ)”}”(hŒ<Inject slab allocation failures into module init/exit code::”h]”hŒ;Inject slab allocation failures into module init/exit code:”…””}”(hj-  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MŽhj)  ubjÊ  )”}”(hX–  #!/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 Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait

faulty_system()
{
    bash -c "echo 1 > /proc/self/make-it-fail && exec $*"
}

if [ $# -eq 0 ]
then
    echo "Usage: $0 modulename [ modulename ... ]"
    exit 1
fi

for m in $*
do
    echo inserting $m...
    faulty_system modprobe $m

    echo removing $m...
    faulty_system modprobe -r $m
done”h]”hX–  #!/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 Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait

faulty_system()
{
    bash -c "echo 1 > /proc/self/make-it-fail && exec $*"
}

if [ $# -eq 0 ]
then
    echo "Usage: $0 modulename [ modulename ... ]"
    exit 1
fi

for m in $*
do
    echo inserting $m...
    faulty_system modprobe $m

    echo removing $m...
    faulty_system modprobe -r $m
done”…””•fF      }”hj;  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´Mhj)  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhj&  h²hh³hÊh´Nubah}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´MŽhj  h²hubhŒ
transition”“”)”}”(hŒN------------------------------------------------------------------------------”h]”h}”(h]”h ]”h"]”h$]”h&]”uh1jU  h³hÊh´M¯hj  h²hubhí)”}”(hhh]”hò)”}”(hXg  Inject page allocation failures only for a specific module::

  #!/bin/bash

  FAILTYPE=fail_page_alloc
  module=$1

  if [ -z $module ]
  then
      echo "Usage: $0 <modulename>"
      exit 1
  fi

  modprobe $module

  if [ ! -d /sys/module/$module/sections ]
  then
      echo Module $module is not loaded
      exit 1
  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

  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 Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
  echo Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
  echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth

  trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT

  echo "Injecting errors into the module $module... (interrupt to stop)"
  sleep 1000000
”h]”(hÌ)”}”(hŒ<Inject page allocation failures only for a specific module::”h]”hŒ;Inject page allocation failures only for a specific module:”…””}”(hjh  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M±hjd  ubjÊ  )”}”(hXð  #!/bin/bash

FAILTYPE=fail_page_alloc
module=$1

if [ -z $module ]
then
    echo "Usage: $0 <modulename>"
    exit 1
fi

modprobe $module

if [ ! -d /sys/module/$module/sections ]
then
    echo Module $module is not loaded
    exit 1
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

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 Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
echo Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth

trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT

echo "Injecting errors into the module $module... (interrupt to stop)"
sleep 1000000”h]”hXð  #!/bin/bash

FAILTYPE=fail_page_alloc
module=$1

if [ -z $module ]
then
    echo "Usage: $0 <modulename>"
    exit 1
fi

modprobe $module

if [ ! -d /sys/module/$module/sections ]
then
    echo Module $module is not loaded
    exit 1
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

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 Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait
echo Y > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem
echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth

trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT

echo "Injecting errors into the module $module... (interrupt to stop)"
sleep 1000000”…””}”hjv  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´M³hjd  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhja  h²hh³hÊh´Nubah}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´M±hj  h²hubjV  )”}”(hŒN------------------------------------------------------------------------------”h]”h}”(h]”h ]”h"]”h$]”h&]”uh1jU  h³hÊh´MØhj  h²hubhí)”}”(hhh]”hò)”}”(hX‘  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
  printf %#x -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
      echo "FAILED!"
      umount tmpmnt
  fi

  echo > /sys/kernel/debug/$FAILTYPE/inject

  rmdir tmpmnt
  losetup -d $DEVICE
  rm testfile.img
”h]”(hÌ)”}”(hŒ+Inject open_ctree error while btrfs mount::”h]”hŒ*Inject open_ctree error while btrfs mount:”…””}”(hj¡  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MÚhj  ubjÊ  )”}”(hX+  #!/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
printf %#x -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
    echo "FAILED!"
    umount tmpmnt
fi

echo > /sys/kernel/debug/$FAILTYPE/inject

rmdir tmpmnt
losetup -d $DEVICE
rm testfile.img”h]”hX+  #!/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
printf %#x -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
    echo "FAILED!"
    umount tmpmnt
fi

echo > /sys/kernel/debug/$FAILTYPE/inject

rmdir tmpmnt
losetup -d $DEVICE
rm testfile.img”…””}”hj¯  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´MÜhj  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjš  h²hh³hÊh´Nubah}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´MÚhj  h²hubjV  )”}”(hŒN------------------------------------------------------------------------------”h]”h}”(h]”h ]”h"]”h$]”h&]”uh1jU  h³hÊh´Mþhj  h²hubhí)”}”(hhh]”hò)”}”(hX_  Inject only skbuff allocation failures ::

  # mark skbuff_head_cache as faulty
  echo 1 > /sys/kernel/slab/skbuff_head_cache/failslab
  # Turn on cache filter (off by default)
  echo 1 > /sys/kernel/debug/failslab/cache-filter
  # Turn on fault injection
  echo 1 > /sys/kernel/debug/failslab/times
  echo 1 > /sys/kernel/debug/failslab/probability

”h]”(hÌ)”}”(hŒ)Inject only skbuff allocation failures ::”h]”hŒ&Inject only skbuff allocation failures”…””}”(hjÚ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M hjÖ  ubjÊ  )”}”(hX$  # mark skbuff_head_cache as faulty
echo 1 > /sys/kernel/slab/skbuff_head_cache/failslab
# Turn on cache filter (off by default)
echo 1 > /sys/kernel/debug/failslab/cache-filter
# Turn on fault injection
echo 1 > /sys/kernel/debug/failslab/times
echo 1 > /sys/kernel/debug/failslab/probability”h]”hX$  # mark skbuff_head_cache as faulty
echo 1 > /sys/kernel/slab/skbuff_head_cache/failslab
# Turn on cache filter (off by default)
echo 1 > /sys/kernel/debug/failslab/cache-filter
# Turn on fault injection
echo 1 > /sys/kernel/debug/failslab/times
echo 1 > /sys/kernel/debug/failslab/probability”…””}”hjè  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´MhjÖ  ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hñhjÓ  h²hh³hÊh´Nubah}”(h]”h ]”h"]”h$]”h&]”jÓ  jÔ  uh1hìh³hÊh´M hj  h²hubeh}”(h]”Œapplication-examples”ah ]”h"]”Œapplication examples”ah$]”h&]”uh1hµhh·h²hh³hÊh´MŒubh¶)”}”(hhh]”(h»)”}”(hŒ4Tool to run command with failslab or fail_page_alloc”h]”hŒ4Tool to run command with failslab or fail_page_alloc”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj
  h²hh³hÊh´MubhÌ)”}”(hŒ÷In order to make it easier to accomplish the tasks mentioned above, we can use
tools/testing/fault-injection/failcmd.sh.  Please run a command
"./tools/testing/fault-injection/failcmd.sh --help" for more information and
see the following examples.”h]”hŒûIn order to make it easier to accomplish the tasks mentioned above, we can use
tools/testing/fault-injection/failcmd.sh.  Please run a command
â€œ./tools/testing/fault-injection/failcmd.sh --helpâ€ for more information and
see the following examples.”…””}”(hj  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj
  h²hubhÌ)”}”(hŒ	Examples:”h]”hŒ	Examples:”…””}”(hj)  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj
  h²hubhÌ)”}”(hŒcRun a command "make -C tools/testing/selftests/ run_tests" with injecting slab
allocation failure::”h]”hŒfRun a command â€œmake -C tools/testing/selftests/ run_testsâ€ with injecting slab
allocation failure:”…””}”(hj7  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj
  h²hubjÊ  )”}”(hŒd# ./tools/testing/fault-injection/failcmd.sh \
        -- make -C tools/testing/selftests/ run_tests”h]”hŒd# ./tools/testing/fault-injection/failcmd.sh \
        -- make -C tools/testing/selftests/ run_tests”…””}”hjE  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´Mhj
  h²hubhÌ)”}”(hŒcSame as above except to specify 100 times failures at most instead of one time
at most by default::”h]”hŒbSame as above except to specify 100 times failures at most instead of one time
at most by default:”…””}”(hjS  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Mhj
  h²hubjÊ  )”}”(hŒp# ./tools/testing/fault-injection/failcmd.sh --times=100 \
        -- make -C tools/testing/selftests/ run_tests”h]”hŒp# ./tools/testing/fault-injection/failcmd.sh --times=100 \
        -- make -C tools/testing/selftests/ run_tests”…””}”hja  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´Mhj
  h²hubhÌ)”}”(hŒ[Same as above except to inject page allocation failure instead of slab
allocation failure::”h]”hŒZSame as above except to inject page allocation failure instead of slab
allocation failure:”…””}”(hjo  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M hj
  h²hubjÊ  )”}”(hŒ›# env FAILCMD_TYPE=fail_page_alloc \
        ./tools/testing/fault-injection/failcmd.sh --times=100 \
        -- make -C tools/testing/selftests/ run_tests”h]”hŒ›# env FAILCMD_TYPE=fail_page_alloc \
        ./tools/testing/fault-injection/failcmd.sh --times=100 \
        -- make -C tools/testing/selftests/ run_tests”…””}”hj}  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´M#hj
  h²hubeh}”(h]”Œ4tool-to-run-command-with-failslab-or-fail-page-alloc”ah ]”h"]”Œ4tool to run command with failslab or fail_page_alloc”ah$]”h&]”uh1hµhh·h²hh³hÊh´Mubh¶)”}”(hhh]”(h»)”}”(hŒ Systematic faults using fail-nth”h]”hŒ Systematic faults using fail-nth”…””}”(hj–  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj“  h²hh³hÊh´M(ubhÌ)”}”(hŒrThe following code systematically faults 0-th, 1-st, 2-nd and so on
capabilities in the socketpair() system call::”h]”hŒqThe following code systematically faults 0-th, 1-st, 2-nd and so on
capabilities in the socketpair() system call:”…””}”(hj¤  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´M*hj“  h²hubjÊ  )”}”(hX
  #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];

      system("echo N > /sys/kernel/debug/failslab/ignore-gfp-wait");
      sprintf(buf, "/proc/self/task/%ld/fail-nth", syscall(SYS_gettid));
      fail_nth = open(buf, O_RDWR);
      for (i = 1;; i++) {
              sprintf(buf, "%d", i);
              write(fail_nth, buf, strlen(buf));
              res = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds);
              err = errno;
              pread(fail_nth, buf, sizeof(buf), 0);
              if (res == 0) {
                      close(fds[0]);
                      close(fds[1]);
              }
              printf("%d-th fault %c: res=%d/%d\n", i, atoi(buf) ? 'N' : 'Y',
                      res, err);
              if (atoi(buf))
                      break;
      }
      return 0;
}”h]”hX
  #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];

      system("echo N > /sys/kernel/debug/failslab/ignore-gfp-wait");
      sprintf(buf, "/proc/self/task/%ld/fail-nth", syscall(SYS_gettid));
      fail_nth = open(buf, O_RDWR);
      for (i = 1;; i++) {
              sprintf(buf, "%d", i);
              write(fail_nth, buf, strlen(buf));
              res = socketpair(AF_LOCAL, SOCK_STREAM, 0, fds);
              err = errno;
              pread(fail_nth, buf, sizeof(buf), 0);
              if (res == 0) {
                      close(fds[0]);
                      close(fds[1]);
              }
              printf("%d-th fault %c: res=%d/%d\n", i, atoi(buf) ? 'N' : 'Y',
                      res, err);
              if (atoi(buf))
                      break;
      }
      return 0;
}”…””}”hj²  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´M-hj“  h²hubhÌ)”}”(hŒAn example output::”h]”hŒAn example output:”…””}”(hjÀ  h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´MRhj“  h²hubjÊ  )”}”(hX…  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”h]”hX…  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”…””}”hjÎ  sbah}”(h]”h ]”h"]”h$]”h&]”jÙ  jÚ  uh1jÉ  h³hÊh´MThj“  h²hubeh}”(h]”Œ systematic-faults-using-fail-nth”ah ]”h"]”Œ systematic faults using fail-nth”ah$]”h&]”uh1hµhh·h²hh³hÊh´M(ubeh}”(h]”Œ+fault-injection-capabilities-infrastructure”ah ]”h"]”Œ+fault injection capabilities infrastructure”ah$]”h&]”uh1hµhhh²hh³hÊh´Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”hÊuh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(hºNŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
source_url”NŒtoc_backlinks”Œentry”Œfootnote_backlinks”KŒsectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒstrip_classes”NŒreport_level”KŒ
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