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
...
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
...
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>
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
...
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
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>
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>
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()
...
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
...
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
--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>
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>
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>
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>
