Merge tag 'kvmarm-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #1

- Fix pKVM error path on init, making sure we do not chang

Merge tag 'kvmarm-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #1

- Fix pKVM error path on init, making sure we do not change critical
system registers as we're about to fail

- Make sure that the host's vector length is at capped by a value
common to all CPUs

- Fix kvm_has_feat*() handling of "negative" features, as the current
code is pretty broken

- Promote Joey to the status of official reviewer, while James steps
down -- hopefully only temporarly

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Merge tag 'asoc-fix-v6.12-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v6.12

A bunch of fixes here that came in during the merge window and t

Merge tag 'asoc-fix-v6.12-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v6.12

A bunch of fixes here that came in during the merge window and the first
week of release, plus some new quirks and device IDs. There's nothing
major here, it's a bit bigger than it might've been due to there being
no fixes sent during the merge window due to your vacation.

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Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

Required for a panthor fix that broke when
FOP_UNSIGNED_OFFSET was added in place of FMODE_UNSIGNED_OFFSET.

Signed-off-by: Maarten L

Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

Required for a panthor fix that broke when
FOP_UNSIGNED_OFFSET was added in place of FMODE_UNSIGNED_OFFSET.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

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Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Cross-merge networking fixes after downstream PR.

No conflicts and no adjacent changes.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Merge tag 'sched_ext-for-6.12-rc1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext fixes from Tejun Heo:

- When sched_ext is in bypass mode (e.g. while disabli

Merge tag 'sched_ext-for-6.12-rc1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext fixes from Tejun Heo:

- When sched_ext is in bypass mode (e.g. while disabling the BPF
scheduler), it was using one DSQ to implement global FIFO scheduling
as all it has to do is guaranteeing reasonable forward progress.

On multi-socket machines, this can lead to live-lock conditions under
certain workloads. Fixed by splitting the queue used for FIFO
scheduling per NUMA node. This required several preparation patches.

- Hotplug tests on powerpc could reliably trigger deadlock while
enabling a BPF scheduler.

This was caused by cpu_hotplug_lock nesting inside scx_fork_rwsem and
then CPU hotplug path trying to fork a new thread while holding
cpu_hotplug_lock.

Fixed by restructuring locking in enable and disable paths so that
the two locks are not coupled. This required several preparation
patches which also fixed a couple other issues in the enable path.

- A build fix for !CONFIG_SMP

- Userspace tooling sync and updates

* tag 'sched_ext-for-6.12-rc1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext:
sched_ext: Remove redundant p->nr_cpus_allowed checker
sched_ext: Decouple locks in scx_ops_enable()
sched_ext: Decouple locks in scx_ops_disable_workfn()
sched_ext: Add scx_cgroup_enabled to gate cgroup operations and fix scx_tg_online()
sched_ext: Enable scx_ops_init_task() separately
sched_ext: Fix SCX_TASK_INIT -> SCX_TASK_READY transitions in scx_ops_enable()
sched_ext: Initialize in bypass mode
sched_ext: Remove SCX_OPS_PREPPING
sched_ext: Relocate check_hotplug_seq() call in scx_ops_enable()
sched_ext: Use shorter slice while bypassing
sched_ext: Split the global DSQ per NUMA node
sched_ext: Relocate find_user_dsq()
sched_ext: Allow only user DSQs for scx_bpf_consume(), scx_bpf_dsq_nr_queued() and bpf_iter_scx_dsq_new()
scx_flatcg: Use a user DSQ for fallback instead of SCX_DSQ_GLOBAL
tools/sched_ext: Receive misc updates from SCX repo
sched_ext: Add __COMPAT helpers for features added during v6.12 devel cycle
sched_ext: Build fix for !CONFIG_SMP

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scx_flatcg: Use a user DSQ for fallback instead of SCX_DSQ_GLOBAL

scx_flatcg was using SCX_DSQ_GLOBAL for fallback handling. However, it is
assuming that SCX_DSQ_GLOBAL isn't automatically consumed,

scx_flatcg: Use a user DSQ for fallback instead of SCX_DSQ_GLOBAL

scx_flatcg was using SCX_DSQ_GLOBAL for fallback handling. However, it is
assuming that SCX_DSQ_GLOBAL isn't automatically consumed, which was true a
while ago but is no longer the case. Also, there are further changes planned
for SCX_DSQ_GLOBAL which will disallow explicit consumption from it. Switch
to a user DSQ for fallback.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>

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tools/sched_ext: Receive misc updates from SCX repo

Receive misc tools/sched_ext updates from https://github.com/sched-ext/scx
to sync userspace bits.

- LSP macros to help language servers.

- bpf_

tools/sched_ext: Receive misc updates from SCX repo

Receive misc tools/sched_ext updates from https://github.com/sched-ext/scx
to sync userspace bits.

- LSP macros to help language servers.

- bpf_cpumask_weight() declaration and cast_mask() helper.

- Cosmetic updates to scx_flatcg.bpf.c.

Signed-off-by: Tejun Heo <tj@kernel.org>

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sched_ext: Add __COMPAT helpers for features added during v6.12 devel cycle

cgroup support and scx_bpf_dispatch[_vtime]_from_dsq() are newly added since
8bb30798fd6e ("sched_ext: Fixes incorrect typ

sched_ext: Add __COMPAT helpers for features added during v6.12 devel cycle

cgroup support and scx_bpf_dispatch[_vtime]_from_dsq() are newly added since
8bb30798fd6e ("sched_ext: Fixes incorrect type in bpf_scx_init()") which is
the current earliest commit targeted by BPF schedulers. Add compat helpers
for them and apply them in the example schedulers.

These will be dropped after a few kernel releases. The exact backward
compatibility window hasn't been decided yet.

Signed-off-by: Tejun Heo <tj@kernel.org>

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Merge tag 'sched_ext-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext support from Tejun Heo:
"This implements a new scheduler class called ‘ext_sched_class’,

Merge tag 'sched_ext-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext support from Tejun Heo:
"This implements a new scheduler class called ‘ext_sched_class’, or
sched_ext, which allows scheduling policies to be implemented as BPF
programs.

The goals of this are:

- Ease of experimentation and exploration: Enabling rapid iteration
of new scheduling policies.

- Customization: Building application-specific schedulers which
implement policies that are not applicable to general-purpose
schedulers.

- Rapid scheduler deployments: Non-disruptive swap outs of scheduling
policies in production environments"

See individual commits for more documentation, but also the cover letter
for the latest series:

Link: https://lore.kernel.org/all/20240618212056.2833381-1-tj@kernel.org/

* tag 'sched_ext-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (110 commits)
sched: Move update_other_load_avgs() to kernel/sched/pelt.c
sched_ext: Don't trigger ops.quiescent/runnable() on migrations
sched_ext: Synchronize bypass state changes with rq lock
scx_qmap: Implement highpri boosting
sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()
sched_ext: Compact struct bpf_iter_scx_dsq_kern
sched_ext: Replace consume_local_task() with move_local_task_to_local_dsq()
sched_ext: Move consume_local_task() upward
sched_ext: Move sanity check and dsq_mod_nr() into task_unlink_from_dsq()
sched_ext: Reorder args for consume_local/remote_task()
sched_ext: Restructure dispatch_to_local_dsq()
sched_ext: Fix processs_ddsp_deferred_locals() by unifying DTL_INVALID handling
sched_ext: Make find_dsq_for_dispatch() handle SCX_DSQ_LOCAL_ON
sched_ext: Refactor consume_remote_task()
sched_ext: Rename scx_kfunc_set_sleepable to unlocked and relocate
sched_ext: Add missing static to scx_dump_data
sched_ext: Add missing static to scx_has_op[]
sched_ext: Temporarily work around pick_task_scx() being called without balance_scx()
sched_ext: Add a cgroup scheduler which uses flattened hierarchy
sched_ext: Add cgroup support
...

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sched_ext: Add a cgroup scheduler which uses flattened hierarchy

This patch adds scx_flatcg example scheduler which implements hierarchical
weight-based cgroup CPU control by flattening the cgroup h

sched_ext: Add a cgroup scheduler which uses flattened hierarchy

This patch adds scx_flatcg example scheduler which implements hierarchical
weight-based cgroup CPU control by flattening the cgroup hierarchy into a
single layer by compounding the active weight share at each level.

This flattening of hierarchy can bring a substantial performance gain when
the cgroup hierarchy is nested multiple levels. in a simple benchmark using
wrk[8] on apache serving a CGI script calculating sha1sum of a small file,
it outperforms CFS by ~3% with CPU controller disabled and by ~10% with two
apache instances competing with 2:1 weight ratio nested four level deep.

However, the gain comes at the cost of not being able to properly handle
thundering herd of cgroups. For example, if many cgroups which are nested
behind a low priority parent cgroup wake up around the same time, they may
be able to consume more CPU cycles than they are entitled to. In many use
cases, this isn't a real concern especially given the performance gain.
Also, there are ways to mitigate the problem further by e.g. introducing an
extra scheduling layer on cgroup delegation boundaries.

v5: - Updated to specify SCX_OPS_HAS_CGROUP_WEIGHT instead of
SCX_OPS_KNOB_CGROUP_WEIGHT.

v4: - Revert reference counted kptr for cgv_node as the change caused easily
reproducible stalls.

v3: - Updated to reflect the core API changes including ops.init/exit_task()
and direct dispatch from ops.select_cpu(). Fixes and improvements
including additional statistics.

- Use reference counted kptr for cgv_node instead of xchg'ing against
stash location.

- Dropped '-p' option.

v2: - Use SCX_BUG[_ON]() to simplify error handling.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Vernet <dvernet@meta.com>
Acked-by: Josh Don <joshdon@google.com>
Acked-by: Hao Luo <haoluo@google.com>
Acked-by: Barret Rhoden <brho@google.com>

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