The root document usually has a special :ref:`genindex` link to the
generated index. This is also the case for Documentation/index.rst. The
other index.rst files deeper in the directory hierarchy usually don't.
For SPHINXDIRS builds, the root document isn't Documentation/index.rst,
but some other index.rst in the hierarchy. Currently they have a
".. only::" block to add the index link when doing SPHINXDIRS html
builds.
This is obviously very tedious and repetitive. The link is also added to
all index.rst files in the hierarchy for SPHINXDIRS builds, not just the
root document.
Put the boilerplate in a sphinx-includes/subproject-index.rst file, and
include it at the end of the root document for subproject builds in an
ad-hoc source-read extension defined in conf.py.
For now, keep having the boilerplate in translations, because this
approach currently doesn't cover translated index link headers.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[jc: did s/doctree/kern_doc_dir/ ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260123143149.2024303-1-jani.nikula@intel.com>
Introduce a fault injection mechanism to force skb reallocation. The
primary goal is to catch bugs related to pointer invalidation after
potential skb reallocation.
The fault injection mechanism aims to identify scenarios where callers
retain pointers to various headers in the skb but fail to reload these
pointers after calling a function that may reallocate the data. This
type of bug can lead to memory corruption or crashes if the old,
now-invalid pointers are used.
By forcing reallocation through fault injection, we can stress-test code
paths and ensure proper pointer management after potential skb
reallocations.
Add a hook for fault injection in the following functions:
* pskb_trim_rcsum()
* pskb_may_pull_reason()
* pskb_trim()
As the other fault injection mechanism, protect it under a debug Kconfig
called CONFIG_FAIL_SKB_REALLOC.
This patch was *heavily* inspired by Jakub's proposal from:
https://lore.kernel.org/all/20240719174140.47a868e6@kernel.org/
CC: Akinobu Mita <akinobu.mita@gmail.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Guillaume Nault <gnault@redhat.com>
Link: https://patch.msgid.link/20241107-fault_v6-v6-1-1b82cb6ecacd@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The failslab fault injection mechanism has an undocumented capability
that provides significant utility in testing and debugging. This feature,
introduced in commit 4c13dd3b48 ("failslab: add ability to filter slab
caches"), allows for targeted error injection into specific slab caches.
However, it was inadvertently left undocumented at the time of its
implementation.
Add documentation for the cache-filter feature in the failslab mode
description. Also, providing a practical example demonstrating how to
use cache-filter to inject failures specifically when allocating socket
buffers (skbs).
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240726120930.3231333-1-leitao@debian.org
Function ll_rw_block was removed in commit 79f5978420 ("fs/buffer:
remove ll_rw_block() helper"). There is no unified function to sumbit
read or write buffer in block layer for now. Consider similar sematics,
we can choose submit_bh() to replace ll_rw_block() as predefined crash
point. In submit_bh(), it also takes read or write flag as the first
argument and invoke submit_bio() to submit I/O request to block layer.
Fixes: 79f5978420 ("fs/buffer: remove ll_rw_block() helper")
Signed-off-by: Yue Zhao <findns94@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230503162944.3969-1-findns94@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The null_blk driver has multiple driver-specific fault injection
mechanisms. Each fault injection configuration can only be specified by a
module parameter and cannot be reconfigured without reloading the driver.
Also, each configuration is common to all devices and is initialized every
time a new device is added.
This change adds the following subdirectories for each null_blk device.
/sys/kernel/config/nullb/<disk>/timeout_inject
/sys/kernel/config/nullb/<disk>/requeue_inject
/sys/kernel/config/nullb/<disk>/init_hctx_fault_inject
Each fault injection attribute can be dynamically set per device by a
corresponding file in these directories.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Link: https://lore.kernel.org/r/20230327143733.14599-3-akinobu.mita@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ignore-gfp-wait and ignore-gfp-highmem defaults are actually true (Y) in
both failslab and fail_page_alloc, not false as the docs suggest. See
page_alloc.c:3762 and failslab.c:13
At the same time use 'Y' instead of '1' in the example scripts just for
consistency. (though 1 would work)
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull char / misc driver updates from Greg KH:
"Here is the big set of char/misc driver changes for 5.15-rc1.
Lots of different driver subsystems are being updated in here,
notably:
- mhi subsystem update
- fpga subsystem update
- coresight/hwtracing subsystem update
- interconnect subsystem update
- nvmem subsystem update
- parport drivers update
- phy subsystem update
- soundwire subsystem update
and there are some other char/misc drivers being updated as well:
- binder driver additions
- new misc drivers
- lkdtm driver updates
- mei driver updates
- sram driver updates
- other minor driver updates.
Note, there are no habanalabs driver updates in this pull request,
that will probably come later before -rc1 is out in a different
request.
All of these have been in linux-next for a while with no reported
problems"
* tag 'char-misc-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (169 commits)
Revert "bus: mhi: Add inbound buffers allocation flag"
misc/pvpanic: fix set driver data
VMCI: fix NULL pointer dereference when unmapping queue pair
char: mware: fix returnvar.cocci warnings
parport: remove non-zero check on count
soundwire: cadence: do not extend reset delay
soundwire: intel: conditionally exit clock stop mode on system suspend
soundwire: intel: skip suspend/resume/wake when link was not started
soundwire: intel: fix potential race condition during power down
phy: qcom-qmp: Add support for SM6115 UFS phy
dt-bindings: phy: qcom,qmp: Add SM6115 UFS PHY bindings
phy: qmp: Provide unique clock names for DP clocks
lkdtm: remove IDE_CORE_CP crashpoint
lkdtm: replace SCSI_DISPATCH_CMD with SCSI_QUEUE_RQ
coresight: Replace deprecated CPU-hotplug functions.
Documentation: coresight: Add documentation for CoreSight config
coresight: syscfg: Add initial configfs support
coresight: config: Add preloaded configurations
coresight: etm4x: Add complex configuration handlers to etmv4
coresight: etm-perf: Update to activate selected configuration
...
When scsi_dispatch_cmd was moved to scsi_lib.c and made static, some
compilers (i.e., at least gcc 8.4.0) decided to compile this
inline. This is a problem for lkdtm.ko, which inserted a kprobe
on this function for the SCSI_DISPATCH_CMD crashpoint.
Move this crashpoint one function up the call chain to
scsi_queue_rq. Though this is also a static function, it should never be
inlined because it is assigned as a structure entry. Therefore,
kprobe_register should always be able to find it.
Fixes: 82042a2cdb ("scsi: move scsi_dispatch_cmd to scsi_lib.c")
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kevin Mitchell <kevmitch@arista.com>
Link: https://lore.kernel.org/r/20210819022940.561875-2-kevmitch@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fault injection uses debugfs in a way that the provided values via sysfs
are interpreted as u64. Providing negative numbers results in an error:
/sys/kernel/debug/fail_function# echo -1 > times
sh: write error: Invalid argument
Update the docs and examples to use "printf %#x <val>" in these cases.
For "retval", reword the paragraph a little and fix a typo.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210603125841.27436-1-wsa+renesas@sang-engineering.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull documentation fixes from Jonathan Corbet:
"A handful of late-arriving documentation fixes"
* tag 'docs-5.10-2' of git://git.lwn.net/linux:
docs: Add two missing entries in vm sysctl index
docs/vm: trivial fixes to several spelling mistakes
docs: submitting-patches: describe preserving review/test tags
Documentation: Chinese translation of Documentation/arm64/hugetlbpage.rst
Documentation: x86: fix a missing word in x86_64/mm.rst.
docs: driver-api: remove a duplicated index entry
docs: lkdtm: Modernize and improve details
docs: deprecated.rst: Expand str*cpy() replacement notes
docs/cpu-load: format the example code.
Patch series "add fault injection to user memory access", v3.
The goal of this series is to improve testing of fault-tolerance in usages
of user memory access functions, by adding support for fault injection.
syzkaller/syzbot are using the existing fault injection modes and will use
this particular feature also.
The first patch adds failure injection capability for usercopy functions.
The second changes usercopy functions to use this new failure capability
(copy_from_user, ...). The third patch adds get/put/clear_user failures
to x86.
This patch (of 3):
Add a failure injection capability to improve testing of fault-tolerance
in usages of user memory access functions.
Add CONFIG_FAULT_INJECTION_USERCOPY to enable faults in usercopy
functions. The should_fail_usercopy function is to be called by these
functions (copy_from_user, get_user, ...) in order to fail or not.
Signed-off-by: Albert van der Linde <alinde@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20200831171733.955393-1-alinde@google.com
Link: http://lkml.kernel.org/r/20200831171733.955393-2-alinde@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nvme_end_request is a bit misnamed, as it wraps around the
blk_mq_complete_* API. It's semantics also are non-trivial, so give it
a more descriptive name and add a comment explaining the semantics.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The contents of those directories were orphaned at the documentation
body.
While those directories could likely be moved to be inside some guide,
I'm opting to just adding their indexes to the main one, removing the
:orphan: and adding the SPDX header.
For the drivers, the rationale is that the documentation contains
a mix of Kernelspace, uAPI and admin-guide. So, better to keep them on
separate directories, as we've be doing with similar subsystem-specific
docs that were not split yet.
For the others, well... I'm too lazy to do the move. Also, it
seems to make sense to keep at least some of those at the main
dir (like kbuild, for example). In any case, a latter patch
could do the move.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
