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>
(cherry picked from commit 2d27e58514)
Bug: 217221156
Change-Id: I5284fd8a4e8c2ddb1e06ca65bed133e35d70eb7f
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
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>
(cherry picked from commit 3ff16d30f5)
Bug: 217222520
Change-Id: If4a0747d9e25dafbfdc219b760ebe64b8e0c1676
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
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>
Bug: 170327579
Bug: 172318110
(cherry picked from commit 2603f8a78d
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/
for-next/mte-async-kernel-mode)
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I193e9eb0c016abc525ef69a1b9b2bb7254856162
Currently, whether the alloc/free stack traces collection is enabled by
default for hardware tag-based KASAN depends on CONFIG_DEBUG_KERNEL.
The intention for this dependency was to only enable collection on slow
debug kernels due to a significant perf and memory impact.
As it turns out, CONFIG_DEBUG_KERNEL is not considered a debug option
and is enabled on many productions kernels including Android and Ubuntu.
As the result, this dependency is pointless and only complicates the
code and documentation.
Having stack traces collection disabled by default would make the
hardware mode work differently to to the software ones, which is
confusing.
This change removes the dependency and enables stack traces collection
by default.
Looking into the future, this default might makes sense for production
kernels, assuming we implement a fast stack trace collection approach.
Link: https://lkml.kernel.org/r/6678d77ceffb71f1cff2cf61560e2ffe7bb6bfe9.1612808820.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 1cc4cdb521)
Bug: 172318110
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Change-Id: I450eb5405d988a2268fe3e0e171024c2de6f7fd7
Pull Kunit fixes from Shuah Khan:
"Several fixes to Kunit documentation and tools, and to not pollute
the source directory.
Also remove the incorrect kunit .gitattributes file"
* tag 'linux-kselftest-kunit-fixes-5.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: fix display of failed expectations for strings
kunit: tool: fix extra trailing \n in raw + parsed test output
kunit: tool: print out stderr from make (like build warnings)
KUnit: Docs: usage: wording fixes
KUnit: Docs: style: fix some Kconfig example issues
KUnit: Docs: fix a wording typo
kunit: Do not pollute source directory with generated files (test.log)
kunit: Do not pollute source directory with generated files (.kunitconfig)
kunit: tool: fix pre-existing python type annotation errors
kunit: Fix kunit.py parse subcommand (use null build_dir)
kunit: tool: unmark test_data as binary blobs
Pull Kunit fixes from Shuah Khan:
"Several kunit_tool and documentation fixes"
* tag 'linux-kselftest-kunit-fixes-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: tools: fix kunit_tool tests for parsing test plans
Documentation: kunit: Update Kconfig parts for KUNIT's module support
kunit: test: fix remaining kernel-doc warnings
kunit: Don't fail test suites if one of them is empty
kunit: Fix kunit.py --raw_output option
If 'CONFIG_KUNIT=m', letting kunit tests that do not support loadable
module build depends on 'KUNIT' instead of 'KUNIT=y' result in compile
errors. This commit updates the document for this.
Fixes: 9fe124bf1b ("kunit: allow kunit to be loaded as a module")
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull more Kunit updates from Shuah Khan:
- add Kunit to kernel_init() and remove KUnit from init calls entirely.
This addresses the concern that Kunit would not work correctly during
late init phase.
- add a linker section where KUnit can put references to its test
suites.
This is the first step in transitioning to dispatching all KUnit
tests from a centralized executor rather than having each as its own
separate late_initcall.
- add a centralized executor to dispatch tests rather than relying on
late_initcall to schedule each test suite separately. Centralized
execution is for built-in tests only; modules will execute tests when
loaded.
- convert bitfield test to use KUnit framework
- Documentation updates for naming guidelines and how
kunit_test_suite() works.
- add test plan to KUnit TAP format
* tag 'linux-kselftest-kunit-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
lib: kunit: Fix compilation test when using TEST_BIT_FIELD_COMPILE
lib: kunit: add bitfield test conversion to KUnit
Documentation: kunit: add a brief blurb about kunit_test_suite
kunit: test: add test plan to KUnit TAP format
init: main: add KUnit to kernel init
kunit: test: create a single centralized executor for all tests
vmlinux.lds.h: add linker section for KUnit test suites
Documentation: kunit: Add naming guidelines
Pull documentation updates from Mauro Carvalho Chehab:
"A series of patches addressing warnings produced by make htmldocs.
This includes:
- kernel-doc markup fixes
- ReST fixes
- Updates at the build system in order to support newer versions of
the docs build toolchain (Sphinx)
After this series, the number of html build warnings should reduce
significantly, and building with Sphinx 3.1 or later should now be
supported (although it is still recommended to use Sphinx 2.4.4).
As agreed with Jon, I should be sending you a late pull request by the
end of the merge window addressing remaining issues with docs build,
as there are a number of warning fixes that depends on pull requests
that should be happening along the merge window.
The end goal is to have a clean htmldocs build on Kernel 5.10.
PS. It should be noticed that Sphinx 3.0 is not currently supported,
as it lacks support for C domain namespaces. Such feature, needed in
order to document uAPI system calls with Sphinx 3.x, was added only on
Sphinx 3.1"
* tag 'docs/v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (75 commits)
PM / devfreq: remove a duplicated kernel-doc markup
mm/doc: fix a literal block markup
workqueue: fix a kernel-doc warning
docs: virt: user_mode_linux_howto_v2.rst: fix a literal block markup
Input: sparse-keymap: add a description for @sw
rcu/tree: docs: document bkvcache new members at struct kfree_rcu_cpu
nl80211: docs: add a description for s1g_cap parameter
usb: docs: document altmode register/unregister functions
kunit: test.h: fix a bad kernel-doc markup
drivers: core: fix kernel-doc markup for dev_err_probe()
docs: bio: fix a kerneldoc markup
kunit: test.h: solve kernel-doc warnings
block: bio: fix a warning at the kernel-doc markups
docs: powerpc: syscall64-abi.rst: fix a malformed table
drivers: net: hamradio: fix document location
net: appletalk: Kconfig: Fix docs location
dt-bindings: fix references to files converted to yaml
memblock: get rid of a :c:type leftover
math64.h: kernel-docs: Convert some markups into normal comments
media: uAPI: buffer.rst: remove a left-over documentation
...
Pull kselftest updates from Shuah Khan:
- speed up headers_install done during selftest build
- add generic make nesting support
- add support to select individual tests:
Selftests build/install generates run_kselftest.sh script to run
selftests on a target system. Currently the script doesn't have
support for selecting individual tests. Add support for it.
With this enhancement, user can select test collections (or tests)
individually. e.g:
run_kselftest.sh -c seccomp -t timers:posix_timers -t timers:nanosleep
Additionally adds a way to list all known tests with "-l", usage with
"-h", and perform a dry run without running tests with "-n".
* tag 'linux-kselftest-next-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
doc: dev-tools: kselftest.rst: Update examples and paths
selftests/run_kselftest.sh: Make each test individually selectable
selftests: Extract run_kselftest.sh and generate stand-alone test list
selftests: Add missing gitignore entries
selftests: more general make nesting support
selftests: use "$(MAKE)" instead of "make" for headers_install
Which Sphinx 3, :c:type: can't be used anymore for structs,
as this should be used only for typedefs.
Rely on automarkup.py for struct references.
This file has an special case, though: it uses the tag also
to point to an array. Let's use, instead, :c:expr: for such
purpose, as it should do the right thing.
This should fix this warning:
./Documentation/dev-tools/kgdb.rst:875: WARNING: Unparseable C cross-reference: 'kdb_poll_funcs[]'
Invalid C declaration: Expected end of definition. [error at 14]
kdb_poll_funcs[]
--------------^
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Pull documentation fixes from Jonathan Corbet:
"A handful of obvious fixes that wandered in during the merge window"
* tag 'docs-5.9-2' of git://git.lwn.net/linux:
Documentation/locking/locktypes: fix the typo
doc/zh_CN: resolve undefined label warning in admin-guide index
doc/zh_CN: fix title heading markup in admin-guide cpu-load
docs: remove the 2.6 "Upgrading I2C Drivers" guide
docs: Correct the release date of 5.2 stable
mailmap: Update comments for with format and more detalis
docs: cdrom: Fix a typo and rst markup
Doc: admin-guide: use correct legends in kernel-parameters.txt
Documentation/features: refresh RISC-V arch support files
documentation: coccinelle: Improve command example for make C={1,2}
Core-api: Documentation: Replace deprecated :c:func: Usage
Dev-tools: Documentation: Replace deprecated :c:func: Usage
Filesystems: Documentation: Replace deprecated :c:func: Usage
docs: trace: fix a typo
