Commit Graph

258 Commits

Author SHA1 Message Date
Linus Torvalds 6f38be8f2c This isn't a hugely busy cycle for documentation, but a few significant
things still showed up:
 
  - A documentation section for ARC processors
  - Reworked and enhanced KUnit documentation
  - The ability to pick your own theme for HTML builds; if the default
    "Read the Docs" theme isn't ugly enough for you, you can now pick
    an uglier one.
  - More Chinese translation work
 
 Plus the usual assortment of fixes and cleanups.
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Merge tag 'docs-5.17' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This isn't a hugely busy cycle for documentation, but a few
  significant things still showed up:

   - A documentation section for ARC processors

   - Reworked and enhanced KUnit documentation

   - The ability to pick your own theme for HTML builds; if the default
     "Read the Docs" theme isn't ugly enough for you, you can now pick
     an uglier one.

   - More Chinese translation work

  Plus the usual assortment of fixes and cleanups"

* tag 'docs-5.17' of git://git.lwn.net/linux: (53 commits)
  scripts: sphinx-pre-install: Fix ctex support on Debian
  docs: discourage use of list tables
  docs: 5.Posting.rst: describe Fixes: and Link: tags
  Documentation: kgdb: Replace deprecated remotebaud
  docs: automarkup.py: Fix invalid HTML link output and broken URI fragments
  Documentation: refer to config RANDOMIZE_BASE for kernel address-space randomization
  Documentation: kgdb: properly capitalize the MAGIC_SYSRQ config
  docs/zh_CN: Update and fix a couple of typos
  scripts: sphinx-pre-install: add required ctex dependency
  Documentation: KUnit: Restyled Frequently Asked Questions
  Documentation: KUnit: Restyle Test Style and Nomenclature page
  Documentation: KUnit: Rework writing page to focus on writing tests
  Documentation: kunit: Reorganize documentation related to running tests
  Documentation: KUnit: Added KUnit Architecture
  Documentation: KUnit: Rewrite getting started
  Documentation: KUnit: Rewrite main page
  docs/zh_CN: Add zh_CN/accounting/delay-accounting.rst
  Documentation/sphinx: fix typos of "its"
  docs/zh_CN: Add sched-domains translation
  doc: fs: remove bdev_try_to_free_page related doc
  ...
2022-01-11 10:00:04 -08:00
Linus Torvalds 1be5bdf8cd KCSAN updates for v5.17
This series provides KCSAN fixes and also the ability to take memory
 barriers into account for weakly-ordered systems.  This last can increase
 the probability of detecting certain types of data races.
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Merge tag 'kcsan.2022.01.09a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull KCSAN updates from Paul McKenney:
 "This provides KCSAN fixes and also the ability to take memory barriers
  into account for weakly-ordered systems. This last can increase the
  probability of detecting certain types of data races"

* tag 'kcsan.2022.01.09a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (29 commits)
  kcsan: Only test clear_bit_unlock_is_negative_byte if arch defines it
  kcsan: Avoid nested contexts reading inconsistent reorder_access
  kcsan: Turn barrier instrumentation into macros
  kcsan: Make barrier tests compatible with lockdep
  kcsan: Support WEAK_MEMORY with Clang where no objtool support exists
  compiler_attributes.h: Add __disable_sanitizer_instrumentation
  objtool, kcsan: Remove memory barrier instrumentation from noinstr
  objtool, kcsan: Add memory barrier instrumentation to whitelist
  sched, kcsan: Enable memory barrier instrumentation
  mm, kcsan: Enable barrier instrumentation
  x86/qspinlock, kcsan: Instrument barrier of pv_queued_spin_unlock()
  x86/barriers, kcsan: Use generic instrumentation for non-smp barriers
  asm-generic/bitops, kcsan: Add instrumentation for barriers
  locking/atomics, kcsan: Add instrumentation for barriers
  locking/barriers, kcsan: Support generic instrumentation
  locking/barriers, kcsan: Add instrumentation for barriers
  kcsan: selftest: Add test case to check memory barrier instrumentation
  kcsan: Ignore GCC 11+ warnings about TSan runtime support
  kcsan: test: Add test cases for memory barrier instrumentation
  kcsan: test: Match reordered or normal accesses
  ...
2022-01-11 09:51:26 -08:00
Christian Löhle 689d8014d9 Documentation: kgdb: Replace deprecated remotebaud
Using set remotebaud to set the baud rate was deprecated in
gdb-7.7 and completely removed from the command parser in gdb-7.8
(released in 2014). Adopt set serial baud instead.

Signed-off-by: Christian Loehle <cloehle@hyperstone.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/4050689967ed46baaa3bfadda53a0e73@hyperstone.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-01-07 09:33:13 -07:00
Lukas Bulwahn e765c747d1 Documentation: kgdb: properly capitalize the MAGIC_SYSRQ config
Most readers are probably going to figure out that the config is actually
all upper-case letters, as all Kconfig symbols are this way.

Properly capitalizing makes the script ./scripts/checkkconfigsymbols.py
happy, which otherwise would report this as a reference to a non-existing
Kconfig symbol.

So, use the right capitalization for the MAGIC_SYSRQ config in the kgdb
documentation.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20211230172423.30430-1-lukas.bulwahn@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-01-03 15:54:00 -07:00
Harinder Singh b36064425a Documentation: KUnit: Restyled Frequently Asked Questions
Reword to align with other chapters.

Signed-off-by: Harinder Singh <sharinder@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-8-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:49:43 -07:00
Harinder Singh 39150e80ed Documentation: KUnit: Restyle Test Style and Nomenclature page
Rewrite page to enhance content consistency.

Signed-off-by: Harinder Singh <sharinder@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-7-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:49:43 -07:00
Harinder Singh 9535743906 Documentation: KUnit: Rework writing page to focus on writing tests
We now have dedicated pages on running tests. Therefore refocus the
usage page on writing tests and add content from tips page and
information on other architectures.

Signed-off-by: Harinder Singh <sharinder@google.com>
Reviewed-by: Tim Bird <tim.bird@sony.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-6-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:49:43 -07:00
Harinder Singh 46201d47d6 Documentation: kunit: Reorganize documentation related to running tests
Consolidate documentation running tests into two pages: "run tests with
kunit_tool" and "run tests without kunit_tool".

Signed-off-by: Harinder Singh <sharinder@google.com>
Reviewed-by: Tim Bird <tim.bird@sony.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-5-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:49:43 -07:00
Harinder Singh bc145b370c Documentation: KUnit: Added KUnit Architecture
Describe the components of KUnit and how the kernel mode parts
interact with kunit_tool.

Signed-off-by: Harinder Singh <sharinder@google.com>
Co-developed-by: Marco Elver <elver@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-4-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:49:06 -07:00
Harinder Singh c48b9ef1f7 Documentation: KUnit: Rewrite getting started
Clarify the purpose of kunit_tool and fixed consistency issues

Signed-off-by: Harinder Singh <sharinder@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-3-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:46:20 -07:00
Harinder Singh 6c6213f4a2 Documentation: KUnit: Rewrite main page
Add a section on advantages of unit testing, how to write unit tests,
KUnit features and Prerequisites.

Signed-off-by: Harinder Singh <sharinder@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20211217044911.798817-2-sharinder@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-23 12:46:20 -07:00
Daniel Latypov 4c2911f1e1 kunit: tool: reconfigure when the used kunitconfig changes
Problem: currently, if you remove something from your kunitconfig,
kunit.py will not regenerate the .config file.
The same thing happens if you did --kunitconfig_add=CONFIG_KASAN=y [1]
and then ran again without it. Your new run will still have KASAN.

The reason is that kunit.py won't regenerate the .config file if it's a
superset of the kunitconfig. This speeds it up a bit for iterating.

This patch adds an additional check that forces kunit.py to regenerate
the .config file if the current kunitconfig doesn't match the previous
one.

What this means:
* deleting entries from .kunitconfig works as one would expect
* dropping  a --kunitconfig_add also triggers a rebuild
* you can still edit .config directly to turn on new options

We implement this by creating a `last_used_kunitconfig` file in the
build directory (so .kunit, by default) after we generate the .config.
When comparing the kconfigs, we compare python sets, so duplicates and
permutations don't trip us up.

The majority of this patch is adding unit tests for the existing logic
and for the new case where `last_used_kunitconfig` differs.

[1] https://lore.kernel.org/linux-kselftest/20211106013058.2621799-2-dlatypov@google.com/

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-12-13 13:59:03 -07:00
Daniel Latypov 58b391d746 Documentation: kunit: remove claims that kunit is a mocking framework
KUnit does not have any first party support for "mocking".

The original RFC had some, but the code got dropped.
However, the documentation patches never got updated. This fixes that.

https://kunit.dev/mocking.html has a current writeup on the status quo
and will hopefully be eventually folded into the in-kernel
Documentation.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-12-13 13:33:42 -07:00
Rae Moar a32fa6b2e8 Documentation: dev-tools: Add KTAP specification
It does not make any significant additions or changes other than those
already in use in the kernel: additional features can be added as they
become necessary and used.

[1]: https://testanything.org/tap-version-13-specification.html

Signed-off-by: Rae Moar <rmoar@google.com>
Co-developed-by: David Gow <davidgow@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20211207190251.18426-1-davidgow@google.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-10 14:37:35 -07:00
Marco Elver 82eb6911d9 kcsan: Document modeling of weak memory
Document how KCSAN models a subset of weak memory and the subset of
missing memory barriers it can detect as a result.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-12-09 16:42:27 -08:00
Linus Torvalds 59a2ceeef6 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...
2021-11-09 10:11:53 -08:00
Sebastian Andrzej Siewior 6f1d34bd49 Documentation/kcov: define `ip' in the example
The example code uses the variable `ip' but never declares it.

Declare `ip' as a 64bit variable which is the same type as the array
from which it loads its value.

Link: https://lkml.kernel.org/r/20210923164741.1859522-3-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-3-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09 10:02:52 -08:00
Sebastian Andrzej Siewior d687a9ccf2 Documentation/kcov: include types.h in the example
Patch series "kcov: PREEMPT_RT fixup + misc", v2.

The last patch in series is follow-up to address the PREEMPT_RT issue
within in kcov reported by Clark [1].  Patches 1-3 are smaller things that
I noticed while staring at it.  Patch 4 is small change which makes
replacement in #5 simpler / more obvious.

[1] https://lkml.kernel.org/r/20210809155909.333073de@theseus.lan

This patch (of 5):

The first example code has includes at the top, the following two
example share that part. The last example (remote coverage collection)
requires the linux/types.h header file due its __aligned_u64 usage.

Add the linux/types.h to the top most example and a comment that the
header files from above are required as it is done in the second
example.

Link: https://lkml.kernel.org/r/20210923164741.1859522-1-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-2-bigeasy@linutronix.de
Link: https://lkml.kernel.org/r/20210923164741.1859522-2-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Clark Williams <williams@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09 10:02:52 -08:00
Linus Torvalds 512b7931ad Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "257 patches.

  Subsystems affected by this patch series: scripts, ocfs2, vfs, and
  mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
  gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
  pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
  memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
  vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
  cleanups, kfence, and damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
  mm/damon: remove return value from before_terminate callback
  mm/damon: fix a few spelling mistakes in comments and a pr_debug message
  mm/damon: simplify stop mechanism
  Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
  Docs/admin-guide/mm/damon/start: simplify the content
  Docs/admin-guide/mm/damon/start: fix a wrong link
  Docs/admin-guide/mm/damon/start: fix wrong example commands
  mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
  mm/damon: remove unnecessary variable initialization
  Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
  mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
  selftests/damon: support watermarks
  mm/damon/dbgfs: support watermarks
  mm/damon/schemes: activate schemes based on a watermarks mechanism
  tools/selftests/damon: update for regions prioritization of schemes
  mm/damon/dbgfs: support prioritization weights
  mm/damon/vaddr,paddr: support pageout prioritization
  mm/damon/schemes: prioritize regions within the quotas
  mm/damon/selftests: support schemes quotas
  mm/damon/dbgfs: support quotas of schemes
  ...
2021-11-06 14:08:17 -07:00
Marco Elver 4f612ed3f7 kfence: default to dynamic branch instead of static keys mode
We have observed that on very large machines with newer CPUs, the static
key/branch switching delay is on the order of milliseconds.  This is due
to the required broadcast IPIs, which simply does not scale well to
hundreds of CPUs (cores).  If done too frequently, this can adversely
affect tail latencies of various workloads.

One workaround is to increase the sample interval to several seconds,
while decreasing sampled allocation coverage, but the problem still
exists and could still increase tail latencies.

As already noted in the Kconfig help text, there are trade-offs: at
lower sample intervals the dynamic branch results in better performance;
however, at very large sample intervals, the static keys mode can result
in better performance -- careful benchmarking is recommended.

Our initial benchmarking showed that with large enough sample intervals
and workloads stressing the allocator, the static keys mode was slightly
better.  Evaluating and observing the possible system-wide side-effects
of the static-key-switching induced broadcast IPIs, however, was a blind
spot (in particular on large machines with 100s of cores).

Therefore, a major downside of the static keys mode is, unfortunately,
that it is hard to predict performance on new system architectures and
topologies, but also making conclusions about performance of new
workloads based on a limited set of benchmarks.

Most distributions will simply select the defaults, while targeting a
large variety of different workloads and system architectures.  As such,
the better default is CONFIG_KFENCE_STATIC_KEYS=n, and re-enabling it is
only recommended after careful evaluation.

For reference, on x86-64 the condition in kfence_alloc() generates
exactly
2 instructions in the kmem_cache_alloc() fast-path:

 | ...
 | cmpl   $0x0,0x1a8021c(%rip)  # ffffffff82d560d0 <kfence_allocation_gate>
 | je     ffffffff812d6003      <kmem_cache_alloc+0x243>
 | ...

which, given kfence_allocation_gate is infrequently modified, should be
well predicted by most CPUs.

Link: https://lkml.kernel.org/r/20211019102524.2807208-2-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:43 -07:00
Marco Elver 5cc906b4b4 kfence: add note to documentation about skipping covered allocations
Add a note briefly mentioning the new policy about "skipping currently
covered allocations if pool close to full." Since this has a notable
impact on KFENCE's bug-detection ability on systems with large uptimes,
it is worth pointing out the feature.

Link: https://lkml.kernel.org/r/20210923104803.2620285-5-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Alexander Potapenko <glider@google.com>
Cc: Aleksandr Nogikh <nogikh@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Taras Madan <tarasmadan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:43 -07:00
Linus Torvalds 624ad333d4 This is a relatively unexciting cycle for documentation.
- Some small scripts/kerneldoc fixes
 
  - More Chinese translation work, but at a much reduced rate.
 
  - The tip-tree maintainer's handbook
 
 ...plus the usual array of build fixes, typo fixes, etc.
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Merge tag 'docs-5.16' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This is a relatively unexciting cycle for documentation.

   - Some small scripts/kerneldoc fixes

   - More Chinese translation work, but at a much reduced rate.

   - The tip-tree maintainer's handbook

  ...plus the usual array of build fixes, typo fixes, etc"

* tag 'docs-5.16' of git://git.lwn.net/linux: (53 commits)
  kernel-doc: support DECLARE_PHY_INTERFACE_MASK()
  docs/zh_CN: add core-api xarray translation
  docs/zh_CN: add core-api assoc_array translation
  speakup: Fix typo in documentation "boo" -> "boot"
  docs: submitting-patches: make section about the Link: tag more explicit
  docs: deprecated.rst: Clarify open-coded arithmetic with literals
  scripts: documentation-file-ref-check: fix bpf selftests path
  scripts: documentation-file-ref-check: ignore hidden files
  coding-style.rst: trivial: fix location of driver model macros
  docs: f2fs: fix text alignment
  docs/zh_CN add PCI pci.rst translation
  docs/zh_CN add PCI index.rst translation
  docs: translations: zh_CN: memory-hotplug.rst: fix a typo
  docs: translations: zn_CN: irq-affinity.rst: add a missing extension
  block: add documentation for inflight
  scripts: kernel-doc: Ignore __alloc_size() attribute
  docs: pdfdocs: Adjust \headheight for fancyhdr
  docs: UML: user_mode_linux_howto_v2 edits
  docs: use the lore redirector everywhere
  docs: proc.rst: mountinfo: align columns
  ...
2021-11-02 22:11:39 -07:00
Linus Torvalds 313b6ffc8e linux-kselftest-kunit-5.16-rc1
This KUnit update for Linux 5.16-rc1 consist of several enhancements
 and fixes:
 
 - ability to run each test suite and test separately
 - support for timing test run
 - several fixes and improvements
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Merge tag 'linux-kselftest-kunit-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull KUnit updates from Shuah Khan:
 "Several enhancements and fixes:

   - ability to run each test suite and test separately

   - support for timing test run

   - several fixes and improvements"

* tag 'linux-kselftest-kunit-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: tool: fix typecheck errors about loading qemu configs
  kunit: tool: continue past invalid utf-8 output
  kunit: Reset suite count after running tests
  kunit: tool: improve compatibility of kunit_parser with KTAP specification
  kunit: tool: yield output from run_kernel in real time
  kunit: tool: support running each suite/test separately
  kunit: tool: actually track how long it took to run tests
  kunit: tool: factor exec + parse steps into a function
  kunit: add 'kunit.action' param to allow listing out tests
  kunit: tool: show list of valid --arch options when invalid
  kunit: tool: misc fixes (unused vars, imports, leaked files)
  kunit: fix too small allocation when using suite-only kunit.filter_glob
  kunit: tool: allow filtering test cases via glob
  kunit: drop assumption in kunit-log-test about current suite
2021-11-02 22:06:20 -07:00
Daniel Latypov a127b154a8 kunit: tool: allow filtering test cases via glob
Commit 1d71307a6f ("kunit: add unit test for filtering suites by
names") introduced the ability to filter which suites we run via glob.

This change extends it so we can also filter individual test cases
inside of suites as well.

This is quite useful when, e.g.
* trying to run just the tests cases you've just added or are working on
* trying to debug issues with test hermeticity

Examples:
$ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit '*exec*.parse*'
...
============================================================
======== [PASSED] kunit_executor_test ========
[PASSED] parse_filter_test
============================================================
Testing complete. 1 tests run. 0 failed. 0 crashed.

$ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit '*.no_matching_tests'
...
[ERROR] no tests run!

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-10-19 14:18:49 -06:00
Vincenzo Frascino 2d27e58514 kasan: Extend KASAN mode kernel parameter
Architectures supported by KASAN_HW_TAGS can provide an asymmetric mode
of execution. On an MTE enabled arm64 hw for example this can be
identified with the asymmetric tagging mode of execution. In particular,
when such a mode is present, the CPU triggers a fault on a tag mismatch
during a load operation and asynchronously updates a register when a tag
mismatch is detected during a store operation.

Extend the KASAN HW execution mode kernel command line parameter to
support asymmetric mode.

Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20211006154751.4463-6-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-07 09:30:24 +01:00
Jonathan Corbet b19511926c Revert "docs: checkpatch: add UNNECESSARY/UNSPECIFIED_INT and UNNECESSARY_ELSE"
This reverts commit cbb817fc2e.

Late-arriving nacks make it clear that I applied this one too soon.

Link: https://lore.kernel.org/lkml/CAKXUXMzEFQd1JJhx4ZbBQiuSB7Fk3bd7dwJYmPOvEtMqZopxpg@mail.gmail.com/
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-10-04 17:13:53 -06:00
Utkarsh Verma 250a0a5ba9 docs: checkpatch: add multiline, do/while, and multiple-assignment messages
Added and documented 3 new message types:
- MULTILINE_DEREFERENCE
- SINGLE_STATEMENT_DO_WHILE_MACRO
- MULTIPLE_ASSIGNMENTS

Signed-off-by: Utkarsh Verma <utkarshverma294@gmail.com>
Link: https://lore.kernel.org/r/20210925163852.12096-1-utkarshverma294@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-27 11:42:45 -06:00
Utkarsh Verma cbb817fc2e docs: checkpatch: add UNNECESSARY/UNSPECIFIED_INT and UNNECESSARY_ELSE
Added and documented 3 new message types:
- UNNECESSARY_INT
- UNSPECIFIED_INT
- UNNECESSARY_ELSE

Signed-off-by: Utkarsh Verma <utkarshverma294@gmail.com>
Link: https://lore.kernel.org/r/20210925201746.15917-1-utkarshverma294@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-27 11:39:16 -06:00
Utkarsh Verma 3454cd5616 Documentation: checkpatch: Add SYMBOLIC_PERMS message
Add a new message type SYMBOLIC_PERMS under the 'Permissions'
subsection. Octal permission bits are easier to read and understand
instead of their symbolic macro names.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Utkarsh Verma <utkarshverma294@gmail.com>
Reviewed-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
Link: https://lore.kernel.org/r/20210904082330.14864-1-utkarshverma294@gmail.com
[jc: Tweaked wording as suggested by Dwaipayan Ray]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-14 15:09:24 -06:00
Utkarsh Verma 29bd0cace2 Documentation: checkpatch: Add TRAILING_SEMICOLON message
Add a new message type TRAILING_SEMICOLON for the macro definitions
that conclude with a semicolon.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Utkarsh Verma <utkarshverma294@gmail.com>
Link: https://lore.kernel.org/r/20210904074201.13532-1-utkarshverma294@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-14 15:07:49 -06:00
Utkarsh Verma d9548979f7 Documentation: checkpatch: Add SPLIT_STRING message
Add a new message type SPLIT_STRING under the 'Indentation and Line
Breaks' subsection. Checkpatch documentation for the splitting of
quoted strings that appear in userspace, across multiple lines.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Utkarsh Verma <utkarshverma294@gmail.com>
Link: https://lore.kernel.org/r/20210904073621.12987-1-utkarshverma294@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-14 15:07:26 -06:00
Linus Torvalds 2d338201d5 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "147 patches, based on 7d2a07b769.

  Subsystems affected by this patch series: mm (memory-hotplug, rmap,
  ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
  alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
  checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
  selftests, ipc, and scripts"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
  scripts: check_extable: fix typo in user error message
  mm/workingset: correct kernel-doc notations
  ipc: replace costly bailout check in sysvipc_find_ipc()
  selftests/memfd: remove unused variable
  Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
  configs: remove the obsolete CONFIG_INPUT_POLLDEV
  prctl: allow to setup brk for et_dyn executables
  pid: cleanup the stale comment mentioning pidmap_init().
  kernel/fork.c: unexport get_{mm,task}_exe_file
  coredump: fix memleak in dump_vma_snapshot()
  fs/coredump.c: log if a core dump is aborted due to changed file permissions
  nilfs2: use refcount_dec_and_lock() to fix potential UAF
  nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
  nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
  nilfs2: fix NULL pointer in nilfs_##name##_attr_release
  nilfs2: fix memory leak in nilfs_sysfs_create_device_group
  trap: cleanup trap_init()
  init: move usermodehelper_enable() to populate_rootfs()
  ...
2021-09-08 12:55:35 -07:00
Marco Elver 4bbf04aa9a kfence: show cpu and timestamp in alloc/free info
Record cpu and timestamp on allocations and frees, and show them in
reports.  Upon an error, this can help correlate earlier messages in the
kernel log via allocation and free timestamps.

Link: https://lkml.kernel.org/r/20210714175312.2947941-1-elver@google.com
Suggested-by: Joern Engel <joern@purestorage.com>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Alexander Potapenko <glider@google.com>
Acked-by: Joern Engel <joern@purestorage.com>
Cc: Yuanyuan Zhong <yzhong@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08 11:50:24 -07:00
Linus Torvalds 14726903c8 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "173 patches.

  Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
  pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
  bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
  hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
  oom-kill, migration, ksm, percpu, vmstat, and madvise)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
  mm/madvise: add MADV_WILLNEED to process_madvise()
  mm/vmstat: remove unneeded return value
  mm/vmstat: simplify the array size calculation
  mm/vmstat: correct some wrong comments
  mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
  selftests: vm: add COW time test for KSM pages
  selftests: vm: add KSM merging time test
  mm: KSM: fix data type
  selftests: vm: add KSM merging across nodes test
  selftests: vm: add KSM zero page merging test
  selftests: vm: add KSM unmerge test
  selftests: vm: add KSM merge test
  mm/migrate: correct kernel-doc notation
  mm: wire up syscall process_mrelease
  mm: introduce process_mrelease system call
  memblock: make memblock_find_in_range method private
  mm/mempolicy.c: use in_task() in mempolicy_slab_node()
  mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
  mm/mempolicy: advertise new MPOL_PREFERRED_MANY
  mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
  ...
2021-09-03 10:08:28 -07:00
Woody Lin c9d1af2b78 mm/kasan: move kasan.fault to mm/kasan/report.c
Move the boot parameter 'kasan.fault' from hw_tags.c to report.c, so it
can support all KASAN modes - generic, and both tag-based.

Link: https://lkml.kernel.org/r/20210713010536.3161822-1-woodylin@google.com
Signed-off-by: Woody Lin <woodylin@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Linus Torvalds aa829778b1 LKMM updates:
- Update documentation and code example
 
 KCSAN updates:
 
  - Introduce CONFIG_KCSAN_STRICT (which RCU uses)
  - Optimize use of get_ctx() by kcsan_found_watchpoint()
  - Rework atomic.h into permissive.h
  - Add the ability to ignore writes that change only one bit of a given data-racy variable.
  - Improve comments
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-debug-2021-09-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull memory model updates from Ingo Molnar:
 "LKMM updates:

   - Update documentation and code example

  KCSAN updates:

   - Introduce CONFIG_KCSAN_STRICT (which RCU uses)

   - Optimize use of get_ctx() by kcsan_found_watchpoint()

   - Rework atomic.h into permissive.h

   - Add the ability to ignore writes that change only one bit of a
     given data-racy variable.

   - Improve comments"

* tag 'locking-debug-2021-09-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/memory-model: Document data_race(READ_ONCE())
  tools/memory-model: Heuristics using data_race() must handle all values
  tools/memory-model: Add example for heuristic lockless reads
  tools/memory-model: Make read_foo_diagnostic() more clearly diagnostic
  kcsan: Make strict mode imply interruptible watchers
  kcsan: permissive: Ignore data-racy 1-bit value changes
  kcsan: Print if strict or non-strict during init
  kcsan: Rework atomic.h into permissive.h
  kcsan: Reduce get_ctx() uses in kcsan_found_watchpoint()
  kcsan: Introduce CONFIG_KCSAN_STRICT
  kcsan: Remove CONFIG_KCSAN_DEBUG
  kcsan: Improve some Kconfig comments
2021-09-02 13:00:15 -07:00
Daniel Latypov 6a499c9c42 kunit: tool: make --raw_output support only showing kunit output
--raw_output is nice, but it would be nicer if could show only output
after KUnit tests have started.

So change the flag to allow specifying a string ('kunit').
Make it so `--raw_output` alone will default to `--raw_output=all` and
have the same original behavior.

Drop the small kunit_parser.raw_output() function since it feels wrong
to put it in "kunit_parser.py" when the point of it is to not parse
anything.

E.g.

$ ./tools/testing/kunit/kunit.py run --raw_output=kunit
...
[15:24:07] Starting KUnit Kernel ...
TAP version 14
1..1
    # Subtest: example
    1..3
    # example_simple_test: initializing
    ok 1 - example_simple_test
    # example_skip_test: initializing
    # example_skip_test: You should not see a line below.
    ok 2 - example_skip_test # SKIP this test should be skipped
    # example_mark_skipped_test: initializing
    # example_mark_skipped_test: You should see a line below.
    # example_mark_skipped_test: You should see this line.
    ok 3 - example_mark_skipped_test # SKIP this test should be skipped
ok 1 - example
[15:24:10] Elapsed time: 6.487s total, 0.001s configuring, 3.510s building, 0.000s running

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-08-13 13:32:01 -06:00
Daniel Latypov 6cb51a1874 kunit: tool: add --kernel_args to allow setting module params
kunit.py currently does not make it possible for users to specify module
parameters (/kernel arguments more generally) unless one directly tweaks
the kunit.py code itself.

This hasn't mattered much so far, but this would make it easier to port
existing tests that expose module parameters over to KUnit and/or let
current KUnit tests take advantage of them.

Tested using an kunit internal parameter:
$ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit \
    --kernel_args=kunit.filter_glob=kunit_status
...
Testing complete. 2 tests run. 0 failed. 0 crashed. 0 skipped.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-08-13 13:28:47 -06:00
Marco Elver 49f72d5358 kcsan: Rework atomic.h into permissive.h
Rework atomic.h into permissive.h to better reflect its purpose, and
introduce kcsan_ignore_address() and kcsan_ignore_data_race().

Introduce CONFIG_KCSAN_PERMISSIVE and update the stub functions in
preparation for subsequent changes.

As before, developers who choose to use KCSAN in "strict" mode will see
all data races and are not affected. Furthermore, by relying on the
value-change filter logic for kcsan_ignore_data_race(), even if the
permissive rules are enabled, the opt-outs in report.c:skip_report()
override them (such as for RCU-related functions by default).

The option CONFIG_KCSAN_PERMISSIVE is disabled by default, so that the
documented default behaviour of KCSAN does not change. Instead, like
CONFIG_KCSAN_IGNORE_ATOMICS, the option needs to be explicitly opted in.

Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20 13:49:43 -07:00
Marco Elver e675d2533a kcsan: Introduce CONFIG_KCSAN_STRICT
Add a simpler Kconfig variable to configure KCSAN's "strict" mode. This
makes it simpler in documentation or messages to suggest just a single
configuration option to select the strictest checking mode (vs.
currently having to list several options).

Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20 13:49:43 -07:00
Daniel Latypov a72fa63043 Documentation: kunit: drop obsolete note about uml_abort for coverage
Commit b6d5799b0b ("kunit: Add 'kunit_shutdown' option") changes KUnit
to call kernel_halt() by default when done testing.

This fixes the issue with not having .gcda files due to not calling
atexit() handlers, and therefore we can stop recommending people
manually tweak UML code.

The need to use older versions of GCC (<=6) remains however, due to
linktime issues, same as before. Note: There also might still be issues
with .gcda files as well in newer versions.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-07-12 13:54:12 -06:00
Linus Torvalds b97efd5e98 Merge branch 'kcsan.2021.05.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull KCSAN updates from Paul McKenney.

* 'kcsan.2021.05.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
  kcsan: Use URL link for pointing access-marking.txt
  kcsan: Document "value changed" line
  kcsan: Report observed value changes
  kcsan: Remove kcsan_report_type
  kcsan: Remove reporting indirection
  kcsan: Refactor access_info initialization
  kcsan: Fold panic() call into print_report()
  kcsan: Refactor passing watchpoint/other_info
  kcsan: Distinguish kcsan_report() calls
  kcsan: Simplify value change detection
  kcsan: Add pointer to access-marking.txt to data_race() bullet
2021-07-04 12:29:16 -07:00
Linus Torvalds a48ad6e7a3 linux-kselftest-kunit-fixes-5.14-rc1
This KUnit update for Linux 5.14-rc1 consists of fixes and features:
 
 -- add support for skipped tests
 -- introduce kunit_kmalloc_array/kunit_kcalloc() helpers
 -- add gnu_printf specifiers
 -- add kunit_shutdown
 -- add unit test for filtering suites by names
 -- convert lib/test_list_sort.c to use KUnit
 -- code organization moving default config to tools/testing/kunit
 -- refactor of internal parser input handling
 -- cleanups and updates to documentation
 -- code cleanup related to casts
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Merge tag 'linux-kselftest-kunit-fixes-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull KUnit update from Shuah Khan:
 "Fixes and features:

   - add support for skipped tests

   - introduce kunit_kmalloc_array/kunit_kcalloc() helpers

   - add gnu_printf specifiers

   - add kunit_shutdown

   - add unit test for filtering suites by names

   - convert lib/test_list_sort.c to use KUnit

   - code organization moving default config to tools/testing/kunit

   - refactor of internal parser input handling

   - cleanups and updates to documentation

   - code cleanup related to casts"

* tag 'linux-kselftest-kunit-fixes-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (29 commits)
  kunit: add unit test for filtering suites by names
  kasan: test: make use of kunit_skip()
  kunit: test: Add example tests which are always skipped
  kunit: tool: Support skipped tests in kunit_tool
  kunit: Support skipped tests
  thunderbolt: test: Reinstate a few casts of bitfields
  kunit: tool: internal refactor of parser input handling
  lib/test: convert lib/test_list_sort.c to use KUnit
  kunit: introduce kunit_kmalloc_array/kunit_kcalloc() helpers
  kunit: Remove the unused all_tests.config
  kunit: Move default config from arch/um -> tools/testing/kunit
  kunit: arch/um/configs: Enable KUNIT_ALL_TESTS by default
  kunit: Add gnu_printf specifiers
  lib/cmdline_kunit: Remove a cast which are no-longer required
  kernel/sysctl-test: Remove some casts which are no-longer required
  thunderbolt: test: Remove some casts which are no longer required
  mmc: sdhci-of-aspeed: Remove some unnecessary casts from KUnit tests
  iio: Remove a cast in iio-test-format which is no longer required
  device property: Remove some casts in property-entry-test
  Documentation: kunit: Clean up some string casts in examples
  ...
2021-07-02 12:58:26 -07:00
Linus Torvalds 65090f30ab Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "191 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
  slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
  mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
  mm,hwpoison: make get_hwpoison_page() call get_any_page()
  mm,hwpoison: send SIGBUS with error virutal address
  mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
  mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
  mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
  mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
  docs: remove description of DISCONTIGMEM
  arch, mm: remove stale mentions of DISCONIGMEM
  mm: remove CONFIG_DISCONTIGMEM
  m68k: remove support for DISCONTIGMEM
  arc: remove support for DISCONTIGMEM
  arc: update comment about HIGHMEM implementation
  alpha: remove DISCONTIGMEM and NUMA
  mm/page_alloc: move free_the_page
  mm/page_alloc: fix counting of managed_pages
  mm/page_alloc: improve memmap_pages dbg msg
  mm: drop SECTION_SHIFT in code comments
  mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
  mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
  mm/page_alloc: scale the number of pages that are batch freed
  ...
2021-06-29 17:29:11 -07:00
David Gow 3ff16d30f5 kasan: test: improve failure message in KUNIT_EXPECT_KASAN_FAIL()
The KUNIT_EXPECT_KASAN_FAIL() macro currently uses KUNIT_EXPECT_EQ() to
compare fail_data.report_expected and fail_data.report_found.  This always
gave a somewhat useless error message on failure, but the addition of
extra compile-time checking with READ_ONCE() has caused it to get much
longer, and be truncated before anything useful is displayed.

Instead, just check fail_data.report_found by hand (we've just set
report_expected to 'true'), and print a better failure message with
KUNIT_FAIL().  Because of this, report_expected is no longer used
anywhere, and can be removed.

Beforehand, a failure in:
KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)area)[3100]);
would have looked like:
[22:00:34] [FAILED] vmalloc_oob
[22:00:34]     # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:991
[22:00:34]     Expected ({ do { extern void __compiletime_assert_705(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(fail_data.report_expected) == sizeof(char) || sizeof(fail_data.repp
[22:00:34]     not ok 45 - vmalloc_oob

With this change, it instead looks like:
[22:04:04] [FAILED] vmalloc_oob
[22:04:04]     # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:993
[22:04:04]     KASAN failure expected in "((volatile char *)area)[3100]", but none occurred
[22:04:04]     not ok 45 - vmalloc_oob

Also update the example failure in the documentation to reflect this.

Link: https://lkml.kernel.org/r/20210606005531.165954-1-davidgow@google.com
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: David Gow <davidgow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:52 -07:00
David Gow d9d6b8225e kunit: Move default config from arch/um -> tools/testing/kunit
The default .kunitconfig file is currently kept in
arch/um/configs/kunit_defconfig, but -- with the impending QEMU patch
-- will no-longer be exclusively used for UML-based kernels.

Move it alongside the other KUnit configs in
tools/testing/kunit/configs, and give it a name which matches the
existing all_tests.config and broken_on_uml.config files.

Also update the Getting Started documentation to point to the new file.

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-06-23 17:49:17 -06:00
David Gow 99a8e899fa Documentation: kunit: Clean up some string casts in examples
As the type checking is no longer excessively strict, get rid of the
unsightly (char*) casts -- and comment discussing them -- from the KUnit
usage page.

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-06-23 16:36:29 -06:00
Mauro Carvalho Chehab 2ec73ece4e docs: dev-tools: kunit: don't use a table for docs name
We'll be replacing :doc:`foo` references to
Documentation/foo.rst. Yet, here it happens inside a table.
Doing a search-and-replace would break it.

Yet, as there's no good reason to use a table there,
let's just convert it into a list.

Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-06-23 14:19:19 -06:00
Mauro Carvalho Chehab 654a5bd0ea docs: dev-tools: kunit: avoid using ReST :doc:`foo` markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6fde409079959a95b62b9b2692503608d7ff0dbd.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:37 -06:00
Mauro Carvalho Chehab 3a8b57d27a docs: dev-tools: testing-overview.rst: avoid using ReST :doc:`foo` markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6bbecd4170ee08f36f8060b0719a46c64a21aefc.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:37 -06:00