Merge tag 'v6.6.35' into dev-6.6

This is the 6.6.35 stable release

tick/nohz_full: Don't abuse smp_call_function_single() in tick_setup_device()

commit 07c54cc5988f19c9642fd463c2dbdac7fc52f777 upstream.

After the recent commit 5097cbcb38e6 ("sched/isolation: Preve

tick/nohz_full: Don't abuse smp_call_function_single() in tick_setup_device()

commit 07c54cc5988f19c9642fd463c2dbdac7fc52f777 upstream.

After the recent commit 5097cbcb38e6 ("sched/isolation: Prevent boot crash
when the boot CPU is nohz_full") the kernel no longer crashes, but there is
another problem.

In this case tick_setup_device() calls tick_take_do_timer_from_boot() to
update tick_do_timer_cpu and this triggers the WARN_ON_ONCE(irqs_disabled)
in smp_call_function_single().

Kill tick_take_do_timer_from_boot() and just use WRITE_ONCE(), the new
comment explains why this is safe (thanks Thomas!).

Fixes: 08ae95f4fd3b ("nohz_full: Allow the boot CPU to be nohz_full")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240528122019.GA28794@redhat.com
Link: https://lore.kernel.org/all/20240522151742.GA10400@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.

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>

Merge branch 'master' into mm-hotfixes-stable

Merge tag 'v6.4' into rdma.git for-next

Linux 6.4

Resolve conflicts between rdma rc and next in rxe_cq matching linux-next:

drivers/infiniband/sw/rxe/rxe_cq.c:
https://lore.kernel.org/r/20230622

Merge tag 'v6.4' into rdma.git for-next

Linux 6.4

Resolve conflicts between rdma rc and next in rxe_cq matching linux-next:

drivers/infiniband/sw/rxe/rxe_cq.c:
https://lore.kernel.org/r/20230622115246.365d30ad@canb.auug.org.au

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

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

Cross-merge networking fixes after downstream PR.

Conflicts:

tools/testing/selftests/net/fcnal-test.sh
d7a2fc1437f7 ("selftests: ne

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

Cross-merge networking fixes after downstream PR.

Conflicts:

tools/testing/selftests/net/fcnal-test.sh
d7a2fc1437f7 ("selftests: net: fcnal-test: check if FIPS mode is enabled")
dd017c72dde6 ("selftests: fcnal: Test SO_DONTROUTE on TCP sockets.")
https://lore.kernel.org/all/5007b52c-dd16-dbf6-8d64-b9701bfa498b@tessares.net/
https://lore.kernel.org/all/20230619105427.4a0df9b3@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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Merge tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
"A single regression fix for a regression fix:

For a long time

Merge tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
"A single regression fix for a regression fix:

For a long time the tick was aligned to clock MONOTONIC so that the
tick event happened at a multiple of nanoseconds per tick starting
from clock MONOTONIC = 0.

At some point this changed as the refined jiffies clocksource which is
used during boot before the TSC or other clocksources becomes usable,
was adjusted with a boot offset, so that time 0 is closer to the point
where the kernel starts.

This broke the assumption in the tick code that when the tick setup
happens early on ktime_get() will return a multiple of nanoseconds per
tick. As a consequence applications which aligned their periodic
execution so that it does not collide with the tick were not longer
guaranteed that the tick period starts from time 0.

The fix for this regression was to realign the tick when it is
initially set up to a multiple of tick periods. That works as long as
the underlying tick device supports periodic mode, but breaks under
certain conditions when the tick device supports only one shot mode.

Depending on the offset, the alignment delta to clock MONOTONIC can
get in a range where the minimal programming delta of the underlying
clock event device is larger than the calculated delta to the next
tick. This results in a boot hang as the tick code tries to play catch
up, but as the tick never fires jiffies are not advanced so it keeps
trying for ever.

Solve this by moving the tick alignement into the NOHZ / HIGHRES
enablement code because at that point it is guaranteed that the
underlying clocksource is high resolution capable and not longer
depending on the tick.

This is far before user space starts, so at the point where
applications try to align their timers, the old behaviour of the tick
happening at a multiple of nanoseconds per tick starting from clock
MONOTONIC = 0 is restored"

* tag 'timers-urgent-2023-06-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/common: Align tick period during sched_timer setup

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tick/common: Align tick period during sched_timer setup

The tick period is aligned very early while the first clock_event_device is
registered. At that point the system runs in periodic mode and swi

tick/common: Align tick period during sched_timer setup

The tick period is aligned very early while the first clock_event_device is
registered. At that point the system runs in periodic mode and switches
later to one-shot mode if possible.

The next wake-up event is programmed based on the aligned value
(tick_next_period) but the delta value, that is used to program the
clock_event_device, is computed based on ktime_get().

With the subtracted offset, the device fires earlier than the exact time
frame. With a large enough offset the system programs the timer for the
next wake-up and the remaining time left is too small to make any boot
progress. The system hangs.

Move the alignment later to the setup of tick_sched timer. At this point
the system switches to oneshot mode and a high resolution clocksource is
available. At this point it is safe to align tick_next_period because
ktime_get() will now return accurate (not jiffies based) time.

[bigeasy: Patch description + testing].

Fixes: e9523a0d81899 ("tick/common: Align tick period with the HZ tick.")
Reported-by: Mathias Krause <minipli@grsecurity.net>
Reported-by: "Bhatnagar, Rishabh" <risbhat@amazon.com>
Suggested-by: Mathias Krause <minipli@grsecurity.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Tested-by: Mathias Krause <minipli@grsecurity.net>
Acked-by: SeongJae Park <sj@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/5a56290d-806e-b9a5-f37c-f21958b5a8c0@grsecurity.net
Link: https://lore.kernel.org/12c6f9a3-d087-b824-0d05-0d18c9bc1bf3@amazon.com
Link: https://lore.kernel.org/r/20230615091830.RxMV2xf_@linutronix.de

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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>

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

Let's bring 6.4-rc1 in drm-misc-fixes to start the new fix cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

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

Start the 6.5 release cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Merge tag 'timers-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timers and timekeeping updates from Thomas Gleixner:

- Improve the VDSO build time checks to cover

Merge tag 'timers-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timers and timekeeping updates from Thomas Gleixner:

- Improve the VDSO build time checks to cover all dynamic relocations

VDSO does not allow dynamic relocations, but the build time check is
incomplete and fragile.

It's based on architectures specifying the relocation types to search
for and does not handle R_*_NONE relocation entries correctly.
R_*_NONE relocations are injected by some GNU ld variants if they
fail to determine the exact .rel[a]/dyn_size to cover trailing zeros.
R_*_NONE relocations must be ignored by dynamic loaders, so they
should be ignored in the build time check too.

Remove the architecture specific relocation types to check for and
validate strictly that no other relocations than R_*_NONE end up in
the VSDO .so file.

- Prefer signal delivery to the current thread for
CLOCK_PROCESS_CPUTIME_ID based posix-timers

Such timers prefer to deliver the signal to the main thread of a
process even if the context in which the timer expires is the current
task. This has the downside that it might wake up an idle thread.

As there is no requirement or guarantee that the signal has to be
delivered to the main thread, avoid this by preferring the current
task if it is part of the thread group which shares sighand.

This not only avoids waking idle threads, it also distributes the
signal delivery in case of multiple timers firing in the context of
different threads close to each other better.

- Align the tick period properly (again)

For a long time the tick was starting at CLOCK_MONOTONIC zero, which
allowed users space applications to either align with the tick or to
place a periodic computation so that it does not interfere with the
tick. The alignement of the tick period was more by chance than by
intention as the tick is set up before a high resolution clocksource
is installed, i.e. timekeeping is still tick based and the tick
period advances from there.

The early enablement of sched_clock() broke this alignement as the
time accumulated by sched_clock() is taken into account when
timekeeping is initialized. So the base value now(CLOCK_MONOTONIC) is
not longer a multiple of tick periods, which breaks applications
which relied on that behaviour.

Cure this by aligning the tick starting point to the next multiple of
tick periods, i.e 1000ms/CONFIG_HZ.

- A set of NOHZ fixes and enhancements:

* Cure the concurrent writer race for idle and IO sleeptime
statistics

The statitic values which are exposed via /proc/stat are updated
from the CPU local idle exit and remotely by cpufreq, but that
happens without any form of serialization. As a consequence
sleeptimes can be accounted twice or worse.

Prevent this by restricting the accumulation writeback to the CPU
local idle exit and let the remote access compute the accumulated
value.

* Protect idle/iowait sleep time with a sequence count

Reading idle/iowait sleep time, e.g. from /proc/stat, can race
with idle exit updates. As a consequence the readout may result
in random and potentially going backwards values.

Protect this by a sequence count, which fixes the idle time
statistics issue, but cannot fix the iowait time problem because
iowait time accounting races with remote wake ups decrementing
the remote runqueues nr_iowait counter. The latter is impossible
to fix, so the only way to deal with that is to document it
properly and to remove the assertion in the selftest which
triggers occasionally due to that.

* Restructure struct tick_sched for better cache layout

* Some small cleanups and a better cache layout for struct
tick_sched

- Implement the missing timer_wait_running() callback for POSIX CPU
timers

For unknown reason the introduction of the timer_wait_running()
callback missed to fixup posix CPU timers, which went unnoticed for
almost four years.

While initially only targeted to prevent livelocks between a timer
deletion and the timer expiry function on PREEMPT_RT enabled kernels,
it turned out that fixing this for mainline is not as trivial as just
implementing a stub similar to the hrtimer/timer callbacks.

The reason is that for CONFIG_POSIX_CPU_TIMERS_TASK_WORK enabled
systems there is a livelock issue independent of RT.

CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y moves the expiry of POSIX CPU
timers out from hard interrupt context to task work, which is handled
before returning to user space or to a VM. The expiry mechanism moves
the expired timers to a stack local list head with sighand lock held.
Once sighand is dropped the task can be preempted and a task which
wants to delete a timer will spin-wait until the expiry task is
scheduled back in. In the worst case this will end up in a livelock
when the preempting task and the expiry task are pinned on the same
CPU.

The timer wheel has a timer_wait_running() mechanism for RT, which
uses a per CPU timer-base expiry lock which is held by the expiry
code and the task waiting for the timer function to complete blocks
on that lock.

This does not work in the same way for posix CPU timers as there is
no timer base and expiry for process wide timers can run on any task
belonging to that process, but the concept of waiting on an expiry
lock can be used too in a slightly different way.

Add a per task mutex to struct posix_cputimers_work, let the expiry
task hold it accross the expiry function and let the deleting task
which waits for the expiry to complete block on the mutex.

In the non-contended case this results in an extra
mutex_lock()/unlock() pair on both sides.

This avoids spin-waiting on a task which is scheduled out, prevents
the livelock and cures the problem for RT and !RT systems

* tag 'timers-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix-cpu-timers: Implement the missing timer_wait_running callback
selftests/proc: Assert clock_gettime(CLOCK_BOOTTIME) VS /proc/uptime monotonicity
selftests/proc: Remove idle time monotonicity assertions
MAINTAINERS: Remove stale email address
timers/nohz: Remove middle-function __tick_nohz_idle_stop_tick()
timers/nohz: Add a comment about broken iowait counter update race
timers/nohz: Protect idle/iowait sleep time under seqcount
timers/nohz: Only ever update sleeptime from idle exit
timers/nohz: Restructure and reshuffle struct tick_sched
tick/common: Align tick period with the HZ tick.
selftests/timers/posix_timers: Test delivery of signals across threads
posix-timers: Prefer delivery of signals to the current thread
vdso: Improve cmd_vdso_check to check all dynamic relocations

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tick/common: Align tick period with the HZ tick.

With HIGHRES enabled tick_sched_timer() is programmed every jiffy to
expire the timer_list timers. This timer is programmed accurate in
respect to CL

tick/common: Align tick period with the HZ tick.

With HIGHRES enabled tick_sched_timer() is programmed every jiffy to
expire the timer_list timers. This timer is programmed accurate in
respect to CLOCK_MONOTONIC so that 0 seconds and nanoseconds is the
first tick and the next one is 1000/CONFIG_HZ ms later. For HZ=250 it is
every 4 ms and so based on the current time the next tick can be
computed.

This accuracy broke since the commit mentioned below because the jiffy
based clocksource is initialized with higher accuracy in
read_persistent_wall_and_boot_offset(). This higher accuracy is
inherited during the setup in tick_setup_device(). The timer still fires
every 4ms with HZ=250 but timer is no longer aligned with
CLOCK_MONOTONIC with 0 as it origin but has an offset in the us/ns part
of the timestamp. The offset differs with every boot and makes it
impossible for user land to align with the tick.

Align the tick period with CLOCK_MONOTONIC ensuring that it is always a
multiple of 1000/CONFIG_HZ ms.

Fixes: 857baa87b6422 ("sched/clock: Enable sched clock early")
Reported-by: Gusenleitner Klaus <gus@keba.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20230406095735.0_14edn3@linutronix.de
Link: https://lore.kernel.org/r/20230418122639.ikgfvu3f@linutronix.de

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Merge branch 'next' into for-linus

Prepare input updates for 5.17 merge window.

Merge tag 'v5.15' into next

Sync up with the mainline to get the latest APIs and DT bindings.