The function tick_check_replacement() is the combination of
tick_check_percpu() and tick_check_preferred(), but tick_check_new_device()
has the same logic open coded.
Use the helper to simplify the code.
[ tglx: Massage changelog ]
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210326022328.3266-1-wangwensheng4@huawei.com
The current sched_slice() seems to have issues; there's two possible
things that could be improved:
- the 'nr_running' used for __sched_period() is daft when cgroups are
considered. Using the RQ wide h_nr_running seems like a much more
consistent number.
- (esp) cgroups can slice it real fine, which makes for easy
over-scheduling, ensure min_gran is what the name says.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210412102001.611897312@infradead.org
Move the #ifdef SCHED_DEBUG bits to kernel/sched/debug.c in order to
collect all the debugfs bits.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210412102001.353833279@infradead.org
Stop polluting sysctl with undocumented knobs that really are debug
only, move them all to /debug/sched/ along with the existing
/debug/sched_* files that already exist.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210412102001.287610138@infradead.org
CONFIG_SCHEDSTATS does not depend on SCHED_DEBUG, it is inconsistent
to have the sysctl depend on it.
Suggested-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210412102001.161151631@infradead.org
The ability to enable/disable NUMA balancing is not a debugging feature
and should not depend on CONFIG_SCHED_DEBUG. For example, machines within
a HPC cluster may disable NUMA balancing temporarily for some jobs and
re-enable it for other jobs without needing to reboot.
This patch removes the dependency on CONFIG_SCHED_DEBUG for
kernel.numa_balancing sysctl. The other numa balancing related sysctls
are left as-is because if they need to be tuned then it is more likely
that NUMA balancing needs to be fixed instead.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210324133916.GQ15768@suse.de
Use the new cpu_dying() state to simplify and fix the balance_push()
vs CPU hotplug rollback state.
Specifically, we currently rely on notifiers sched_cpu_dying() /
sched_cpu_activate() to terminate balance_push, however if the
cpu_down() fails when we're past sched_cpu_deactivate(), it should
terminate balance_push at that point and not wait until we hit
sched_cpu_activate().
Similarly, when cpu_up() fails and we're going back down, balance_push
should be active, where it currently is not.
So instead, make sure balance_push is enabled below SCHED_AP_ACTIVE
(when !cpu_active()), and gate it's utility with cpu_dying().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/YHgAYef83VQhKdC2@hirez.programming.kicks-ass.net
Introduce a cpumask that indicates (for each CPU) what direction the
CPU hotplug is currently going. Notably, it tracks rollbacks. Eg. when
an up fails and we do a roll-back down, it will accurately reflect the
direction.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210310150109.151441252@infradead.org
Adds bit perf_event_attr::sigtrap, which can be set to cause events to
send SIGTRAP (with si_code TRAP_PERF) to the task where the event
occurred. The primary motivation is to support synchronous signals on
perf events in the task where an event (such as breakpoints) triggered.
To distinguish perf events based on the event type, the type is set in
si_errno. For events that are associated with an address, si_addr is
copied from perf_sample_data.
The new field perf_event_attr::sig_data is copied to si_perf, which
allows user space to disambiguate which event (of the same type)
triggered the signal. For example, user space could encode the relevant
information it cares about in sig_data.
We note that the choice of an opaque u64 provides the simplest and most
flexible option. Alternatives where a reference to some user space data
is passed back suffer from the problem that modification of referenced
data (be it the event fd, or the perf_event_attr) can race with the
signal being delivered (of course, the same caveat applies if user space
decides to store a pointer in sig_data, but the ABI explicitly avoids
prescribing such a design).
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Link: https://lore.kernel.org/lkml/YBv3rAT566k+6zjg@hirez.programming.kicks-ass.net/
Introduces the TRAP_PERF si_code, and associated siginfo_t field
si_perf. These will be used by the perf event subsystem to send signals
(if requested) to the task where an event occurred.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Acked-by: Arnd Bergmann <arnd@arndb.de> # asm-generic
Link: https://lkml.kernel.org/r/20210408103605.1676875-6-elver@google.com
Adds bit perf_event_attr::remove_on_exec, to support removing an event
from a task on exec.
This option supports the case where an event is supposed to be
process-wide only, and should not propagate beyond exec, to limit
monitoring to the original process image only.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210408103605.1676875-5-elver@google.com
Adds bit perf_event_attr::inherit_thread, to restricting inheriting
events only if the child was cloned with CLONE_THREAD.
This option supports the case where an event is supposed to be
process-wide only (including subthreads), but should not propagate
beyond the current process's shared environment.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/lkml/YBvj6eJR%2FDY2TsEB@hirez.programming.kicks-ass.net/
As with other ioctls (such as PERF_EVENT_IOC_{ENABLE,DISABLE}), fix up
handling of PERF_EVENT_IOC_MODIFY_ATTRIBUTES to also apply to children.
Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Link: https://lkml.kernel.org/r/20210408103605.1676875-3-elver@google.com
Make perf_event_exit_event() more robust, such that we can use it from
other contexts. Specifically the up and coming remove_on_exec.
For this to work we need to address a few issues. Remove_on_exec will
not destroy the entire context, so we cannot rely on TASK_TOMBSTONE to
disable event_function_call() and we thus have to use
perf_remove_from_context().
When using perf_remove_from_context(), there's two races to consider.
The first is against close(), where we can have concurrent tear-down
of the event. The second is against child_list iteration, which should
not find a half baked event.
To address this, teach perf_remove_from_context() to special case
!ctx->is_active and about DETACH_CHILD.
[ elver@google.com: fix racing parent/child exit in sync_child_event(). ]
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210408103605.1676875-2-elver@google.com
Currently, we start allocating AUX pages half the size of the total
requested AUX buffer size, ignoring the attr.aux_watermark setting. This,
in turn, makes intel_pt driver disregard the watermark also, as it uses
page order for its SG (ToPA) configuration.
Now, this can be fixed in the intel_pt PMU driver, but seeing as it's the
only one currently making use of high order allocations, there is no
reason not to fix the allocator instead. This way, any other driver
wishing to add this support would not have to worry about this.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210414154955.49603-2-alexander.shishkin@linux.intel.com
Commit ec9c82e03a ("rseq: uapi: Declare rseq_cs field as union,
update includes") added regressions for our servers.
Using copy_from_user() and clear_user() for 64bit values
is suboptimal.
We can use faster put_user() and get_user() on 64bit arches.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lkml.kernel.org/r/20210413203352.71350-4-eric.dumazet@gmail.com
After commit 8f28177014 ("rseq: Use get_user/put_user rather
than __get_user/__put_user") we no longer need
an access_ok() call from __rseq_handle_notify_resume()
Mathieu pointed out the same cleanup can be done
in rseq_syscall().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lkml.kernel.org/r/20210413203352.71350-3-eric.dumazet@gmail.com
Two put_user() in rseq_update_cpu_id() are replaced
by a pair of unsafe_put_user() with appropriate surroundings.
This removes one stac/clac pair on x86 in fast path.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lkml.kernel.org/r/20210413203352.71350-2-eric.dumazet@gmail.com
The idea for this originates from the real time tree to make signal
delivery for realtime applications more efficient. In quite some of these
application scenarios a control tasks signals workers to start their
computations. There is usually only one signal per worker on flight. This
works nicely as long as the kmem cache allocations do not hit the slow path
and cause latencies.
To cure this an optimistic caching was introduced (limited to RT tasks)
which allows a task to cache a single sigqueue in a pointer in task_struct
instead of handing it back to the kmem cache after consuming a signal. When
the next signal is sent to the task then the cached sigqueue is used
instead of allocating a new one. This solved the problem for this set of
application scenarios nicely.
The task cache is not preallocated so the first signal sent to a task goes
always to the cache allocator. The cached sigqueue stays around until the
task exits and is freed when task::sighand is dropped.
After posting this solution for mainline the discussion came up whether
this would be useful in general and should not be limited to realtime
tasks: https://lore.kernel.org/r/m11rcu7nbr.fsf@fess.ebiederm.org
One concern leading to the original limitation was to avoid a large amount
of pointlessly cached sigqueues in alive tasks. The other concern was
vs. RLIMIT_SIGPENDING as these cached sigqueues are not accounted for.
The accounting problem is real, but on the other hand slightly academic.
After gathering some statistics it turned out that after boot of a regular
distro install there are less than 10 sigqueues cached in ~1500 tasks.
In case of a 'mass fork and fire signal to child' scenario the extra 80
bytes of memory per task are well in the noise of the overall memory
consumption of the fork bomb.
If this should be limited then this would need an extra counter in struct
user, more atomic instructions and a seperate rlimit. Yet another tunable
which is mostly unused.
The caching is actually used. After boot and a full kernel compile on a
64CPU machine with make -j128 the number of 'allocations' looks like this:
From slab: 23996
From task cache: 52223
I.e. it reduces the number of slab cache operations by ~68%.
A typical pattern there is:
<...>-58490 __sigqueue_alloc: for 58488 from slab ffff8881132df460
<...>-58488 __sigqueue_free: cache ffff8881132df460
<...>-58488 __sigqueue_alloc: for 1149 from cache ffff8881103dc550
bash-1149 exit_task_sighand: free ffff8881132df460
bash-1149 __sigqueue_free: cache ffff8881103dc550
The interesting sequence is that the exiting task 58488 grabs the sigqueue
from bash's task cache to signal exit and bash sticks it back into it's own
cache. Lather, rinse and repeat.
The caching is probably not noticable for the general use case, but the
benefit for latency sensitive applications is clear. While kmem caches are
usually just serving from the fast path the slab merging (default) can
depending on the usage pattern of the merged slabs cause occasional slow
path allocations.
The time spared per cached entry is a few micro seconds per signal which is
not relevant for e.g. a kernel build, but for signal heavy workloads it's
measurable.
As there is no real downside of this caching mechanism making it
unconditionally available is preferred over more conditional code or new
magic tunables.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/87sg4lbmxo.fsf@nanos.tec.linutronix.de
There is no point in having the conditional at the callsite.
Just hand in the allocation mode flag to __sigqueue_alloc() and use it to
initialize sigqueue::flags.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210322092258.898677147@linutronix.de
Add two new kdb environment access methods as kdb_setenv() and
kdb_printenv() in order to abstract out environment access code
from kdb command functions.
Also, replace (char *)0 with NULL as an initializer for environment
variables array.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/1612771342-16883-1-git-send-email-sumit.garg@linaro.org
[daniel.thompson@linaro.org: Replaced (char *)0/NULL initializers with
an array size]
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
allnoconfig_y is an ugly hack that sets a symbol to 'y' by allnoconfig.
allnoconfig does not mean a minimal set of CONFIG options because a
bunch of prompts are hidden by 'if EMBEDDED' or 'if EXPERT', but I do
not like to hack Kconfig this way.
Use the pre-existing feature, KCONFIG_ALLCONFIG, to provide a one
liner config fragment. CONFIG_EMBEDDED=y is still forced when
allnoconfig is invoked as a part of tinyconfig.
No change in the .config file produced by 'make tinyconfig'.
The output of 'make allnoconfig' will be changed; we will get
CONFIG_EMBEDDED=n because allnoconfig literally sets all symbols to n.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
An error path exited the function before freeing the allocated
"argv" variable.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCYHY3LRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qigOAPwOvbUI9PQTW3hs16XHDGbgtzdzX6A7
kF7GlId5tXbZDwD/bW2gilFCjULCEPDuqsDy5EXrbZ7V7kulOfIw2e8CAQM=
=HwKu
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Fix a memory link in dyn_event_release().
An error path exited the function before freeing the allocated 'argv'
variable"
* tag 'trace-v5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/dynevent: Fix a memory leak in an error handling path
There is currently no way to discover the target of a tracing program
attachment after the fact. Add this information to bpf_link_info and return
it when querying the bpf_link fd.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210413091607.58945-1-toke@redhat.com
This change introduces a prctl that allows the user program to control
which PAC keys are enabled in a particular task. The main reason
why this is useful is to enable a userspace ABI that uses PAC to
sign and authenticate function pointers and other pointers exposed
outside of the function, while still allowing binaries conforming
to the ABI to interoperate with legacy binaries that do not sign or
authenticate pointers.
The idea is that a dynamic loader or early startup code would issue
this prctl very early after establishing that a process may load legacy
binaries, but before executing any PAC instructions.
This change adds a small amount of overhead to kernel entry and exit
due to additional required instruction sequences.
On a DragonBoard 845c (Cortex-A75) with the powersave governor, the
overhead of similar instruction sequences was measured as 4.9ns when
simulating the common case where IA is left enabled, or 43.7ns when
simulating the uncommon case where IA is disabled. These numbers can
be seen as the worst case scenario, since in more realistic scenarios
a better performing governor would be used and a newer chip would be
used that would support PAC unlike Cortex-A75 and would be expected
to be faster than Cortex-A75.
On an Apple M1 under a hypervisor, the overhead of the entry/exit
instruction sequences introduced by this patch was measured as 0.3ns
in the case where IA is left enabled, and 33.0ns in the case where
IA is disabled.
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://linux-review.googlesource.com/id/Ibc41a5e6a76b275efbaa126b31119dc197b927a5
Link: https://lore.kernel.org/r/d6609065f8f40397a4124654eb68c9f490b4d477.1616123271.git.pcc@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Change hierachy to hierarchy and unrechable to unreachable,
no functionality changed.
Signed-off-by: Lu Jialin <lujialin4@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull ARM cpufreq updates for v5.13 from Viresh Kumar:
"- Fix typos in s5pv210 cpufreq driver (Bhaskar Chowdhury).
- Armada 37xx: Fix cpufreq changing base CPU speed to 800 MHz from
1000 MHz (Pali Rohár and Marek Behún).
- cpufreq-dt: Return -EPROBE_DEFER on failure to add table (Quanyang
Wang).
- Minor cleanup in cppc driver (Tom Saeger).
- Add frequency invariance support for CPPC driver and generalize
freq invariance support arch-topology driver (Viresh Kumar)."
* 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
cpufreq: armada-37xx: Fix module unloading
cpufreq: armada-37xx: Remove cur_frequency variable
cpufreq: armada-37xx: Fix determining base CPU frequency
cpufreq: armada-37xx: Fix driver cleanup when registration failed
clk: mvebu: armada-37xx-periph: Fix workaround for switching from L1 to L0
clk: mvebu: armada-37xx-periph: Fix switching CPU freq from 250 Mhz to 1 GHz
cpufreq: armada-37xx: Fix the AVS value for load L1
clk: mvebu: armada-37xx-periph: remove .set_parent method for CPU PM clock
cpufreq: armada-37xx: Fix setting TBG parent for load levels
cpufreq: dt: dev_pm_opp_of_cpumask_add_table() may return -EPROBE_DEFER
cpufreq: cppc: simplify default delay_us setting
cpufreq: Rudimentary typos fix in the file s5pv210-cpufreq.c
cpufreq: CPPC: Add support for frequency invariance
arch_topology: Export arch_freq_scale and helpers
arch_topology: Allow multiple entities to provide sched_freq_tick() callback
arch_topology: Rename freq_scale as arch_freq_scale
The only exported helper we have right now is task_work_cancel(), which
cancels any task_work from a given task where func matches the queued
work item. This is a bit too coarse for some use cases. Add a
task_work_cancel_match() that allows to more specifically target
individual work items outside of purely the callback function used.
task_work_cancel() can be trivially implemented on top of that, hence do
so.
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
fork() fails if signal_pending() is true, but there are two conditions
that can lead to that:
1) An actual signal is pending. We want fork to fail for that one, like
we always have.
2) TIF_NOTIFY_SIGNAL is pending, because the task has pending task_work.
We don't need to make it fail for that case.
Allow fork() to proceed if just task_work is pending, by changing the
signal_pending() check to task_sigpending().
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ambiguous/confusing kernel log message.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=y7/k
-----END PGP SIGNATURE-----
Merge tag 'locking-urgent-2021-04-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixlets from Ingo Molnar:
"Two minor fixes: one for a Clang warning, the other improves an
ambiguous/confusing kernel log message"
* tag 'locking-urgent-2021-04-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
lockdep: Address clang -Wformat warning printing for %hd
lockdep: Add a missing initialization hint to the "INFO: Trying to register non-static key" message
Pull RCU changes from Paul E. McKenney:
- Bitmap support for "N" as alias for last bit
- kvfree_rcu updates
- mm_dump_obj() updates. (One of these is to mm, but was suggested by Andrew Morton.)
- RCU callback offloading update
- Polling RCU grace-period interfaces
- Realtime-related RCU updates
- Tasks-RCU updates
- Torture-test updates
- Torture-test scripting updates
- Miscellaneous fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
note_interrupt() increments desc->irq_count for each interrupt even for
percpu interrupt handlers, even when they are handled successfully. This
causes cacheline bouncing and limits scalability.
Instead of incrementing irq_count every time, only start incrementing it
after seeing an unhandled irq, which should avoid the cache line
bouncing in the common path.
This actually should give better consistency in handling misbehaving
irqs too, because instead of the first unhandled irq arriving at an
arbitrary point in the irq_count cycle, its arrival will begin the
irq_count cycle.
Cédric reports the result of his IPI throughput test:
Millions of IPIs/s
----------- --------------------------------------
upstream upstream patched
chips cpus default noirqdebug default (irqdebug)
----------- -----------------------------------------
1 0-15 4.061 4.153 4.084
0-31 7.937 8.186 8.158
0-47 11.018 11.392 11.233
0-63 11.460 13.907 14.022
2 0-79 8.376 18.105 18.084
0-95 7.338 22.101 22.266
0-111 6.716 25.306 25.473
0-127 6.223 27.814 28.029
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210402132037.574661-1-npiggin@gmail.com
KMSAN complains that new_value at cpumask_parse_user() from
write_irq_affinity() from irq_affinity_proc_write() is uninitialized.
[ 148.133411][ T5509] =====================================================
[ 148.135383][ T5509] BUG: KMSAN: uninit-value in find_next_bit+0x325/0x340
[ 148.137819][ T5509]
[ 148.138448][ T5509] Local variable ----new_value.i@irq_affinity_proc_write created at:
[ 148.140768][ T5509] irq_affinity_proc_write+0xc3/0x3d0
[ 148.142298][ T5509] irq_affinity_proc_write+0xc3/0x3d0
[ 148.143823][ T5509] =====================================================
Since bitmap_parse() from cpumask_parse_user() calls find_next_bit(),
any alloc_cpumask_var() + cpumask_parse_user() sequence has possibility
that find_next_bit() accesses uninitialized cpu mask variable. Fix this
problem by replacing alloc_cpumask_var() with zalloc_cpumask_var().
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20210401055823.3929-1-penguin-kernel@I-love.SAKURA.ne.jp
Conflicts:
MAINTAINERS
- keep Chandrasekar
drivers/net/ethernet/mellanox/mlx5/core/en_main.c
- simple fix + trust the code re-added to param.c in -next is fine
include/linux/bpf.h
- trivial
include/linux/ethtool.h
- trivial, fix kdoc while at it
include/linux/skmsg.h
- move to relevant place in tcp.c, comment re-wrapped
net/core/skmsg.c
- add the sk = sk // sk = NULL around calls
net/tipc/crypto.c
- trivial
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge misc fixes from Andrew Morton:
"14 patches.
Subsystems affected by this patch series: mm (kasan, gup, pagecache,
and kfence), MAINTAINERS, mailmap, nds32, gcov, ocfs2, ia64, and lib"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
lib: fix kconfig dependency on ARCH_WANT_FRAME_POINTERS
kfence, x86: fix preemptible warning on KPTI-enabled systems
lib/test_kasan_module.c: suppress unused var warning
kasan: fix conflict with page poisoning
fs: direct-io: fix missing sdio->boundary
ia64: fix user_stack_pointer() for ptrace()
ocfs2: fix deadlock between setattr and dio_end_io_write
gcov: re-fix clang-11+ support
nds32: flush_dcache_page: use page_mapping_file to avoid races with swapoff
mm/gup: check page posion status for coredump.
.mailmap: fix old email addresses
mailmap: update email address for Jordan Crouse
treewide: change my e-mail address, fix my name
MAINTAINERS: update CZ.NIC's Turris information
mac80211, wireless, and bpf trees. No scary regressions here
or in the works, but small fixes for 5.12 changes keep coming.
Current release - regressions:
- virtio: do not pull payload in skb->head
- virtio: ensure mac header is set in virtio_net_hdr_to_skb()
- Revert "net: correct sk_acceptq_is_full()"
- mptcp: revert "mptcp: provide subflow aware release function"
- ethernet: lan743x: fix ethernet frame cutoff issue
- dsa: fix type was not set for devlink port
- ethtool: remove link_mode param and derive link params
from driver
- sched: htb: fix null pointer dereference on a null new_q
- wireless: iwlwifi: Fix softirq/hardirq disabling in
iwl_pcie_enqueue_hcmd()
- wireless: iwlwifi: fw: fix notification wait locking
- wireless: brcmfmac: p2p: Fix deadlock introduced by avoiding
the rtnl dependency
Current release - new code bugs:
- napi: fix hangup on napi_disable for threaded napi
- bpf: take module reference for trampoline in module
- wireless: mt76: mt7921: fix airtime reporting and related
tx hangs
- wireless: iwlwifi: mvm: rfi: don't lock mvm->mutex when sending
config command
Previous releases - regressions:
- rfkill: revert back to old userspace API by default
- nfc: fix infinite loop, refcount & memory leaks in LLCP sockets
- let skb_orphan_partial wake-up waiters
- xfrm/compat: Cleanup WARN()s that can be user-triggered
- vxlan, geneve: do not modify the shared tunnel info when PMTU
triggers an ICMP reply
- can: fix msg_namelen values depending on CAN_REQUIRED_SIZE
- can: uapi: mark union inside struct can_frame packed
- sched: cls: fix action overwrite reference counting
- sched: cls: fix err handler in tcf_action_init()
- ethernet: mlxsw: fix ECN marking in tunnel decapsulation
- ethernet: nfp: Fix a use after free in nfp_bpf_ctrl_msg_rx
- ethernet: i40e: fix receiving of single packets in xsk zero-copy
mode
- ethernet: cxgb4: avoid collecting SGE_QBASE regs during traffic
Previous releases - always broken:
- bpf: Refuse non-O_RDWR flags in BPF_OBJ_GET
- bpf: Refcount task stack in bpf_get_task_stack
- bpf, x86: Validate computation of branch displacements
- ieee802154: fix many similar syzbot-found bugs
- fix NULL dereferences in netlink attribute handling
- reject unsupported operations on monitor interfaces
- fix error handling in llsec_key_alloc()
- xfrm: make ipv4 pmtu check honor ip header df
- xfrm: make hash generation lock per network namespace
- xfrm: esp: delete NETIF_F_SCTP_CRC bit from features for esp
offload
- ethtool: fix incorrect datatype in set_eee ops
- xdp: fix xdp_return_frame() kernel BUG throw for page_pool
memory model
- openvswitch: fix send of uninitialized stack memory in ct limit
reply
Misc:
- udp: add get handling for UDP_GRO sockopt
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=SHL0
-----END PGP SIGNATURE-----
Merge tag 'net-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Networking fixes for 5.12-rc7, including fixes from can, ipsec,
mac80211, wireless, and bpf trees.
No scary regressions here or in the works, but small fixes for 5.12
changes keep coming.
Current release - regressions:
- virtio: do not pull payload in skb->head
- virtio: ensure mac header is set in virtio_net_hdr_to_skb()
- Revert "net: correct sk_acceptq_is_full()"
- mptcp: revert "mptcp: provide subflow aware release function"
- ethernet: lan743x: fix ethernet frame cutoff issue
- dsa: fix type was not set for devlink port
- ethtool: remove link_mode param and derive link params from driver
- sched: htb: fix null pointer dereference on a null new_q
- wireless: iwlwifi: Fix softirq/hardirq disabling in
iwl_pcie_enqueue_hcmd()
- wireless: iwlwifi: fw: fix notification wait locking
- wireless: brcmfmac: p2p: Fix deadlock introduced by avoiding the
rtnl dependency
Current release - new code bugs:
- napi: fix hangup on napi_disable for threaded napi
- bpf: take module reference for trampoline in module
- wireless: mt76: mt7921: fix airtime reporting and related tx hangs
- wireless: iwlwifi: mvm: rfi: don't lock mvm->mutex when sending
config command
Previous releases - regressions:
- rfkill: revert back to old userspace API by default
- nfc: fix infinite loop, refcount & memory leaks in LLCP sockets
- let skb_orphan_partial wake-up waiters
- xfrm/compat: Cleanup WARN()s that can be user-triggered
- vxlan, geneve: do not modify the shared tunnel info when PMTU
triggers an ICMP reply
- can: fix msg_namelen values depending on CAN_REQUIRED_SIZE
- can: uapi: mark union inside struct can_frame packed
- sched: cls: fix action overwrite reference counting
- sched: cls: fix err handler in tcf_action_init()
- ethernet: mlxsw: fix ECN marking in tunnel decapsulation
- ethernet: nfp: Fix a use after free in nfp_bpf_ctrl_msg_rx
- ethernet: i40e: fix receiving of single packets in xsk zero-copy
mode
- ethernet: cxgb4: avoid collecting SGE_QBASE regs during traffic
Previous releases - always broken:
- bpf: Refuse non-O_RDWR flags in BPF_OBJ_GET
- bpf: Refcount task stack in bpf_get_task_stack
- bpf, x86: Validate computation of branch displacements
- ieee802154: fix many similar syzbot-found bugs
- fix NULL dereferences in netlink attribute handling
- reject unsupported operations on monitor interfaces
- fix error handling in llsec_key_alloc()
- xfrm: make ipv4 pmtu check honor ip header df
- xfrm: make hash generation lock per network namespace
- xfrm: esp: delete NETIF_F_SCTP_CRC bit from features for esp
offload
- ethtool: fix incorrect datatype in set_eee ops
- xdp: fix xdp_return_frame() kernel BUG throw for page_pool memory
model
- openvswitch: fix send of uninitialized stack memory in ct limit
reply
Misc:
- udp: add get handling for UDP_GRO sockopt"
* tag 'net-5.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (182 commits)
net: fix hangup on napi_disable for threaded napi
net: hns3: Trivial spell fix in hns3 driver
lan743x: fix ethernet frame cutoff issue
net: ipv6: check for validity before dereferencing cfg->fc_nlinfo.nlh
net: dsa: lantiq_gswip: Configure all remaining GSWIP_MII_CFG bits
net: dsa: lantiq_gswip: Don't use PHY auto polling
net: sched: sch_teql: fix null-pointer dereference
ipv6: report errors for iftoken via netlink extack
net: sched: fix err handler in tcf_action_init()
net: sched: fix action overwrite reference counting
Revert "net: sched: bump refcount for new action in ACT replace mode"
ice: fix memory leak of aRFS after resuming from suspend
i40e: Fix sparse warning: missing error code 'err'
i40e: Fix sparse error: 'vsi->netdev' could be null
i40e: Fix sparse error: uninitialized symbol 'ring'
i40e: Fix sparse errors in i40e_txrx.c
i40e: Fix parameters in aq_get_phy_register()
nl80211: fix beacon head validation
bpf, x86: Validate computation of branch displacements for x86-32
bpf, x86: Validate computation of branch displacements for x86-64
...
LLVM changed the expected function signature for llvm_gcda_emit_function()
in the clang-11 release. Users of clang-11 or newer may have noticed
their kernels producing invalid coverage information:
$ llvm-cov gcov -a -c -u -f -b <input>.gcda -- gcno=<input>.gcno
1 <func>: checksum mismatch, \
(<lineno chksum A>, <cfg chksum B>) != (<lineno chksum A>, <cfg chksum C>)
2 Invalid .gcda File!
...
Fix up the function signatures so calling this function interprets its
parameters correctly and computes the correct cfg checksum. In
particular, in clang-11, the additional checksum is no longer optional.
Link: https://reviews.llvm.org/rG25544ce2df0daa4304c07e64b9c8b0f7df60c11d
Link: https://lkml.kernel.org/r/20210408184631.1156669-1-ndesaulniers@google.com
Reported-by: Prasad Sodagudi <psodagud@quicinc.com>
Tested-by: Prasad Sodagudi <psodagud@quicinc.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Cc: <stable@vger.kernel.org> [5.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During load-balance, groups classified as group_misfit_task are filtered
out if they do not pass
group_smaller_max_cpu_capacity(<candidate group>, <local group>);
which itself employs fits_capacity() to compare the sgc->max_capacity of
both groups.
Due to the underlying margin, fits_capacity(X, 1024) will return false for
any X > 819. Tough luck, the capacity_orig's on e.g. the Pixel 4 are
{261, 871, 1024}. If a CPU-bound task ends up on one of those "medium"
CPUs, misfit migration will never intentionally upmigrate it to a CPU of
higher capacity due to the aforementioned margin.
One may argue the 20% margin of fits_capacity() is excessive in the advent
of counter-enhanced load tracking (APERF/MPERF, AMUs), but one point here
is that fits_capacity() is meant to compare a utilization value to a
capacity value, whereas here it is being used to compare two capacity
values. As CPU capacity and task utilization have different dynamics, a
sensible approach here would be to add a new helper dedicated to comparing
CPU capacities.
Also note that comparing capacity extrema of local and source sched_group's
doesn't make much sense when at the day of the day the imbalance will be
pulled by a known env->dst_cpu, whose capacity can be anywhere within the
local group's capacity extrema.
While at it, replace group_smaller_{min, max}_cpu_capacity() with
comparisons of the source group's min/max capacity and the destination
CPU's capacity.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>
Link: https://lkml.kernel.org/r/20210407220628.3798191-4-valentin.schneider@arm.com
When triggering an active load balance, sd->nr_balance_failed is set to
such a value that any further can_migrate_task() using said sd will ignore
the output of task_hot().
This behaviour makes sense, as active load balance intentionally preempts a
rq's running task to migrate it right away, but this asynchronous write is
a bit shoddy, as the stopper thread might run active_load_balance_cpu_stop
before the sd->nr_balance_failed write either becomes visible to the
stopper's CPU or even happens on the CPU that appended the stopper work.
Add a struct lb_env flag to denote active balancing, and use it in
can_migrate_task(). Remove the sd->nr_balance_failed write that served the
same purpose. Cleanup the LBF_DST_PINNED active balance special case.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20210407220628.3798191-3-valentin.schneider@arm.com
During load balance, LBF_SOME_PINNED will be set if any candidate task
cannot be detached due to CPU affinity constraints. This can result in
setting env->sd->parent->sgc->group_imbalance, which can lead to a group
being classified as group_imbalanced (rather than any of the other, lower
group_type) when balancing at a higher level.
In workloads involving a single task per CPU, LBF_SOME_PINNED can often be
set due to per-CPU kthreads being the only other runnable tasks on any
given rq. This results in changing the group classification during
load-balance at higher levels when in reality there is nothing that can be
done for this affinity constraint: per-CPU kthreads, as the name implies,
don't get to move around (modulo hotplug shenanigans).
It's not as clear for userspace tasks - a task could be in an N-CPU cpuset
with N-1 offline CPUs, making it an "accidental" per-CPU task rather than
an intended one. KTHREAD_IS_PER_CPU gives us an indisputable signal which
we can leverage here to not set LBF_SOME_PINNED.
Note that the aforementioned classification to group_imbalance (when
nothing can be done) is especially problematic on big.LITTLE systems, which
have a topology the likes of:
DIE [ ]
MC [ ][ ]
0 1 2 3
L L B B
arch_scale_cpu_capacity(L) < arch_scale_cpu_capacity(B)
Here, setting LBF_SOME_PINNED due to a per-CPU kthread when balancing at MC
level on CPUs [0-1] will subsequently prevent CPUs [2-3] from classifying
the [0-1] group as group_misfit_task when balancing at DIE level. Thus, if
CPUs [0-1] are running CPU-bound (misfit) tasks, ill-timed per-CPU kthreads
can significantly delay the upgmigration of said misfit tasks. Systems
relying on ASYM_PACKING are likely to face similar issues.
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>
[Use kthread_is_per_cpu() rather than p->nr_cpus_allowed]
[Reword changelog]
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20210407220628.3798191-2-valentin.schneider@arm.com
Mel Gorman did some nice work in 9fe1f127b9 ("sched/fair: Merge
select_idle_core/cpu()"), resulting in the kernel being more efficient
at finding an idle CPU, and in tasks spending less time waiting to be
run, both according to the schedstats run_delay numbers, and according
to measured application latencies. Yay.
The flip side of this is that we see more task migrations (about 30%
more), higher cache misses, higher memory bandwidth utilization, and
higher CPU use, for the same number of requests/second.
This is most pronounced on a memcache type workload, which saw a
consistent 1-3% increase in total CPU use on the system, due to those
increased task migrations leading to higher L2 cache miss numbers, and
higher memory utilization. The exclusive L3 cache on Skylake does us
no favors there.
On our web serving workload, that effect is usually negligible.
It appears that the increased number of CPU migrations is generally a
good thing, since it leads to lower cpu_delay numbers, reflecting the
fact that tasks get to run faster. However, the reduced locality and
the corresponding increase in L2 cache misses hurts a little.
The patch below appears to fix the regression, while keeping the
benefit of the lower cpu_delay numbers, by reintroducing
select_idle_smt with a twist: when a socket has no idle cores, check
to see if the sibling of "prev" is idle, before searching all the
other CPUs.
This fixes both the occasional 9% regression on the web serving
workload, and the continuous 2% CPU use regression on the memcache
type workload.
With Mel's patches and this patch together, task migrations are still
high, but L2 cache misses, memory bandwidth, and CPU time used are
back down to what they were before. The p95 and p99 response times for
the memcache type application improve by about 10% over what they were
before Mel's patches got merged.
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20210326151932.2c187840@imladris.surriel.com
static_call_update() had stronger type requirements than regular C,
relax them to match. Instead of requiring the @func argument has the
exact matching type, allow any type which C is willing to promote to the
right (function) pointer type. Specifically this allows (void *)
arguments.
This cleans up a bunch of static_call_update() callers for
PREEMPT_DYNAMIC and should get around silly GCC11 warnings for free.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/YFoN7nCl8OfGtpeh@hirez.programming.kicks-ass.net
Here is the warning converted as error and reported by GCC:
kernel/static_call.c: In function ‘__static_call_update’:
kernel/static_call.c:153:18: error: unused variable ‘mod’ [-Werror=unused-variable]
153 | struct module *mod = site_mod->mod;
| ^~~
cc1: all warnings being treated as errors
make[1]: *** [scripts/Makefile.build:271: kernel/static_call.o] Error 1
This is simply because since recently, we no longer use 'mod' variable
elsewhere if MODULE is unset.
When using 'make tinyconfig' to generate the default kconfig, MODULE is
unset.
There are different ways to fix this warning. Here I tried to minimised
the number of modified lines and not add more #ifdef. We could also move
the declaration of the 'mod' variable inside the if-statement or
directly use site_mod->mod.
Fixes: 698bacefe9 ("static_call: Align static_call_is_init() patching condition")
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210326105023.2058860-1-matthieu.baerts@tessares.net
With CONFIG_CFI_CLANG and ThinLTO, Clang appends a hash to the names
of all static functions not marked __used. This can break userspace
tools that don't expect the function name to change, so strip out the
hash from the output.
Suggested-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-8-samitolvanen@google.com
With CONFIG_CFI_CLANG, a callback function passed to
__kthread_queue_delayed_work from a module points to a jump table
entry defined in the module instead of the one used in the core
kernel, which breaks function address equality in this check:
WARN_ON_ONCE(timer->function != ktead_delayed_work_timer_fn);
Use WARN_ON_FUNCTION_MISMATCH() instead to disable the warning
when CFI and modules are both enabled.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-7-samitolvanen@google.com
With CONFIG_CFI_CLANG, a callback function passed to
__queue_delayed_work from a module points to a jump table entry
defined in the module instead of the one used in the core kernel,
which breaks function address equality in this check:
WARN_ON_ONCE(timer->function != delayed_work_timer_fn);
Use WARN_ON_FUNCTION_MISMATCH() instead to disable the warning
when CFI and modules are both enabled.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-6-samitolvanen@google.com
This change adds support for Clang’s forward-edge Control Flow
Integrity (CFI) checking. With CONFIG_CFI_CLANG, the compiler
injects a runtime check before each indirect function call to ensure
the target is a valid function with the correct static type. This
restricts possible call targets and makes it more difficult for
an attacker to exploit bugs that allow the modification of stored
function pointers. For more details, see:
https://clang.llvm.org/docs/ControlFlowIntegrity.html
Clang requires CONFIG_LTO_CLANG to be enabled with CFI to gain
visibility to possible call targets. Kernel modules are supported
with Clang’s cross-DSO CFI mode, which allows checking between
independently compiled components.
With CFI enabled, the compiler injects a __cfi_check() function into
the kernel and each module for validating local call targets. For
cross-module calls that cannot be validated locally, the compiler
calls the global __cfi_slowpath_diag() function, which determines
the target module and calls the correct __cfi_check() function. This
patch includes a slowpath implementation that uses __module_address()
to resolve call targets, and with CONFIG_CFI_CLANG_SHADOW enabled, a
shadow map that speeds up module look-ups by ~3x.
Clang implements indirect call checking using jump tables and
offers two methods of generating them. With canonical jump tables,
the compiler renames each address-taken function to <function>.cfi
and points the original symbol to a jump table entry, which passes
__cfi_check() validation. This isn’t compatible with stand-alone
assembly code, which the compiler doesn’t instrument, and would
result in indirect calls to assembly code to fail. Therefore, we
default to using non-canonical jump tables instead, where the compiler
generates a local jump table entry <function>.cfi_jt for each
address-taken function, and replaces all references to the function
with the address of the jump table entry.
Note that because non-canonical jump table addresses are local
to each component, they break cross-module function address
equality. Specifically, the address of a global function will be
different in each module, as it's replaced with the address of a local
jump table entry. If this address is passed to a different module,
it won’t match the address of the same function taken there. This
may break code that relies on comparing addresses passed from other
components.
CFI checking can be disabled in a function with the __nocfi attribute.
Additionally, CFI can be disabled for an entire compilation unit by
filtering out CC_FLAGS_CFI.
By default, CFI failures result in a kernel panic to stop a potential
exploit. CONFIG_CFI_PERMISSIVE enables a permissive mode, where the
kernel prints out a rate-limited warning instead, and allows execution
to continue. This option is helpful for locating type mismatches, but
should only be enabled during development.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-2-samitolvanen@google.com
Currently only root can write files under /proc/pressure. Relax this to
allow tasks running as unprivileged users with CAP_SYS_RESOURCE to be
able to write to these files.
Signed-off-by: Josh Hunt <johunt@akamai.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/20210402025833.27599-1-johunt@akamai.com
Change "occured" to "occurred" in kernel/power/autosleep.c.
Change "consiting" to "consisting" in kernel/power/snapshot.c.
Change "avaiable" to "available" in kernel/power/swap.c.
No functionality changed.
Signed-off-by: Lu Jialin <lujialin4@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Make the tick_nohz_get_next_hrtimer() kerneldoc comment state clearly
that the function may return negative numbers.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
bpf_preload_lock is already defined with DEFINE_MUTEX(). There is no
need to initialize it again. Remove the extraneous initialization.
Signed-off-by: Muhammad Usama Anjum <musamaanjum@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210405194904.GA148013@LEGION
Secure Encrypted Virtualization (SEV) and Secure Encrypted
Virtualization - Encrypted State (SEV-ES) ASIDs are used to encrypt KVMs
on AMD platform. These ASIDs are available in the limited quantities on
a host.
Register their capacity and usage to the misc controller for tracking
via cgroups.
Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: David Rientjes <rientjes@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The Miscellaneous cgroup provides the resource limiting and tracking
mechanism for the scalar resources which cannot be abstracted like the
other cgroup resources. Controller is enabled by the CONFIG_CGROUP_MISC
config option.
A resource can be added to the controller via enum misc_res_type{} in
the include/linux/misc_cgroup.h file and the corresponding name via
misc_res_name[] in the kernel/cgroup/misc.c file. Provider of the
resource must set its capacity prior to using the resource by calling
misc_cg_set_capacity().
Once a capacity is set then the resource usage can be updated using
charge and uncharge APIs. All of the APIs to interact with misc
controller are in include/linux/misc_cgroup.h.
Miscellaneous controller provides 3 interface files. If two misc
resources (res_a and res_b) are registered then:
misc.capacity
A read-only flat-keyed file shown only in the root cgroup. It shows
miscellaneous scalar resources available on the platform along with
their quantities::
$ cat misc.capacity
res_a 50
res_b 10
misc.current
A read-only flat-keyed file shown in the non-root cgroups. It shows
the current usage of the resources in the cgroup and its children::
$ cat misc.current
res_a 3
res_b 0
misc.max
A read-write flat-keyed file shown in the non root cgroups. Allowed
maximum usage of the resources in the cgroup and its children.::
$ cat misc.max
res_a max
res_b 4
Limit can be set by::
# echo res_a 1 > misc.max
Limit can be set to max by::
# echo res_a max > misc.max
Limits can be set more than the capacity value in the misc.capacity
file.
Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: David Rientjes <rientjes@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
84;0;0c84;0;0c
There are two workqueue-specific watchdog timestamps:
+ @wq_watchdog_touched_cpu (per-CPU) updated by
touch_softlockup_watchdog()
+ @wq_watchdog_touched (global) updated by
touch_all_softlockup_watchdogs()
watchdog_timer_fn() checks only the global @wq_watchdog_touched for
unbound workqueues. As a result, unbound workqueues are not aware
of touch_softlockup_watchdog(). The watchdog might report a stall
even when the unbound workqueues are blocked by a known slow code.
Solution:
touch_softlockup_watchdog() must touch also the global @wq_watchdog_touched
timestamp.
The global timestamp can no longer be used for bound workqueues because
it is now updated from all CPUs. Instead, bound workqueues have to check
only @wq_watchdog_touched_cpu and these timestamps have to be updated for
all CPUs in touch_all_softlockup_watchdogs().
Beware:
The change might cause the opposite problem. An unbound workqueue
might get blocked on CPU A because of a real softlockup. The workqueue
watchdog would miss it when the timestamp got touched on CPU B.
It is acceptable because softlockups are detected by softlockup
watchdog. The workqueue watchdog is there to detect stalls where
a work never finishes, for example, because of dependencies of works
queued into the same workqueue.
V3:
- Modify the commit message clearly according to Petr's suggestion.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The debug_work_activate() is called on the premise that
the work can be inserted, because if wq be in WQ_DRAINING
status, insert work may be failed.
Fixes: e41e704bc4 ("workqueue: improve destroy_workqueue() debuggability")
Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
'stack' parameter is not used in ___bpf_prog_run() after f696b8f471
("bpf: split bpf core interpreter"), the base address have been set to
FP reg. So consequently remove it.
Signed-off-by: He Fengqing <hefengqing@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210331075135.3850782-1-hefengqing@huawei.com
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-04-01
The following pull-request contains BPF updates for your *net-next* tree.
We've added 68 non-merge commits during the last 7 day(s) which contain
a total of 70 files changed, 2944 insertions(+), 1139 deletions(-).
The main changes are:
1) UDP support for sockmap, from Cong.
2) Verifier merge conflict resolution fix, from Daniel.
3) xsk selftests enhancements, from Maciej.
4) Unstable helpers aka kernel func calling, from Martin.
5) Batches ops for LPM map, from Pedro.
6) Fix race in bpf_get_local_storage, from Yonghong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The macro that creates both the structure and the format displayed
to user space for the stack trace event was changed a while ago
to fix the parsing by user space tooling. But this change also modified
the structure used to store the stack trace event. It changed the
caller array field from [0] to [8]. Even though the size in the ring
buffer is dynamic and can be something other than 8 (user space knows
how to handle this), the 8 extra words was not accounted for when
reserving the event on the ring buffer, and added 8 more entries, due
to the calculation of "sizeof(*entry) + nr_entries * sizeof(long)",
as the sizeof(*entry) now contains 8 entries. The size of the caller
field needs to be subtracted from the size of the entry to create
the correct allocation size.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCYGccURQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qiboAPwNM1q8A7EFLDGfj+3tXksvp4H3hXd3
ErMd2OMlsNQtRAD9GGmYyt2OtFdxZWzKOSEC07vdxq2TYTz50mqJM81YbgE=
=7hwx
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.12-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Fix stack trace entry size to stop showing garbage
The macro that creates both the structure and the format displayed to
user space for the stack trace event was changed a while ago to fix
the parsing by user space tooling. But this change also modified the
structure used to store the stack trace event. It changed the caller
array field from [0] to [8].
Even though the size in the ring buffer is dynamic and can be
something other than 8 (user space knows how to handle this), the 8
extra words was not accounted for when reserving the event on the ring
buffer, and added 8 more entries, due to the calculation of
"sizeof(*entry) + nr_entries * sizeof(long)", as the sizeof(*entry)
now contains 8 entries.
The size of the caller field needs to be subtracted from the size of
the entry to create the correct allocation size"
* tag 'trace-v5.12-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix stack trace event size
As for bpf_link, refuse creating a non-O_RDWR fd. Since program fds
currently don't allow modifications this is a precaution, not a
straight up bug fix.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210326160501.46234-2-lmb@cloudflare.com
Invoking BPF_OBJ_GET on a pinned bpf_link checks the path access
permissions based on file_flags, but the returned fd ignores flags.
This means that any user can acquire a "read-write" fd for a pinned
link with mode 0664 by invoking BPF_OBJ_GET with BPF_F_RDONLY in
file_flags. The fd can be used to invoke BPF_LINK_DETACH, etc.
Fix this by refusing non-O_RDWR flags in BPF_OBJ_GET. This works
because OBJ_GET by default returns a read write mapping and libbpf
doesn't expose a way to override this behaviour for programs
and links.
Fixes: 70ed506c3b ("bpf: Introduce pinnable bpf_link abstraction")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210326160501.46234-1-lmb@cloudflare.com
On x86 the struct pt_regs * grabbed by task_pt_regs() points to an
offset of task->stack. The pt_regs are later dereferenced in
__bpf_get_stack (e.g. by user_mode() check). This can cause a fault if
the task in question exits while bpf_get_task_stack is executing, as
warned by task_stack_page's comment:
* When accessing the stack of a non-current task that might exit, use
* try_get_task_stack() instead. task_stack_page will return a pointer
* that could get freed out from under you.
Taking the comment's advice and using try_get_task_stack() and
put_task_stack() to hold task->stack refcount, or bail early if it's
already 0. Incrementing stack_refcount will ensure the task's stack
sticks around while we're using its data.
I noticed this bug while testing a bpf task iter similar to
bpf_iter_task_stack in selftests, except mine grabbed user stack, and
getting intermittent crashes, which resulted in dumps like:
BUG: unable to handle page fault for address: 0000000000003fe0
\#PF: supervisor read access in kernel mode
\#PF: error_code(0x0000) - not-present page
RIP: 0010:__bpf_get_stack+0xd0/0x230
<snip...>
Call Trace:
bpf_prog_0a2be35c092cb190_get_task_stacks+0x5d/0x3ec
bpf_iter_run_prog+0x24/0x81
__task_seq_show+0x58/0x80
bpf_seq_read+0xf7/0x3d0
vfs_read+0x91/0x140
ksys_read+0x59/0xd0
do_syscall_64+0x48/0x120
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: fa28dcb82a ("bpf: Introduce helper bpf_get_task_stack()")
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210401000747.3648767-1-davemarchevsky@fb.com
Commit cbc3b92ce0 fixed an issue to modify the macros of the stack trace
event so that user space could parse it properly. Originally the stack
trace format to user space showed that the called stack was a dynamic
array. But it is not actually a dynamic array, in the way that other
dynamic event arrays worked, and this broke user space parsing for it. The
update was to make the array look to have 8 entries in it. Helper
functions were added to make it parse it correctly, as the stack was
dynamic, but was determined by the size of the event stored.
Although this fixed user space on how it read the event, it changed the
internal structure used for the stack trace event. It changed the array
size from [0] to [8] (added 8 entries). This increased the size of the
stack trace event by 8 words. The size reserved on the ring buffer was the
size of the stack trace event plus the number of stack entries found in
the stack trace. That commit caused the amount to be 8 more than what was
needed because it did not expect the caller field to have any size. This
produced 8 entries of garbage (and reading random data) from the stack
trace event:
<idle>-0 [002] d... 1976396.837549: <stack trace>
=> trace_event_raw_event_sched_switch
=> __traceiter_sched_switch
=> __schedule
=> schedule_idle
=> do_idle
=> cpu_startup_entry
=> secondary_startup_64_no_verify
=> 0xc8c5e150ffff93de
=> 0xffff93de
=> 0
=> 0
=> 0xc8c5e17800000000
=> 0x1f30affff93de
=> 0x00000004
=> 0x200000000
Instead, subtract the size of the caller field from the size of the event
to make sure that only the amount needed to store the stack trace is
reserved.
Link: https://lore.kernel.org/lkml/your-ad-here.call-01617191565-ext-9692@work.hours/
Cc: stable@vger.kernel.org
Fixes: cbc3b92ce0 ("tracing: Set kernel_stack's caller size properly")
Reported-by: Vasily Gorbik <gor@linux.ibm.com>
Tested-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reusing BPF_SK_SKB_STREAM_VERDICT is possible but its name is
confusing and more importantly we still want to distinguish them
from user-space. So we can just reuse the stream verdict code but
introduce a new type of eBPF program, skb_verdict. Users are not
allowed to attach stream_verdict and skb_verdict programs to the
same map.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-10-xiyou.wangcong@gmail.com
The function addresses that are traced by ftrace are stored in pages,
and the size is held in a variable. If there's some error in creating
them, the allocate ones will be freed. In this case, it is possible that
the order of pages to be freed may end up being negative due to a size of
zero passed to get_count_order(), and then that negative number will cause
free_pages() to free a very large section. Make sure that does not happen.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCYGR30BQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qnbDAP9yEhTLcDRUi3VLWnEq19Dt4Lsg86Bf
QRpbWG6Ze9EbZQEAgYAOe1fsNCNEIMXXh/4nlKVpKKH+vviS0ux9Z6uhpQQ=
=Veyq
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt:
"Add check of order < 0 before calling free_pages()
The function addresses that are traced by ftrace are stored in pages,
and the size is held in a variable. If there's some error in creating
them, the allocate ones will be freed. In this case, it is possible
that the order of pages to be freed may end up being negative due to a
size of zero passed to get_count_order(), and then that negative
number will cause free_pages() to free a very large section.
Make sure that does not happen"
* tag 'trace-v5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Check if pages were allocated before calling free_pages()
The variable id is being assigned a value that is never read, the
assignment is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210326194348.623782-1-colin.king@canonical.com
It is possible that on error pg->size can be zero when getting its order,
which would return a -1 value. It is dangerous to pass in an order of -1
to free_pages(). Check if order is greater than or equal to zero before
calling free_pages().
Link: https://lore.kernel.org/lkml/20210330093916.432697c7@gandalf.local.home/
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
s/sempahore/semaphore/
s/exacly/exactly/
s/unregistred/unregistered/
s/interation/iteration/
Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
[pmladek@suse.com: Removed 4th hunk. The string has already been removed in the meantime.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210328043932.8310-1-unixbhaskar@gmail.com
The printk code is already hard enough to understand. Remove an
unnecessary indirection by renaming vprintk_func to vprintk (adding
the asmlinkage annotation), and removing the vprintk definition from
printk.c. That way, printk is implemented in terms of vprintk as one
would expect, and there's no "vprintk_func, what's that? Some function
pointer that gets set where?"
The declaration of vprintk in linux/printk.h already has the
__printf(1,0) attribute, there's no point repeating that with the
definition - it's for diagnostics in callers.
linux/printk.h already contains a static inline {return 0;} definition
of vprintk when !CONFIG_PRINTK.
Since the corresponding stub definition of vprintk_func was not marked
"static inline", any translation unit including internal.h would get a
definition of vprintk_func - it just so happens that for
!CONFIG_PRINTK, there is precisely one such TU, namely printk.c. Had
there been more, it would be a link error; now it's just a silly waste
of a few bytes of .text, which one must assume are rather precious to
anyone disabling PRINTK.
$ objdump -dr kernel/printk/printk.o
00000330 <vprintk_func>:
330: 31 c0 xor %eax,%eax
332: c3 ret
333: 8d b4 26 00 00 00 00 lea 0x0(%esi,%eiz,1),%esi
33a: 8d b6 00 00 00 00 lea 0x0(%esi),%esi
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210323144201.486050-1-linux@rasmusvillemoes.dk
The custom devres structure manages only a single pointer which can
can be achieved by using devm_add_action_or_reset() as well which
makes the code simpler.
[ tglx: Fixed return value handling - found by smatch ]
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210301142659.8971-1-brgl@bgdev.pl
Livepatch sends a fake signal to all remaining blocking tasks of a
running transition after a set period of time. It uses TIF_SIGPENDING
flag for the purpose. Commit 12db8b6900 ("entry: Add support for
TIF_NOTIFY_SIGNAL") added a generic infrastructure to achieve the same.
Replace our bespoke solution with the generic one.
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The struct clocksource callbacks enable() and disable() are described as a
way to allow clock sources to enter a power save mode. See commit
4614e6adaf ("clocksource: add enable() and disable() callbacks")
But using runtime PM from these callbacks triggers a cyclic lockdep warning when
switching clock source using change_clocksource().
# echo e60f0000.timer > /sys/devices/system/clocksource/clocksource0/current_clocksource
======================================================
WARNING: possible circular locking dependency detected
------------------------------------------------------
migration/0/11 is trying to acquire lock:
ffff0000403ed220 (&dev->power.lock){-...}-{2:2}, at: __pm_runtime_resume+0x40/0x74
but task is already holding lock:
ffff8000113c8f88 (tk_core.seq.seqcount){----}-{0:0}, at: multi_cpu_stop+0xa4/0x190
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (tk_core.seq.seqcount){----}-{0:0}:
ktime_get+0x28/0xa0
hrtimer_start_range_ns+0x210/0x2dc
generic_sched_clock_init+0x70/0x88
sched_clock_init+0x40/0x64
start_kernel+0x494/0x524
-> #1 (hrtimer_bases.lock){-.-.}-{2:2}:
hrtimer_start_range_ns+0x68/0x2dc
rpm_suspend+0x308/0x5dc
rpm_idle+0xc4/0x2a4
pm_runtime_work+0x98/0xc0
process_one_work+0x294/0x6f0
worker_thread+0x70/0x45c
kthread+0x154/0x160
ret_from_fork+0x10/0x20
-> #0 (&dev->power.lock){-...}-{2:2}:
_raw_spin_lock_irqsave+0x7c/0xc4
__pm_runtime_resume+0x40/0x74
sh_cmt_start+0x1c4/0x260
sh_cmt_clocksource_enable+0x28/0x50
change_clocksource+0x9c/0x160
multi_cpu_stop+0xa4/0x190
cpu_stopper_thread+0x90/0x154
smpboot_thread_fn+0x244/0x270
kthread+0x154/0x160
ret_from_fork+0x10/0x20
other info that might help us debug this:
Chain exists of:
&dev->power.lock --> hrtimer_bases.lock --> tk_core.seq.seqcount
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(tk_core.seq.seqcount);
lock(hrtimer_bases.lock);
lock(tk_core.seq.seqcount);
lock(&dev->power.lock);
*** DEADLOCK ***
2 locks held by migration/0/11:
#0: ffff8000113c9278 (timekeeper_lock){-.-.}-{2:2}, at: change_clocksource+0x2c/0x160
#1: ffff8000113c8f88 (tk_core.seq.seqcount){----}-{0:0}, at: multi_cpu_stop+0xa4/0x190
Rework change_clocksource() so it enables the new clocksource and disables
the old clocksource outside of the timekeeper_lock and seqcount write held
region. There is no requirement that these callbacks are invoked from the
lock held region.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20210211134318.323910-1-niklas.soderlund+renesas@ragnatech.se
The signal handling in __rt_mutex_slowlock() is open coded.
Use signal_pending_state() instead.
Aside of the cleanup this also prepares for the RT lock substituions which
require support for TASK_KILLABLE.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153944.533811987@linutronix.de
The warning as written is expensive and not really required for a
production kernel. Make it depend on rt mutex debugging and use !in_task()
for the condition which generates far better code and gives the same
answer.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153944.436565064@linutronix.de
Preemption is disabled in mark_wakeup_next_waiter(,) not in
rt_mutex_slowunlock().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153944.341734608@linutronix.de
The indirection via a function pointer (which is at least optimized into a
tail call by the compiler) is making the code hard to read.
Clean it up and move the futex related trylock functions down to the futex
section.
Move the wake_q wakeup into rt_mutex_slowunlock(). No point in handing it
to the caller. The futex code uses a different function.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153944.247927548@linutronix.de
rtmutex is half __sched and the other half is not. If the compiler decides
to not inline larger static functions then part of the code ends up in the
regular text section.
There are also quite some performance related small helpers which are
either static or plain inline. Force inline those which make sense and mark
the rest __sched.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153944.152977820@linutronix.de
There is no value in having two header files providing just empty stubs and
a C file which implements trivial debug functions which can just be inlined.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153944.052454464@linutronix.de
The conditional debug handling is just another layer of obfuscation. Split
the function so rt_mutex_init_proxy_locked() can invoke the inner init and
__rt_mutex_init() gets the full treatment.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.955697588@linutronix.de
None of these functions are used when CONFIG_RT_MUTEXES=n.
Remove the gunk. Remove pointless comments and clean up the coding style
mess while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.863379182@linutronix.de
There is no point for this wrapper at all.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.754254046@linutronix.de
No users or useless and therefore just ballast.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.549192485@linutronix.de
The rtmutex specific deadlock detector predates lockdep coverage of rtmutex
and since commit f5694788ad ("rt_mutex: Add lockdep annotations") it
contains a lot of redundant functionality:
- lockdep will detect an potential deadlock before rtmutex-debug
has a chance to do so
- the deadlock debugging is restricted to rtmutexes which are not
associated to futexes and have an active waiter, which is covered by
lockdep already
Remove the redundant functionality and move actual deadlock WARN() into the
deadlock code path. The latter needs a seperate cleanup.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.320398604@linutronix.de
The following debug members of 'struct rtmutex' are unused:
- save_state: No users
- file,line: Printed if ::name is NULL. This is only used for non-futex
locks so ::name is never NULL
- magic: Assigned to NULL by rt_mutex_destroy(), no further usage
Remove them along with unused inline and macro leftovers related to
the long gone deadlock tester.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.195064296@linutronix.de
rt_mutex_timed_lock() has no callers since:
c051b21f71 ("rtmutex: Confine deadlock logic to futex")
Remove it.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210326153943.061103415@linutronix.de
-----BEGIN PGP SIGNATURE-----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=mwLC
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.12-2021-03-27' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
- Use thread info versions of flag testing, as discussed last week.
- The series enabling PF_IO_WORKER to just take signals, instead of
needing to special case that they do not in a bunch of places. Ends
up being pretty trivial to do, and then we can revert all the special
casing we're currently doing.
- Kill dead pointer assignment
- Fix hashed part of async work queue trace
- Fix sign extension issue for IORING_OP_PROVIDE_BUFFERS
- Fix a link completion ordering regression in this merge window
- Cancellation fixes
* tag 'io_uring-5.12-2021-03-27' of git://git.kernel.dk/linux-block:
io_uring: remove unsued assignment to pointer io
io_uring: don't cancel extra on files match
io_uring: don't cancel-track common timeouts
io_uring: do post-completion chore on t-out cancel
io_uring: fix timeout cancel return code
Revert "signal: don't allow STOP on PF_IO_WORKER threads"
Revert "kernel: freezer should treat PF_IO_WORKER like PF_KTHREAD for freezing"
Revert "kernel: treat PF_IO_WORKER like PF_KTHREAD for ptrace/signals"
Revert "signal: don't allow sending any signals to PF_IO_WORKER threads"
kernel: stop masking signals in create_io_thread()
io_uring: handle signals for IO threads like a normal thread
kernel: don't call do_exit() for PF_IO_WORKER threads
io_uring: maintain CQE order of a failed link
io-wq: fix race around pending work on teardown
io_uring: do ctx sqd ejection in a clear context
io_uring: fix provide_buffers sign extension
io_uring: don't skip file_end_write() on reissue
io_uring: correct io_queue_async_work() traces
io_uring: don't use {test,clear}_tsk_thread_flag() for current
This reverts commit 4db4b1a0d1.
The IO threads allow and handle SIGSTOP now, so don't special case them
anymore in task_set_jobctl_pending().
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 15b2219fac.
Before IO threads accepted signals, the freezer using take signals to wake
up an IO thread would cause them to loop without any way to clear the
pending signal. That is no longer the case, so stop special casing
PF_IO_WORKER in the freezer.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 6fb8f43ced.
The IO threads do allow signals now, including SIGSTOP, and we can allow
ptrace attach. Attaching won't reveal anything interesting for the IO
threads, but it will allow eg gdb to attach to a task with io_urings
and IO threads without complaining. And once attached, it will allow
the usual introspection into regular threads.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 5be28c8f85.
IO threads now take signals just fine, so there's no reason to limit them
specifically. Revert the change that prevented that from happening.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is racy - move the blocking into when the task is created and
we're marking it as PF_IO_WORKER anyway. The IO threads are now
prepared to handle signals like SIGSTOP as well, so clear that from
the mask to allow proper stopping of IO threads.
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch adds support to BPF verifier to allow bpf program calling
kernel function directly.
The use case included in this set is to allow bpf-tcp-cc to directly
call some tcp-cc helper functions (e.g. "tcp_cong_avoid_ai()"). Those
functions have already been used by some kernel tcp-cc implementations.
This set will also allow the bpf-tcp-cc program to directly call the
kernel tcp-cc implementation, For example, a bpf_dctcp may only want to
implement its own dctcp_cwnd_event() and reuse other dctcp_*() directly
from the kernel tcp_dctcp.c instead of reimplementing (or
copy-and-pasting) them.
The tcp-cc kernel functions mentioned above will be white listed
for the struct_ops bpf-tcp-cc programs to use in a later patch.
The white listed functions are not bounded to a fixed ABI contract.
Those functions have already been used by the existing kernel tcp-cc.
If any of them has changed, both in-tree and out-of-tree kernel tcp-cc
implementations have to be changed. The same goes for the struct_ops
bpf-tcp-cc programs which have to be adjusted accordingly.
This patch is to make the required changes in the bpf verifier.
First change is in btf.c, it adds a case in "btf_check_func_arg_match()".
When the passed in "btf->kernel_btf == true", it means matching the
verifier regs' states with a kernel function. This will handle the
PTR_TO_BTF_ID reg. It also maps PTR_TO_SOCK_COMMON, PTR_TO_SOCKET,
and PTR_TO_TCP_SOCK to its kernel's btf_id.
In the later libbpf patch, the insn calling a kernel function will
look like:
insn->code == (BPF_JMP | BPF_CALL)
insn->src_reg == BPF_PSEUDO_KFUNC_CALL /* <- new in this patch */
insn->imm == func_btf_id /* btf_id of the running kernel */
[ For the future calling function-in-kernel-module support, an array
of module btf_fds can be passed at the load time and insn->off
can be used to index into this array. ]
At the early stage of verifier, the verifier will collect all kernel
function calls into "struct bpf_kfunc_desc". Those
descriptors are stored in "prog->aux->kfunc_tab" and will
be available to the JIT. Since this "add" operation is similar
to the current "add_subprog()" and looking for the same insn->code,
they are done together in the new "add_subprog_and_kfunc()".
In the "do_check()" stage, the new "check_kfunc_call()" is added
to verify the kernel function call instruction:
1. Ensure the kernel function can be used by a particular BPF_PROG_TYPE.
A new bpf_verifier_ops "check_kfunc_call" is added to do that.
The bpf-tcp-cc struct_ops program will implement this function in
a later patch.
2. Call "btf_check_kfunc_args_match()" to ensure the regs can be
used as the args of a kernel function.
3. Mark the regs' type, subreg_def, and zext_dst.
At the later do_misc_fixups() stage, the new fixup_kfunc_call()
will replace the insn->imm with the function address (relative
to __bpf_call_base). If needed, the jit can find the btf_func_model
by calling the new bpf_jit_find_kfunc_model(prog, insn).
With the imm set to the function address, "bpftool prog dump xlated"
will be able to display the kernel function calls the same way as
it displays other bpf helper calls.
gpl_compatible program is required to call kernel function.
This feature currently requires JIT.
The verifier selftests are adjusted because of the changes in
the verbose log in add_subprog_and_kfunc().
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015142.1544736-1-kafai@fb.com
This patch moved the subprog specific logic from
btf_check_func_arg_match() to the new btf_check_subprog_arg_match().
The core logic is left in btf_check_func_arg_match() which
will be reused later to check the kernel function call.
The "if (!btf_type_is_ptr(t))" is checked first to improve the
indentation which will be useful for a later patch.
Some of the "btf_kind_str[]" usages is replaced with the shortcut
"btf_type_str(t)".
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015136.1544504-1-kafai@fb.com
This patch simplifies the linfo freeing logic by combining
"bpf_prog_free_jited_linfo()" and "bpf_prog_free_unused_jited_linfo()"
into the new "bpf_prog_jit_attempt_done()".
It is a prep work for the kernel function call support. In a later
patch, freeing the kernel function call descriptors will also
be done in the "bpf_prog_jit_attempt_done()".
"bpf_prog_free_linfo()" is removed since it is only called by
"__bpf_prog_put_noref()". The kvfree() are directly called
instead.
It also takes this chance to s/kcalloc/kvcalloc/ for the jited_linfo
allocation.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015130.1544323-1-kafai@fb.com
Currently module can be unloaded even if there's a trampoline
register in it. It's easily reproduced by running in parallel:
# while :; do ./test_progs -t module_attach; done
# while :; do rmmod bpf_testmod; sleep 0.5; done
Taking the module reference in case the trampoline's ip is
within the module code. Releasing it when the trampoline's
ip is unregistered.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210326105900.151466-1-jolsa@kernel.org
Right now we're never calling get_signal() from PF_IO_WORKER threads, but
in preparation for doing so, don't handle a fatal signal for them. The
workers have state they need to cleanup when exiting, so just return
instead of calling do_exit() on their behalf. The threads themselves will
detect a fatal signal and do proper shutdown.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- Modify the runtime PM device suspend to avoid suspending
supplier devices before the consumer device's status changes
to RPM_SUSPENDED (Rafael Wysocki).
- Change the Energy Model code to prevent it from attempting to
create its main debugfs directory too early (Lukasz Luba).
-----BEGIN PGP SIGNATURE-----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=9csw
-----END PGP SIGNATURE-----
Merge tag 'pm-5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix an issue related to device links in the runtime PM framework
and debugfs usage in the Energy Model code.
Specifics:
- Modify the runtime PM device suspend to avoid suspending supplier
devices before the consumer device's status changes to
RPM_SUSPENDED (Rafael Wysocki)
- Change the Energy Model code to prevent it from attempting to
create its main debugfs directory too early (Lukasz Luba)"
* tag 'pm-5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: EM: postpone creating the debugfs dir till fs_initcall
PM: runtime: Defer suspending suppliers
The name string for BPF_XOR is "xor", not "or". Fix it.
Fixes: 981f94c3e9 ("bpf: Add bitwise atomic instructions")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Brendan Jackman <jackmanb@google.com>
Link: https://lore.kernel.org/bpf/20210325134141.8533-1-xukuohai@huawei.com
With the introduction of the struct_ops program type, it became possible to
implement kernel functionality in BPF, making it viable to use BPF in place
of a regular kernel module for these particular operations.
Thus far, the only user of this mechanism is for implementing TCP
congestion control algorithms. These are clearly marked as GPL-only when
implemented as modules (as seen by the use of EXPORT_SYMBOL_GPL for
tcp_register_congestion_control()), so it seems like an oversight that this
was not carried over to BPF implementations. Since this is the only user
of the struct_ops mechanism, just enforcing GPL-only for the struct_ops
program type seems like the simplest way to fix this.
Fixes: 0baf26b0fc ("bpf: tcp: Support tcp_congestion_ops in bpf")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210326100314.121853-1-toke@redhat.com
Jiri Olsa reported a bug ([1]) in kernel where cgroup local
storage pointer may be NULL in bpf_get_local_storage() helper.
There are two issues uncovered by this bug:
(1). kprobe or tracepoint prog incorrectly sets cgroup local storage
before prog run,
(2). due to change from preempt_disable to migrate_disable,
preemption is possible and percpu storage might be overwritten
by other tasks.
This issue (1) is fixed in [2]. This patch tried to address issue (2).
The following shows how things can go wrong:
task 1: bpf_cgroup_storage_set() for percpu local storage
preemption happens
task 2: bpf_cgroup_storage_set() for percpu local storage
preemption happens
task 1: run bpf program
task 1 will effectively use the percpu local storage setting by task 2
which will be either NULL or incorrect ones.
Instead of just one common local storage per cpu, this patch fixed
the issue by permitting 8 local storages per cpu and each local
storage is identified by a task_struct pointer. This way, we
allow at most 8 nested preemption between bpf_cgroup_storage_set()
and bpf_cgroup_storage_unset(). The percpu local storage slot
is released (calling bpf_cgroup_storage_unset()) by the same task
after bpf program finished running.
bpf_test_run() is also fixed to use the new bpf_cgroup_storage_set()
interface.
The patch is tested on top of [2] with reproducer in [1].
Without this patch, kernel will emit error in 2-3 minutes.
With this patch, after one hour, still no error.
[1] https://lore.kernel.org/bpf/CAKH8qBuXCfUz=w8L+Fj74OaUpbosO29niYwTki7e3Ag044_aww@mail.gmail.com/T
[2] https://lore.kernel.org/bpf/20210309185028.3763817-1-yhs@fb.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Link: https://lore.kernel.org/bpf/20210323055146.3334476-1-yhs@fb.com
Networking has many sysctls that could fit in one u8.
This patch adds proc_dou8vec_minmax() for this purpose.
Note that the .extra1 and .extra2 fields are pointing
to integers, because it makes conversions easier.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove PTR_TO_MAP_KEY for the time being from being sanitized on pointer ALU
through sanitize_ptr_alu() mainly for 3 reasons:
1) It's currently unused and not available from unprivileged. However that by
itself is not yet a strong reason to drop the code.
2) Commit 69c087ba62 ("bpf: Add bpf_for_each_map_elem() helper") implemented
the sanitation not fully correct in that unlike stack or map_value pointer
it doesn't probe whether the access to the map key /after/ the simulated ALU
operation is still in bounds. This means that the generated mask can truncate
the offset in the non-speculative domain whereas it should only truncate in
the speculative domain. The verifier should instead reject such program as
we do for other types.
3) Given the recent fixes from f232326f69 ("bpf: Prohibit alu ops for pointer
types not defining ptr_limit"), 10d2bb2e6b ("bpf: Fix off-by-one for area
size in creating mask to left"), b5871dca25 ("bpf: Simplify alu_limit masking
for pointer arithmetic") as well as 1b1597e64e ("bpf: Add sanity check for
upper ptr_limit") the code changed quite a bit and the merge in efd13b71a3
broke the PTR_TO_MAP_KEY case due to an incorrect merge conflict.
Remove the relevant pieces for the time being and we can rework the PTR_TO_MAP_KEY
case once everything settles.
Fixes: efd13b71a3 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")
Fixes: 69c087ba62 ("bpf: Add bpf_for_each_map_elem() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-03-24
The following pull-request contains BPF updates for your *net-next* tree.
We've added 37 non-merge commits during the last 15 day(s) which contain
a total of 65 files changed, 3200 insertions(+), 738 deletions(-).
The main changes are:
1) Static linking of multiple BPF ELF files, from Andrii.
2) Move drop error path to devmap for XDP_REDIRECT, from Lorenzo.
3) Spelling fixes from various folks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge misc fixes from Andrew Morton:
"14 patches.
Subsystems affected by this patch series: mm (hugetlb, kasan, gup,
selftests, z3fold, kfence, memblock, and highmem), squashfs, ia64,
gcov, and mailmap"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mailmap: update Andrey Konovalov's email address
mm/highmem: fix CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
mm: memblock: fix section mismatch warning again
kfence: make compatible with kmemleak
gcov: fix clang-11+ support
ia64: fix format strings for err_inject
ia64: mca: allocate early mca with GFP_ATOMIC
squashfs: fix xattr id and id lookup sanity checks
squashfs: fix inode lookup sanity checks
z3fold: prevent reclaim/free race for headless pages
selftests/vm: fix out-of-tree build
mm/mmu_notifiers: ensure range_end() is paired with range_start()
kasan: fix per-page tags for non-page_alloc pages
hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings
LLVM changed the expected function signatures for llvm_gcda_start_file()
and llvm_gcda_emit_function() in the clang-11 release. Users of
clang-11 or newer may have noticed their kernels failing to boot due to
a panic when enabling CONFIG_GCOV_KERNEL=y +CONFIG_GCOV_PROFILE_ALL=y.
Fix up the function signatures so calling these functions doesn't panic
the kernel.
Link: https://reviews.llvm.org/rGcdd683b516d147925212724b09ec6fb792a40041
Link: https://reviews.llvm.org/rG13a633b438b6500ecad9e4f936ebadf3411d0f44
Link: https://lkml.kernel.org/r/20210312224132.3413602-2-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Prasad Sodagudi <psodagud@quicinc.com>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Cc: <stable@vger.kernel.org> [5.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mask is built in build_balance_mask() by for_each_cpu(i, sg_span), so
it must be a subset of sched_group_span(sg).
So the cpumask_and() call is redundant - remove it.
[ mingo: Adjusted the changelog a bit. ]
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Valentin Schneider <Valentin.Schneider@arm.com>
Link: https://lore.kernel.org/r/20210325023140.23456-1-song.bao.hua@hisilicon.com
-1 is -EPERM which is a somewhat odd error to return from
sched_dynamic_write(). No other callers care about which negative
value is used.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20210325004515.531631-2-linux@rasmusvillemoes.dk
Use the enum names which are also what is used in the switch() in
sched_dynamic_update().
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20210325004515.531631-1-linux@rasmusvillemoes.dk
Pull networking fixes from David Miller:
"Various fixes, all over:
1) Fix overflow in ptp_qoriq_adjfine(), from Yangbo Lu.
2) Always store the rx queue mapping in veth, from Maciej
Fijalkowski.
3) Don't allow vmlinux btf in map_create, from Alexei Starovoitov.
4) Fix memory leak in octeontx2-af from Colin Ian King.
5) Use kvalloc in bpf x86 JIT for storing jit'd addresses, from
Yonghong Song.
6) Fix tx ptp stats in mlx5, from Aya Levin.
7) Check correct ip version in tun decap, fropm Roi Dayan.
8) Fix rate calculation in mlx5 E-Switch code, from arav Pandit.
9) Work item memork leak in mlx5, from Shay Drory.
10) Fix ip6ip6 tunnel crash with bpf, from Daniel Borkmann.
11) Lack of preemptrion awareness in macvlan, from Eric Dumazet.
12) Fix data race in pxa168_eth, from Pavel Andrianov.
13) Range validate stab in red_check_params(), from Eric Dumazet.
14) Inherit vlan filtering setting properly in b53 driver, from
Florian Fainelli.
15) Fix rtnl locking in igc driver, from Sasha Neftin.
16) Pause handling fixes in igc driver, from Muhammad Husaini
Zulkifli.
17) Missing rtnl locking in e1000_reset_task, from Vitaly Lifshits.
18) Use after free in qlcnic, from Lv Yunlong.
19) fix crash in fritzpci mISDN, from Tong Zhang.
20) Premature rx buffer reuse in igb, from Li RongQing.
21) Missing termination of ip[a driver message handler arrays, from
Alex Elder.
22) Fix race between "x25_close" and "x25_xmit"/"x25_rx" in hdlc_x25
driver, from Xie He.
23) Use after free in c_can_pci_remove(), from Tong Zhang.
24) Uninitialized variable use in nl80211, from Jarod Wilson.
25) Off by one size calc in bpf verifier, from Piotr Krysiuk.
26) Use delayed work instead of deferrable for flowtable GC, from
Yinjun Zhang.
27) Fix infinite loop in NPC unmap of octeontx2 driver, from
Hariprasad Kelam.
28) Fix being unable to change MTU of dwmac-sun8i devices due to lack
of fifo sizes, from Corentin Labbe.
29) DMA use after free in r8169 with WoL, fom Heiner Kallweit.
30) Mismatched prototypes in isdn-capi, from Arnd Bergmann.
31) Fix psample UAPI breakage, from Ido Schimmel"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (171 commits)
psample: Fix user API breakage
math: Export mul_u64_u64_div_u64
ch_ktls: fix enum-conversion warning
octeontx2-af: Fix memory leak of object buf
ptp_qoriq: fix overflow in ptp_qoriq_adjfine() u64 calcalation
net: bridge: don't notify switchdev for local FDB addresses
net/sched: act_ct: clear post_ct if doing ct_clear
net: dsa: don't assign an error value to tag_ops
isdn: capi: fix mismatched prototypes
net/mlx5: SF, do not use ecpu bit for vhca state processing
net/mlx5e: Fix division by 0 in mlx5e_select_queue
net/mlx5e: Fix error path for ethtool set-priv-flag
net/mlx5e: Offload tuple rewrite for non-CT flows
net/mlx5e: Allow to match on MPLS parameters only for MPLS over UDP
net/mlx5: Add back multicast stats for uplink representor
net: ipconfig: ic_dev can be NULL in ic_close_devs
MAINTAINERS: Combine "QLOGIC QLGE 10Gb ETHERNET DRIVER" sections into one
docs: networking: Fix a typo
r8169: fix DMA being used after buffer free if WoL is enabled
net: ipa: fix init header command validation
...
This commit causes rcutorture to test the new start_poll_synchronize_rcu()
and poll_state_synchronize_rcu() functions. Because of the difficulty of
determining the nature of a synchronous RCU grace (expedited or not),
the test that insisted that poll_state_synchronize_rcu() detect an
intervening synchronize_rcu() had to be dropped.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
There is a need for a non-blocking polling interface for RCU grace
periods, so this commit supplies start_poll_synchronize_rcu() and
poll_state_synchronize_rcu() for this purpose. Note that the existing
get_state_synchronize_rcu() may be used if future grace periods are
inevitable (perhaps due to a later call_rcu() invocation). The new
start_poll_synchronize_rcu() is to be used if future grace periods
might not otherwise happen. Finally, poll_state_synchronize_rcu()
provides a lockless check for a grace period having elapsed since
the corresponding call to either of the get_state_synchronize_rcu()
or start_poll_synchronize_rcu().
As with get_state_synchronize_rcu(), the return value from either
get_state_synchronize_rcu() or start_poll_synchronize_rcu() is passed in
to a later call to either poll_state_synchronize_rcu() or the existing
(might_sleep) cond_synchronize_rcu().
[ paulmck: Revert cond_synchronize_rcu() to might_sleep() per Frederic Weisbecker feedback. ]
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
gcc -Wextra wants type modifiers in the normal order:
kernel/bpf/bpf_lsm.c:70:1: error: 'static' is not at beginning of declaration [-Werror=old-style-declaration]
70 | const static struct bpf_func_proto bpf_bprm_opts_set_proto = {
| ^~~~~
kernel/bpf/bpf_lsm.c:91:1: error: 'static' is not at beginning of declaration [-Werror=old-style-declaration]
91 | const static struct bpf_func_proto bpf_ima_inode_hash_proto = {
| ^~~~~
Fixes: 3f6719c7b6 ("bpf: Add bpf_bprm_opts_set helper")
Fixes: 27672f0d28 ("bpf: Add a BPF helper for getting the IMA hash of an inode")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210322215201.1097281-1-arnd@kernel.org
gcc warns about an empty statement when audit_remove_mark is defined to
nothing:
kernel/auditfilter.c: In function 'audit_data_to_entry':
kernel/auditfilter.c:609:51: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
609 | audit_remove_mark(entry->rule.exe); /* that's the template one */
| ^
Change the macros to use the usual "do { } while (0)" instead, and change a
few more that were (void)0, for consistency.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The debugfs directory '/sys/kernel/debug/energy_model' is needed before
the Energy Model registration can happen. With the recent change in
debugfs subsystem it's not allowed to create this directory at early
stage (core_initcall). Thus creating this directory would fail.
Postpone the creation of the EM debug dir to later stage: fs_initcall.
It should be safe since all clients: CPUFreq drivers, Devfreq drivers
will be initialized in later stages.
The custom debug log below prints the time of creation the EM debug dir
at fs_initcall and successful registration of EMs at later stages.
[ 1.505717] energy_model: creating rootdir
[ 3.698307] cpu cpu0: EM: created perf domain
[ 3.709022] cpu cpu1: EM: created perf domain
Fixes: 56348560d4 ("debugfs: do not attempt to create a new file before the filesystem is initalized")
Reported-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
A long-tail load balance cost is observed on the newly idle path,
this is caused by a race window between the first nr_running check
of the busiest runqueue and its nr_running recheck in detach_tasks.
Before the busiest runqueue is locked, the tasks on the busiest
runqueue could be pulled by other CPUs and nr_running of the busiest
runqueu becomes 1 or even 0 if the running task becomes idle, this
causes detach_tasks breaks with LBF_ALL_PINNED flag set, and triggers
load_balance redo at the same sched_domain level.
In order to find the new busiest sched_group and CPU, load balance will
recompute and update the various load statistics, which eventually leads
to the long-tail load balance cost.
This patch clears LBF_ALL_PINNED flag for this race condition, and hence
reduces the long-tail cost of newly idle balance.
Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/1614154549-116078-1-git-send-email-aubrey.li@intel.com
update_idle_core() is only done for the case of sched_smt_present.
but test_idle_cores() is done for all machines even those without
SMT.
This can contribute to up 8%+ hackbench performance loss on a
machine like kunpeng 920 which has no SMT. This patch removes the
redundant test_idle_cores() for !SMT machines.
Hackbench is ran with -g {2..14}, for each g it is ran 10 times to get
an average.
$ numactl -N 0 hackbench -p -T -l 20000 -g $1
The below is the result of hackbench w/ and w/o this patch:
g= 2 4 6 8 10 12 14
w/o: 1.8151 3.8499 5.5142 7.2491 9.0340 10.7345 12.0929
w/ : 1.8428 3.7436 5.4501 6.9522 8.2882 9.9535 11.3367
+4.1% +8.3% +7.3% +6.3%
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/20210320221432.924-1-song.bao.hua@hisilicon.com
We noticed that the cost of psi increases with the increase in the
levels of the cgroups. Particularly the cost of cpu_clock() sticks out
as the kernel calls it multiple times as it traverses up the cgroup
tree. This patch reduces the calls to cpu_clock().
Performed perf bench on Intel Broadwell with 3 levels of cgroup.
Before the patch:
$ perf bench sched all
# Running sched/messaging benchmark...
# 20 sender and receiver processes per group
# 10 groups == 400 processes run
Total time: 0.747 [sec]
# Running sched/pipe benchmark...
# Executed 1000000 pipe operations between two processes
Total time: 3.516 [sec]
3.516689 usecs/op
284358 ops/sec
After the patch:
$ perf bench sched all
# Running sched/messaging benchmark...
# 20 sender and receiver processes per group
# 10 groups == 400 processes run
Total time: 0.640 [sec]
# Running sched/pipe benchmark...
# Executed 1000000 pipe operations between two processes
Total time: 3.329 [sec]
3.329820 usecs/op
300316 ops/sec
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/20210321205156.4186483-1-shakeelb@google.com
Most callsites were covered by commit
a8b62fd085 ("stop_machine: Add function and caller debug info")
but this skipped queue_stop_cpus_work(). Add caller debug info to it.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201210163830.21514-2-valentin.schneider@arm.com
Clang doesn't like format strings that truncate a 32-bit
value to something shorter:
kernel/locking/lockdep.c:709:4: error: format specifies type 'short' but the argument has type 'int' [-Werror,-Wformat]
In this case, the warning is a slightly questionable, as it could realize
that both class->wait_type_outer and class->wait_type_inner are in fact
8-bit struct members, even though the result of the ?: operator becomes an
'int'.
However, there is really no point in printing the number as a 16-bit
'short' rather than either an 8-bit or 32-bit number, so just change
it to a normal %d.
Fixes: de8f5e4f2d ("lockdep: Introduce wait-type checks")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210322115531.3987555-1-arnd@kernel.org
Of the three LSMs that implement the security_task_getsecid() LSM
hook, all three LSMs provide the task's objective security
credentials. This turns out to be unfortunate as most of the hook's
callers seem to expect the task's subjective credentials, although
a small handful of callers do correctly expect the objective
credentials.
This patch is the first step towards fixing the problem: it splits
the existing security_task_getsecid() hook into two variants, one
for the subjective creds, one for the objective creds.
void security_task_getsecid_subj(struct task_struct *p,
u32 *secid);
void security_task_getsecid_obj(struct task_struct *p,
u32 *secid);
While this patch does fix all of the callers to use the correct
variant, in order to keep this patch focused on the callers and to
ease review, the LSMs continue to use the same implementation for
both hooks. The net effect is that this patch should not change
the behavior of the kernel in any way, it will be up to the latter
LSM specific patches in this series to change the hook
implementations and return the correct credentials.
Acked-by: Mimi Zohar <zohar@linux.ibm.com> (IMA)
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
There is a need for a non-blocking polling interface for RCU grace
periods, so this commit supplies start_poll_synchronize_rcu() and
poll_state_synchronize_rcu() for this purpose. Note that the existing
get_state_synchronize_rcu() may be used if future grace periods are
inevitable (perhaps due to a later call_rcu() invocation). The new
start_poll_synchronize_rcu() is to be used if future grace periods
might not otherwise happen. Finally, poll_state_synchronize_rcu()
provides a lockless check for a grace period having elapsed since
the corresponding call to either of the get_state_synchronize_rcu()
or start_poll_synchronize_rcu().
As with get_state_synchronize_rcu(), the return value from either
get_state_synchronize_rcu() or start_poll_synchronize_rcu() is passed in
to a later call to either poll_state_synchronize_rcu() or the existing
(might_sleep) cond_synchronize_rcu().
[ paulmck: Remove redundant smp_mb() per Frederic Weisbecker feedback. ]
[ Update poll_state_synchronize_rcu() docbook per Frederic Weisbecker feedback. ]
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The Frequency Invariance Engine (FIE) is providing a frequency scaling
correction factor that helps achieve more accurate load-tracking.
Normally, this scaling factor can be obtained directly with the help of
the cpufreq drivers as they know the exact frequency the hardware is
running at. But that isn't the case for CPPC cpufreq driver.
Another way of obtaining that is using the arch specific counter
support, which is already present in kernel, but that hardware is
optional for platforms.
This patch updates the CPPC driver to register itself with the topology
core to provide its own implementation (cppc_scale_freq_tick()) of
topology_scale_freq_tick() which gets called by the scheduler on every
tick. Note that the arch specific counters have higher priority than
CPPC counters, if available, though the CPPC driver doesn't need to have
any special handling for that.
On an invocation of cppc_scale_freq_tick(), we schedule an irq work
(since we reach here from hard-irq context), which then schedules a
normal work item and cppc_scale_freq_workfn() updates the per_cpu
arch_freq_scale variable based on the counter updates since the last
tick.
To allow platforms to disable this CPPC counter-based frequency
invariance support, this is all done under CONFIG_ACPI_CPPC_CPUFREQ_FIE,
which is enabled by default.
This also exports sched_setattr_nocheck() as the CPPC driver can be
built as a module.
Cc: linux-acpi@vger.kernel.org
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Fix ~42 single-word typos in scheduler code comments.
We have accumulated a few fun ones over the years. :-)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: linux-kernel@vger.kernel.org
-----BEGIN PGP SIGNATURE-----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=xaEf
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.12-2021-03-21' of git://git.kernel.dk/linux-block
Pull io_uring followup fixes from Jens Axboe:
- The SIGSTOP change from Eric, so we properly ignore that for
PF_IO_WORKER threads.
- Disallow sending signals to PF_IO_WORKER threads in general, we're
not interested in having them funnel back to the io_uring owning
task.
- Stable fix from Stefan, ensuring we properly break links for short
send/sendmsg recv/recvmsg if MSG_WAITALL is set.
- Catch and loop when needing to run task_work before a PF_IO_WORKER
threads goes to sleep.
* tag 'io_uring-5.12-2021-03-21' of git://git.kernel.dk/linux-block:
io_uring: call req_set_fail_links() on short send[msg]()/recv[msg]() with MSG_WAITALL
io-wq: ensure task is running before processing task_work
signal: don't allow STOP on PF_IO_WORKER threads
signal: don't allow sending any signals to PF_IO_WORKER threads
plus a DocBook fix.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=IkEX
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Ingo Molnar:
"A change to robustify force-threaded IRQ handlers to always disable
interrupts, plus a DocBook fix.
The force-threaded IRQ handler change has been accelerated from the
normal schedule of such a change to keep the bad pattern/workaround of
spin_lock_irqsave() in handlers or IRQF_NOTHREAD as a kludge from
spreading"
* tag 'irq-urgent-2021-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Disable interrupts for force threaded handlers
genirq/irq_sim: Fix typos in kernel doc (fnode -> fwnode)
devicetree-node lookups.
- Restore the IRQ2 ignore logic
- Fix get_nr_restart_syscall() to return the correct restart syscall number.
Split in a 4-patches set to avoid kABI breakage when backporting to dead
kernels.
-----BEGIN PGP SIGNATURE-----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=WfC4
-----END PGP SIGNATURE-----
Merge tag 'x86_urgent_for_v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
"The freshest pile of shiny x86 fixes for 5.12:
- Add the arch-specific mapping between physical and logical CPUs to
fix devicetree-node lookups
- Restore the IRQ2 ignore logic
- Fix get_nr_restart_syscall() to return the correct restart syscall
number. Split in a 4-patches set to avoid kABI breakage when
backporting to dead kernels"
* tag 'x86_urgent_for_v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic/of: Fix CPU devicetree-node lookups
x86/ioapic: Ignore IRQ2 again
x86: Introduce restart_block->arch_data to remove TS_COMPAT_RESTART
x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall()
x86: Move TS_COMPAT back to asm/thread_info.h
kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data()
Just like we don't allow normal signals to IO threads, don't deliver a
STOP to a task that has PF_IO_WORKER set. The IO threads don't take
signals in general, and have no means of flushing out a stop either.
Longer term, we may want to look into allowing stop of these threads,
as it relates to eg process freezing. For now, this prevents a spin
issue if a SIGSTOP is delivered to the parent task.
Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
They don't take signals individually, and even if they share signals with
the parent task, don't allow them to be delivered through the worker
thread. Linux does allow this kind of behavior for regular threads, but
it's really a compatability thing that we need not care about for the IO
threads.
Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since this message is printed when dynamically allocated spinlocks (e.g.
kzalloc()) are used without initialization (e.g. spin_lock_init()),
suggest to developers to check whether initialization functions for objects
were called, before making developers wonder what annotation is missing.
[ mingo: Minor tweaks to the message. ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210321064913.4619-1-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With interrupt force threading all device interrupt handlers are invoked
from kernel threads. Contrary to hard interrupt context the invocation only
disables bottom halfs, but not interrupts. This was an oversight back then
because any code like this will have an issue:
thread(irq_A)
irq_handler(A)
spin_lock(&foo->lock);
interrupt(irq_B)
irq_handler(B)
spin_lock(&foo->lock);
This has been triggered with networking (NAPI vs. hrtimers) and console
drivers where printk() happens from an interrupt which interrupted the
force threaded handler.
Now people noticed and started to change the spin_lock() in the handler to
spin_lock_irqsave() which affects performance or add IRQF_NOTHREAD to the
interrupt request which in turn breaks RT.
Fix the root cause and not the symptom and disable interrupts before
invoking the force threaded handler which preserves the regular semantics
and the usefulness of the interrupt force threading as a general debugging
tool.
For not RT this is not changing much, except that during the execution of
the threaded handler interrupts are delayed until the handler
returns. Vs. scheduling and softirq processing there is no difference.
For RT kernels there is no issue.
Fixes: 8d32a307e4 ("genirq: Provide forced interrupt threading")
Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Johan Hovold <johan@kernel.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20210317143859.513307808@linutronix.de
-----BEGIN PGP SIGNATURE-----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=aPxz
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.12-2021-03-19' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
"Quieter week this time, which was both expected and desired. About
half of the below is fixes for this release, the other half are just
fixes in general. In detail:
- Fix the freezing of IO threads, by making the freezer not send them
fake signals. Make them freezable by default.
- Like we did for personalities, move the buffer IDR to xarray. Kills
some code and avoids a use-after-free on teardown.
- SQPOLL cleanups and fixes (Pavel)
- Fix linked timeout race (Pavel)
- Fix potential completion post use-after-free (Pavel)
- Cleanup and move internal structures outside of general kernel view
(Stefan)
- Use MSG_SIGNAL for send/recv from io_uring (Stefan)"
* tag 'io_uring-5.12-2021-03-19' of git://git.kernel.dk/linux-block:
io_uring: don't leak creds on SQO attach error
io_uring: use typesafe pointers in io_uring_task
io_uring: remove structures from include/linux/io_uring.h
io_uring: imply MSG_NOSIGNAL for send[msg]()/recv[msg]() calls
io_uring: fix sqpoll cancellation via task_work
io_uring: add generic callback_head helpers
io_uring: fix concurrent parking
io_uring: halt SQO submission on ctx exit
io_uring: replace sqd rw_semaphore with mutex
io_uring: fix complete_post use ctx after free
io_uring: fix ->flags races by linked timeouts
io_uring: convert io_buffer_idr to XArray
io_uring: allow IO worker threads to be frozen
kernel: freezer should treat PF_IO_WORKER like PF_KTHREAD for freezing
Two insn_buf[16] variables are declared in the function which acts on
function scope and block scope respectively. The statement in the inner
block is redundant, so remove it.
Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210318024851.49693-1-Jianlin.Lv@arm.com
Wang Wensheng