Merge tag 'v6.6.51' into for/openbmc/dev-6.6

This is the 6.6.51 stable release

smp: Add missing destroy_work_on_stack() call in smp_call_on_cpu()

[ Upstream commit 77aeb1b685f9db73d276bad4bb30d48505a6fd23 ]

For CONFIG_DEBUG_OBJECTS_WORK=y kernels sscs.work defined by
INIT_WOR

smp: Add missing destroy_work_on_stack() call in smp_call_on_cpu()

[ Upstream commit 77aeb1b685f9db73d276bad4bb30d48505a6fd23 ]

For CONFIG_DEBUG_OBJECTS_WORK=y kernels sscs.work defined by
INIT_WORK_ONSTACK() is initialized by debug_object_init_on_stack() for
the debug check in __init_work() to work correctly.

But this lacks the counterpart to remove the tracked object from debug
objects again, which will cause a debug object warning once the stack is
freed.

Add the missing destroy_work_on_stack() invocation to cure that.

[ tglx: Massaged changelog ]

Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20240704065213.13559-1-qiang.zhang1211@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Merge tag 'v6.6.6' into dev-6.6

This is the 6.6.6 stable release

Signed-off-by: Joel Stanley <joel@jms.id.au>

smp,csd: Throw an error if a CSD lock is stuck for too long

[ Upstream commit 94b3f0b5af2c7af69e3d6e0cdd9b0ea535f22186 ]

The CSD lock seems to get stuck in 2 "modes". When it gets stuck
temporarily

smp,csd: Throw an error if a CSD lock is stuck for too long

[ Upstream commit 94b3f0b5af2c7af69e3d6e0cdd9b0ea535f22186 ]

The CSD lock seems to get stuck in 2 "modes". When it gets stuck
temporarily, it usually gets released in a few seconds, and sometimes
up to one or two minutes.

If the CSD lock stays stuck for more than several minutes, it never
seems to get unstuck, and gradually more and more things in the system
end up also getting stuck.

In the latter case, we should just give up, so the system can dump out
a little more information about what went wrong, and, with panic_on_oops
and a kdump kernel loaded, dump a whole bunch more information about what
might have gone wrong. In addition, there is an smp.panic_on_ipistall
kernel boot parameter that by default retains the old behavior, but when
set enables the panic after the CSD lock has been stuck for more than
the specified number of milliseconds, as in 300,000 for five minutes.

[ paulmck: Apply Imran Khan feedback. ]
[ paulmck: Apply Leonardo Bras feedback. ]

Link: https://lore.kernel.org/lkml/bc7cc8b0-f587-4451-8bcd-0daae627bcc7@paulmck-laptop/
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Imran Khan <imran.f.khan@oracle.com>
Reviewed-by: Leonardo Bras <leobras@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.

Merge tag 'csd-lock.2023.07.15a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull CSD lock updates from Paul McKenney:
"This series reduces the number of stack traces dumped

Merge tag 'csd-lock.2023.07.15a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull CSD lock updates from Paul McKenney:
"This series reduces the number of stack traces dumped during CSD-lock
debugging. This helps to avoid console overrun on systems with large
numbers of CPUs"

* tag 'csd-lock.2023.07.15a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
smp: Reduce NMI traffic from CSD waiters to CSD destination
smp: Reduce logging due to dump_stack of CSD waiters

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Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo V

Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

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Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/1

Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/121735/

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

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Merge drm/drm-next into drm-misc-next

Backmerging to get v6.5-rc2.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'v6.4' into next

Sync up with mainline to bring in updates to shared infrastructure.

ASoC: Merge v6.5-rc2

Get a similar baseline to my other branches, and fixes for people using
the branch.

Merge v6.5-rc1 into drm-misc-fixes

Boris needs 6.5-rc1 in drm-misc-fixes to prevent a conflict.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

smp: Reduce NMI traffic from CSD waiters to CSD destination

On systems with hundreds of CPUs, if most of the CPUs detect a CSD hang,
then all of these waiting CPUs send an NMI to the destination CPU

smp: Reduce NMI traffic from CSD waiters to CSD destination

On systems with hundreds of CPUs, if most of the CPUs detect a CSD hang,
then all of these waiting CPUs send an NMI to the destination CPU in
order to dump its backtrace.

Given enough NMIs, the destination CPU will spent much of its time
producing backtraces, thus further delaying that CPU's response to the
original CSD IPI. In the worst case, by the time destination CPU is
done producing all of these backtrace NMIs, the CSD wait timeout will
have elapsed so that the waiters resend their backtrace NMIs again,
further delaying forward progress.

Therefore, to avoid these delays, issue the backtrace NMI only from
the first waiter. The destination CPU's other waiters can make use of
backtrace obtained from the first waiter's NMI.

Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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smp: Reduce logging due to dump_stack of CSD waiters

If a waiter is waiting for CSD lock, its call stack will not change
between first and subsequent hang detection for the same CSD lock.
Therefore,

smp: Reduce logging due to dump_stack of CSD waiters

If a waiter is waiting for CSD lock, its call stack will not change
between first and subsequent hang detection for the same CSD lock.
Therefore, do dump_stack only for first-time detection for a given waiter.

This avoids excessive logging on systems with hundreds of CPUs where
repetitive dump_stack from hundreds of CPUs would otherwise flood the
console.

Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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Merge branch 'master' into mm-hotfixes-stable

Merge branch 'for-6.5/apple' into for-linus

- improved support for Keychron K8 keyboard (Lasse Brun)

Merge tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP updates from Thomas Gleixner:
"A large update for SMP management:

- Parallel CPU bringup

Merge tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP updates from Thomas Gleixner:
"A large update for SMP management:

- Parallel CPU bringup

The reason why people are interested in parallel bringup is to
shorten the (kexec) reboot time of cloud servers to reduce the
downtime of the VM tenants.

The current fully serialized bringup does the following per AP:

1) Prepare callbacks (allocate, intialize, create threads)
2) Kick the AP alive (e.g. INIT/SIPI on x86)
3) Wait for the AP to report alive state
4) Let the AP continue through the atomic bringup
5) Let the AP run the threaded bringup to full online state

There are two significant delays:

#3 The time for an AP to report alive state in start_secondary()
on x86 has been measured in the range between 350us and 3.5ms
depending on vendor and CPU type, BIOS microcode size etc.

#4 The atomic bringup does the microcode update. This has been
measured to take up to ~8ms on the primary threads depending
on the microcode patch size to apply.

On a two socket SKL server with 56 cores (112 threads) the boot CPU
spends on current mainline about 800ms busy waiting for the APs to
come up and apply microcode. That's more than 80% of the actual
onlining procedure.

This can be reduced significantly by splitting the bringup
mechanism into two parts:

1) Run the prepare callbacks and kick the AP alive for each AP
which needs to be brought up.

The APs wake up, do their firmware initialization and run the
low level kernel startup code including microcode loading in
parallel up to the first synchronization point. (#1 and #2
above)

2) Run the rest of the bringup code strictly serialized per CPU
(#3 - #5 above) as it's done today.

Parallelizing that stage of the CPU bringup might be possible
in theory, but it's questionable whether required surgery
would be justified for a pretty small gain.

If the system is large enough the first AP is already waiting at
the first synchronization point when the boot CPU finished the
wake-up of the last AP. That reduces the AP bringup time on that
SKL from ~800ms to ~80ms, i.e. by a factor ~10x.

The actual gain varies wildly depending on the system, CPU,
microcode patch size and other factors. There are some
opportunities to reduce the overhead further, but that needs some
deep surgery in the x86 CPU bringup code.

For now this is only enabled on x86, but the core functionality
obviously works for all SMP capable architectures.

- Enhancements for SMP function call tracing so it is possible to
locate the scheduling and the actual execution points. That allows
to measure IPI delivery time precisely"

* tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
trace,smp: Add tracepoints for scheduling remotelly called functions
trace,smp: Add tracepoints around remotelly called functions
MAINTAINERS: Add CPU HOTPLUG entry
x86/smpboot: Fix the parallel bringup decision
x86/realmode: Make stack lock work in trampoline_compat()
x86/smp: Initialize cpu_primary_thread_mask late
cpu/hotplug: Fix off by one in cpuhp_bringup_mask()
x86/apic: Fix use of X{,2}APIC_ENABLE in asm with older binutils
x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it
x86/smpboot: Support parallel startup of secondary CPUs
x86/smpboot: Implement a bit spinlock to protect the realmode stack
x86/apic: Save the APIC virtual base address
cpu/hotplug: Allow "parallel" bringup up to CPUHP_BP_KICK_AP_STATE
x86/apic: Provide cpu_primary_thread mask
x86/smpboot: Enable split CPU startup
cpu/hotplug: Provide a split up CPUHP_BRINGUP mechanism
cpu/hotplug: Reset task stack state in _cpu_up()
cpu/hotplug: Remove unused state functions
riscv: Switch to hotplug core state synchronization
parisc: Switch to hotplug core state synchronization
...

show more ...

trace,smp: Add tracepoints for scheduling remotelly called functions

Add a tracepoint for when a CSD is queued to a remote CPU's
call_single_queue. This allows finding exactly which CPU queued a giv

trace,smp: Add tracepoints for scheduling remotelly called functions

Add a tracepoint for when a CSD is queued to a remote CPU's
call_single_queue. This allows finding exactly which CPU queued a given CSD
when looking at a csd_function_{entry,exit} event, and also enables us to
accurately measure IPI delivery time with e.g. a synthetic event:

$ echo 'hist:keys=cpu,csd.hex:ts=common_timestamp.usecs' >\
/sys/kernel/tracing/events/smp/csd_queue_cpu/trigger
$ echo 'csd_latency unsigned int dst_cpu; unsigned long csd; u64 time' >\
/sys/kernel/tracing/synthetic_events
$ echo \
'hist:keys=common_cpu,csd.hex:'\
'time=common_timestamp.usecs-$ts:'\
'onmatch(smp.csd_queue_cpu).trace(csd_latency,common_cpu,csd,$time)' >\
/sys/kernel/tracing/events/smp/csd_function_entry/trigger

$ trace-cmd record -e 'synthetic:csd_latency' hackbench
$ trace-cmd report
<...>-467 [001] 21.824263: csd_queue_cpu: cpu=0 callsite=try_to_wake_up+0x2ea func=sched_ttwu_pending csd=0xffff8880076148b8
<...>-467 [001] 21.824280: ipi_send_cpu: cpu=0 callsite=try_to_wake_up+0x2ea callback=generic_smp_call_function_single_interrupt+0x0
<...>-489 [000] 21.824299: csd_function_entry: func=sched_ttwu_pending csd=0xffff8880076148b8
<...>-489 [000] 21.824320: csd_latency: dst_cpu=0, csd=18446612682193848504, time=36

Suggested-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Tested-and-reviewed-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230615065944.188876-7-leobras@redhat.com

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trace,smp: Add tracepoints around remotelly called functions

The recently added ipi_send_{cpu,cpumask} tracepoints allow finding sources
of IPIs targeting CPUs running latency-sensitive applications

trace,smp: Add tracepoints around remotelly called functions

The recently added ipi_send_{cpu,cpumask} tracepoints allow finding sources
of IPIs targeting CPUs running latency-sensitive applications.

For NOHZ_FULL CPUs, all IPIs are interference, and those tracepoints are
sufficient to find them and work on getting rid of them. In some setups
however, not *all* IPIs are to be suppressed, but long-running IPI
callbacks can still be problematic.

Add a pair of tracepoints to mark the start and end of processing a CSD IPI
callback, similar to what exists for softirq, workqueue or timer callbacks.

Signed-off-by: Leonardo Bras <leobras@redhat.com>
Tested-and-reviewed-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230615065944.188876-5-leobras@redhat.com

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Merge drm/drm-next into drm-misc-next-fixes

Backmerging to sync drm-misc-next-fixes with drm-misc-next.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patche

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patches depend on these helpers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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Merge tag 'v6.4-rc4' into wpan-next/staging

Linux 6.4-rc4

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

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Merge drm/drm-next into drm-intel-next

Backmerge to get some hwmon dependencies.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>