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2021-07-04Merge branch 'kcsan.2021.05.18a' of ↵Linus Torvalds
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
2021-07-02Merge tag 'linux-kselftest-kunit-fixes-5.14-rc1' of ↵Linus Torvalds
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 ...
2021-06-29Merge branch 'akpm' (patches from Andrew)Linus Torvalds
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 ...
2021-06-29kasan: test: improve failure message in KUNIT_EXPECT_KASAN_FAIL()David Gow
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>
2021-06-23kunit: Move default config from arch/um -> tools/testing/kunitDavid Gow
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>
2021-06-23Documentation: kunit: Clean up some string casts in examplesDavid Gow
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>
2021-06-23docs: dev-tools: kunit: don't use a table for docs nameMauro Carvalho Chehab
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>
2021-06-17docs: dev-tools: kunit: avoid using ReST :doc:`foo` markupMauro Carvalho Chehab
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>
2021-06-17docs: dev-tools: testing-overview.rst: avoid using ReST :doc:`foo` markupMauro Carvalho Chehab
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>
2021-06-17docs: dev-tools: kunit: don't use a table for docs nameMauro Carvalho Chehab
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> Link: https://lore.kernel.org/r/07d3a8ccafbb6345d6e78fb090290859e84361a1.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-14docs: checkpatch: Document and segregate more checkpatch message typesDwaipayan Ray
Add and document more checkpatch message types. About 50% of all message types are documented now. In addition to this: - Create a new subsection 'Indentation and Line Breaks'. - Rename subsection 'Comment style' to simply 'Comments'. - Refactor some of the existing types to appropriate subsections. Reviewed-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Tested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com> Link: https://lore.kernel.org/r/20210614141132.6881-1-dwaipayanray1@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-11Documentation: kunit: document support for QEMU in kunit_toolBrendan Higgins
Document QEMU support, what it does, and how to use it in kunit_tool. Signed-off-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-05-21Documentation: kunit: Update kunit_tool pageDavid Gow
The kunit_tool documentation page was pretty minimal, and a bit outdated. Update it and flesh it out a bit. In particular, - Mention that .kunitconfig is now in the build directory - Describe the use of --kunitconfig to specify a different config framgent - Mention the split functionality (i.e., commands other than 'run') - Describe --raw_output and kunit.py parse - Mention the globbing support - Provide a quick overview of other options, including --build_dir and --alltests Note that this does overlap a little with the new running_tips page. I don't think it's a problem having both: this page is supposed to be a bit more of a reference, rather than a list of useful tips, so the fact that they both describe the same features isn't a problem. Signed-off-by: David Gow <davidgow@google.com> Reviewed-by: Daniel Latypov <dlatypov@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-05-21Documentation: kunit: add tips for running KUnitDaniel Latypov
This is long overdue. There are several things that aren't nailed down (in-tree .kunitconfig's), or partially broken (GCOV on UML), but having them documented, warts and all, is better than having nothing. This covers a bunch of the more recent features * kunit_filter_glob * kunit.py run --kunitconfig * slightly more detail on building tests as modules * CONFIG_KUNIT_DEBUGFS By my count, the only headline features now not mentioned are the KASAN integration and KernelCI json output support (kunit.py run --json). And then it also discusses how to get code coverage reports under UML and non-UML since this is a question people have repeatedly asked. Non-UML coverage collection is no different from normal, but we should probably explicitly call this out. As for UML, I was able to get it working again with two small hacks.* E.g. with CONFIG_KUNIT=y && CONFIG_KUNIT_ALL_TESTS=y Overall coverage rate: lines......: 15.1% (18294 of 120776 lines) functions..: 16.8% (1860 of 11050 functions) Note: this doesn't document --alltests since this is not stable yet. Hopefully being run more frequently as part of KernelCI will help... *Using gcc/gcov-6 and not using uml_abort() in os_dump_core(). I've documented these hacks in "Notes" but left TODOs for brendanhiggins@google.com who tracked down the runtime issue in GCC. To be clear: these are not issues specific to KUnit, but rather to UML. 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>
2021-05-20Documentation: checkpatch: Tweak BIT() macro includeAndrew Jeffery
While include/linux/bitops.h brings in the BIT() macro, it was moved to include/linux/bits.h in commit 8bd9cb51daac ("locking/atomics, asm-generic: Move some macros from <linux/bitops.h> to a new <linux/bits.h> file"). Since that commit BIT() has moved again into include/vdso/bits.h via commit 3945ff37d2f4 ("linux/bits.h: Extract common header for vDSO"). I think the move to the vDSO header can be considered an implementation detail, so for now update the checkpatch documentation to recommend use of include/linux/bits.h. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Acked-by: Jiri Slaby <jirislaby@kernel.org> Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Acked-by: Dwaipayan Ray <dwaipayanray1@gmail.com> Cc: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20210520093949.511471-1-andrew@aj.id.au Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-20docs: Add more message type documentations for checkpatchDwaipayan Ray
- Document a couple of more checkpatch message types. - Add a blank line before all `See:` lines to improve the rst output. - Create a new subsection `Permissions` and move a few types to it. Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com> Acked-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Link: https://lore.kernel.org/r/20210515132348.19082-1-dwaipayanray1@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-18kcsan: Use URL link for pointing access-marking.txtAkira Yokosawa
For consistency within kcsan.rst, use a URL link as the same as in section "Data Races". Acked-by: Marco Elver <elver@google.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-18kcsan: Document "value changed" lineMarco Elver
Update the example reports based on the latest reports generated by kcsan_test module, which now include the "value changed" line. Add a brief description of the "value changed" line. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-18kcsan: Add pointer to access-marking.txt to data_race() bulletPaul E. McKenney
This commit references tools/memory-model/Documentation/access-marking.txt in the bullet introducing data_race(). The access-marking.txt file gives advice on when data_race() should and should not be used. Suggested-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-07scripts/gdb: add lx_current support for arm64Barry Song
arm64 uses SP_EL0 to save the current task_struct address. While running in EL0, SP_EL0 is clobbered by userspace. So if the upper bit is not 1 (not TTBR1), the current address is invalid. This patch checks the upper bit of SP_EL0, if the upper bit is 1, lx_current() of arm64 will return the derefrence of current task. Otherwise, lx_current() will tell users they are running in userspace(EL0). While arm64 is running in EL0, it is actually pointless to print current task as the memory of kernel space is not accessible in EL0. Link: https://lkml.kernel.org/r/20210314203444.15188-3-song.bao.hua@hisilicon.com Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kieran Bingham <kbingham@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07scripts/gdb: document lx_current is only supported by x86Barry Song
Patch series "scripts/gdb: clarify the platforms supporting lx_current and add arm64 support", v2. lx_current depends on per_cpu current_task variable which exists on x86 only. so it actually works on x86 only. the 1st patch documents this clearly; the 2nd patch adds support for arm64. This patch (of 2): x86 is the only architecture which has per_cpu current_task: arch$ git grep current_task | grep -i per_cpu x86/include/asm/current.h:DECLARE_PER_CPU(struct task_struct *, current_task); x86/kernel/cpu/common.c:DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned = x86/kernel/cpu/common.c:EXPORT_PER_CPU_SYMBOL(current_task); x86/kernel/cpu/common.c:DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task; x86/kernel/cpu/common.c:EXPORT_PER_CPU_SYMBOL(current_task); x86/kernel/smpboot.c: per_cpu(current_task, cpu) = idle; On other architectures, lx_current() will lead to a python exception: (gdb) p $lx_current().pid Python Exception <class 'gdb.error'> No symbol "current_task" in current context.: Error occurred in Python: No symbol "current_task" in current context. To avoid more people struggling and wasting time in other architectures, document it. Link: https://lkml.kernel.org/r/20210314203444.15188-1-song.bao.hua@hisilicon.com Link: https://lkml.kernel.org/r/20210314203444.15188-2-song.bao.hua@hisilicon.com Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Kieran Bingham <kbingham@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update tests sectionAndrey Konovalov
Update the "Tests" section in KASAN documentation: - Add an introductory sentence. - Add proper indentation for the list of ways to run KUnit tests. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/fb08845e25c8847ffda271fa19cda2621c04a65b.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update ignoring accesses sectionAndrey Konovalov
Update the "Ignoring accesses" section in KASAN documentation: - Mention __no_sanitize_address/noinstr. - Mention kasan_disable/enable_current(). - Mention kasan_reset_tag()/page_kasan_tag_reset(). - Readability and punctuation clean-ups. Link: https://lkml.kernel.org/r/4531ba5f3eca61f6aade863c136778cc8c807a64.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update shadow memory sectionAndrey Konovalov
Update the "Shadow memory" section in KASAN documentation: - Rearrange the introduction paragraph do it doesn't give a "KASAN has an issue" impression. - Update the list of architectures with vmalloc support. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/00f8c38b0fd5290a3f4dced04eaba41383e67e14.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update HW_TAGS implementation details sectionAndrey Konovalov
Update the "Implementation details" section for HW_TAGS KASAN: - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/ee2caf4c138cc1fd239822c2abefd5af6c057744.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update SW_TAGS implementation details sectionAndrey Konovalov
Update the "Implementation details" section for SW_TAGS KASAN: - Clarify the introduction sentence. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/69b9b2e49d8cf789358fa24558be3fc0ce4ee32c.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update GENERIC implementation details sectionAndrey Konovalov
Update the "Implementation details" section for generic KASAN: - Don't mention kmemcheck, it's not present in the kernel anymore. - Don't mention GCC as the only supported compiler. - Update kasan_mem_to_shadow() definition to match actual code. - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/f2f35fdab701f8c709f63d328f98aec2982c8acc.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update boot parameters sectionAndrey Konovalov
Update the "Boot parameters" section in KASAN documentation: - Mention panic_on_warn. - Mention kasan_multi_shot and its interaction with panic_on_warn. - Clarify kasan.fault=panic interaction with panic_on_warn. - A readability clean-up. Link: https://lkml.kernel.org/r/01364952f15789948f0627d6733b5cdf5209f83a.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update error reports sectionAndrey Konovalov
Update the "Error reports" section in KASAN documentation: - Mention that bug titles are best-effort. - Move and reword the part about auxiliary stacks from "Implementation details". - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/3531e8fe6972cf39d1954e3643237b19eb21227e.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update usage sectionAndrey Konovalov
Update the "Usage" section in KASAN documentation: - Add inline code snippet markers. - Reword the part about stack traces for clarity. - Other minor clean-ups. Link: https://lkml.kernel.org/r/48427809cd4b8b5d6bc00926cbe87e2b5081df17.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: update overview sectionAndrey Konovalov
Update the "Overview" section in KASAN documentation: - Outline main use cases for each mode. - Mention that HW_TAGS mode need compiler support too. - Move the part about SLUB/SLAB support from "Usage" to "Overview". - Punctuation, readability, and other minor clean-ups. Link: https://lkml.kernel.org/r/1486fba8514de3d7db2f47df2192db59228b0a7b.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30kasan: docs: clean up sectionsAndrey Konovalov
Update KASAN documentation: - Give some sections clearer names. - Remove unneeded subsections in the "Tests" section. - Move the "For developers" section and split into subsections. Link: https://lkml.kernel.org/r/c2bbb56eaea80ad484f0ee85bb71959a3a63f1d7.1615559068.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-28Merge tag 'locking-core-2021-04-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: - rtmutex cleanup & spring cleaning pass that removes ~400 lines of code - Futex simplifications & cleanups - Add debugging to the CSD code, to help track down a tenacious race (or hw problem) - Add lockdep_assert_not_held(), to allow code to require a lock to not be held, and propagate this into the ath10k driver - Misc LKMM documentation updates - Misc KCSAN updates: cleanups & documentation updates - Misc fixes and cleanups - Fix locktorture bugs with ww_mutexes * tag 'locking-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) kcsan: Fix printk format string static_call: Relax static_call_update() function argument type static_call: Fix unused variable warn w/o MODULE locking/rtmutex: Clean up signal handling in __rt_mutex_slowlock() locking/rtmutex: Restrict the trylock WARN_ON() to debug locking/rtmutex: Fix misleading comment in rt_mutex_postunlock() locking/rtmutex: Consolidate the fast/slowpath invocation locking/rtmutex: Make text section and inlining consistent locking/rtmutex: Move debug functions as inlines into common header locking/rtmutex: Decrapify __rt_mutex_init() locking/rtmutex: Remove pointless CONFIG_RT_MUTEXES=n stubs locking/rtmutex: Inline chainwalk depth check locking/rtmutex: Move rt_mutex_debug_task_free() to rtmutex.c locking/rtmutex: Remove empty and unused debug stubs locking/rtmutex: Consolidate rt_mutex_init() locking/rtmutex: Remove output from deadlock detector locking/rtmutex: Remove rtmutex deadlock tester leftovers locking/rtmutex: Remove rt_mutex_timed_lock() MAINTAINERS: Add myself as futex reviewer locking/mutex: Remove repeated declaration ...
2021-04-27Merge tag 'linux-kselftest-kunit-5.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull KUnit updates from Shuah Khan: "Several fixes and a new feature to support failure from dynamic analysis tools such as UBSAN and fake ops for testing. - a fake ops struct for testing a "free" function to complain if it was called with an invalid argument, or caught a double-free. Most return void and have no normal means of signalling failure (e.g. super_operations, iommu_ops, etc.)" * tag 'linux-kselftest-kunit-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: Documentation: kunit: add tips for using current->kunit_test kunit: fix -Wunused-function warning for __kunit_fail_current_test kunit: support failure from dynamic analysis tools kunit: tool: make --kunitconfig accept dirs, add lib/kunit fragment kunit: make KUNIT_EXPECT_STREQ() quote values, don't print literals kunit: Match parenthesis alignment to improve code readability
2021-04-27Merge tag 'linux-kselftest-next-5.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest updates from Shuah Khan: - fixes and updates to resctrl test from Fenghua Yu and Reinette Chatre - fixes to Kselftest documentation, framework - minor spelling correction in timers test * tag 'linux-kselftest-next-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits) selftests/resctrl: Change a few printed messages Documentation: kselftest: fix path to test module files selftests/resctrl: Create .gitignore to include resctrl_tests selftests/resctrl: Fix checking for < 0 for unsigned values selftests/resctrl: Fix incorrect parsing of iMC counters selftests/resctrl: Fix unmount resctrl FS selftests/resctrl: Skip the test if requested resctrl feature is not supported selftests/resctrl: Modularize resctrl test suite main() function selftests/resctrl: Don't hard code value of "no_of_bits" variable selftests/resctrl: Fix MBA/MBM results reporting format selftests/resctrl: Use resctrl/info for feature detection selftests/resctrl: Check for resctrl mount point only if resctrl FS is supported selftests/resctrl: Add config dependencies selftests/resctrl: Fix a printed message selftests/resctrl: Share show_cache_info() by CAT and CMT tests selftests/resctrl: Call kselftest APIs to log test results selftests/resctrl: Rename CQM test as CMT test selftests/resctrl: Fix missing options "-n" and "-p" selftests/resctrl: Ensure sibling CPU is not same as original CPU selftests/resctrl: Clean up resctrl features check ...
2021-04-26Merge tag 'docs-5.13' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It's been a relatively busy cycle in docsland, though more than usually well contained to Documentation/ itself. Highlights include: - The Chinese translators have been busy and show no signs of stopping anytime soon. Italian has also caught up. - Aditya Srivastava has been working on improvements to the kernel-doc script. - Thorsten continues his work on reporting-issues.rst and related documentation around regression reporting. - Lots of documentation updates, typo fixes, etc. as usual" * tag 'docs-5.13' of git://git.lwn.net/linux: (139 commits) docs/zh_CN: add openrisc translation to zh_CN index docs/zh_CN: add openrisc index.rst translation docs/zh_CN: add openrisc todo.rst translation docs/zh_CN: add openrisc openrisc_port.rst translation docs/zh_CN: add core api translation to zh_CN index docs/zh_CN: add core-api index.rst translation docs/zh_CN: add core-api irq index.rst translation docs/zh_CN: add core-api irq irqflags-tracing.rst translation docs/zh_CN: add core-api irq irq-domain.rst translation docs/zh_CN: add core-api irq irq-affinity.rst translation docs/zh_CN: add core-api irq concepts.rst translation docs: sphinx-pre-install: don't barf on beta Sphinx releases scripts: kernel-doc: improve parsing for kernel-doc comments syntax docs/zh_CN: two minor fixes in zh_CN/doc-guide/ Documentation: dev-tools: Add Testing Overview docs/zh_CN: add translations in zh_CN/dev-tools/gcov docs: reporting-issues: make people CC the regressions list MAINTAINERS: add regressions mailing list doc:it_IT: align Italian documentation docs/zh_CN: sync reporting-issues.rst ...
2021-04-15Documentation: dev-tools: Add Testing OverviewDavid Gow
The kernel now has a number of testing and debugging tools, and we've seen a bit of confusion about what the differences between them are. Add a basic documentation outlining the testing tools, when to use each, and how they interact. This is a pretty quick overview rather than the idealised "kernel testing guide" that'd probably be optimal, but given the number of times questions like "When do you use KUnit and when do you use Kselftest?" are being asked, it seemed worth at least having something. Hopefully this can form the basis for more detailed documentation later. Signed-off-by: David Gow <davidgow@google.com> Reviewed-by: Marco Elver <elver@google.com> Reviewed-by: Daniel Latypov <dlatypov@google.com> Link: https://lore.kernel.org/r/20210415054036.581117-1-davidgow@google.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-11kasan: Add KASAN mode kernel parameterVincenzo Frascino
Architectures supported by KASAN_HW_TAGS can provide a sync or async mode of execution. On an MTE enabled arm64 hw for example this can be identified with the synchronous or asynchronous tagging mode of execution. In synchronous mode, an exception is triggered if a tag check fault occurs. In asynchronous mode, if a tag check fault occurs, the TFSR_EL1 register is updated asynchronously. The kernel checks the corresponding bits periodically. KASAN requires a specific kernel command line parameter to make use of this hw features. Add KASAN HW execution mode kernel command line parameter. Note: This patch adds the kasan.mode kernel parameter and the sync/async kernel command line options to enable the described features. [ Add a new var instead of exposing kasan_arg_mode to be consistent with flags for other command line arguments. ] Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Link: https://lore.kernel.org/r/20210315132019.33202-3-vincenzo.frascino@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-04-08docs/gcov: Convert two tags to ref in dev-tools/gov.rstWu XiangCheng
Htmldocs does not display the chapter number, convert the two manual chapter number tags to ref tags. Signed-off-by: Wu XiangCheng <bobwxc@email.cn> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Link: https://lore.kernel.org/r/20210403113752.GA32236@mipc Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-07Documentation: kunit: add tips for using current->kunit_testDaniel Latypov
As of commit 359a376081d4 ("kunit: support failure from dynamic analysis tools"), we can use current->kunit_test to find the current kunit test. Mention this in tips.rst and give an example of how this can be used in conjunction with `test->priv` to pass around state and specifically implement something like mocking. There's a lot more we could go into on that topic, but given that example is already longer than every other "tip" on this page, we just point to the API docs and leave filling in the blanks as an exercise to the reader. Also give an example of kunit_fail_current_test(). Signed-off-by: Daniel Latypov <dlatypov@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-04-02Documentation: kselftest: fix path to test module filesAntonio Terceiro
The top-level kselftest directory is not called kselftest, but selftests. Signed-off-by: Antonio Terceiro <antonio.terceiro@linaro.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-03-25docs: document all error message types in checkpatchDwaipayan Ray
All the error message types now have a verbose description. Also there are two new groups of message types: - Macros, Attributes and Symbols - Functions and Variables Rearrange the message types to fit these new groups as needed. Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com> Reviewed-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Link: https://lore.kernel.org/r/20210322082139.33822-1-dwaipayanray1@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-08kcsan: Add missing license and copyright headersMarco Elver
Adds missing license and/or copyright headers for KCSAN source files. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-06docs: add documentation for checkpatchDwaipayan Ray
Add documentation for kernel script checkpatch.pl. This documentation is also parsed by checkpatch to enable a verbose mode. The checkpatch message types are grouped by usage. Under each group the types are described briefly. 34 of such types are documented. Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com> Link: https://lore.kernel.org/r/20210226093827.12700-2-dwaipayanray1@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-26kasan: clarify that only first bug is reported in HW_TAGSAndrey Konovalov
Hwardware tag-based KASAN only reports the first found bug. After that MTE tag checking gets disabled. Clarify this in comments and documentation. Link: https://lkml.kernel.org/r/00383ba88a47c3f8342d12263c24bdf95527b07d.1612546384.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26kfence: report sensitive information based on no_hash_pointersMarco Elver
We cannot rely on CONFIG_DEBUG_KERNEL to decide if we're running a "debug kernel" where we can safely show potentially sensitive information in the kernel log. Instead, simply rely on the newly introduced "no_hash_pointers" to print unhashed kernel pointers, as well as decide if our reports can include other potentially sensitive information such as registers and corrupted bytes. Link: https://lkml.kernel.org/r/20210223082043.1972742-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Timur Tabi <timur@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@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>
2021-02-26kfence: add test suiteMarco Elver
Add KFENCE test suite, testing various error detection scenarios. Makes use of KUnit for test organization. Since KFENCE's interface to obtain error reports is via the console, the test verifies that KFENCE outputs expected reports to the console. [elver@google.com: fix typo in test] Link: https://lkml.kernel.org/r/X9lHQExmHGvETxY4@elver.google.com [elver@google.com: show access type in report] Link: https://lkml.kernel.org/r/20210111091544.3287013-2-elver@google.com Link: https://lkml.kernel.org/r/20201103175841.3495947-9-elver@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Marco Elver <elver@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Co-developed-by: Alexander Potapenko <glider@google.com> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christopher Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hillf Danton <hdanton@sina.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joern Engel <joern@purestorage.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: SeongJae Park <sjpark@amazon.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26kfence, Documentation: add KFENCE documentationMarco Elver
Add KFENCE documentation in dev-tools/kfence.rst, and add to index. [elver@google.com: add missing copyright header to documentation] Link: https://lkml.kernel.org/r/20210118092159.145934-4-elver@google.com Link: https://lkml.kernel.org/r/20201103175841.3495947-8-elver@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Marco Elver <elver@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Co-developed-by: Alexander Potapenko <glider@google.com> Reviewed-by: Jann Horn <jannh@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christopher Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hillf Danton <hdanton@sina.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joern Engel <joern@purestorage.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: SeongJae Park <sjpark@amazon.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24kasan: rename CONFIG_TEST_KASAN_MODULEAndrey Konovalov
Rename CONFIG_TEST_KASAN_MODULE to CONFIG_KASAN_MODULE_TEST. This naming is more consistent with the existing CONFIG_KASAN_KUNIT_TEST. Link: https://linux-review.googlesource.com/id/Id347dfa5fe8788b7a1a189863e039f409da0ae5f Link: https://lkml.kernel.org/r/f08250246683981bcf8a094fbba7c361995624d2.1610733117.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Reviewed-by: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24kasan: clarify HW_TAGS impact on TBIAndrey Konovalov
Mention in the documentation that enabling CONFIG_KASAN_HW_TAGS always results in in-kernel TBI (Top Byte Ignore) being enabled. Also do a few minor documentation cleanups. Link: https://linux-review.googlesource.com/id/Iba2a6697e3c6304cb53f89ec61dedc77fa29e3ae Link: https://lkml.kernel.org/r/3b4ea6875bb14d312092ad14ac55cb456c83c08e.1610733117.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Reviewed-by: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>