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<title>user/sven/linux.git/kernel, branch v6.14</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.14</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.14'/>
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<updated>2025-03-21T15:48:40Z</updated>
<entry>
<title>Merge tag 'sched-urgent-2025-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-03-21T15:48:40Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-21T15:48:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=cb90c8df91d08aebb62ef77bd1c7f41a31bdc924'/>
<id>urn:sha1:cb90c8df91d08aebb62ef77bd1c7f41a31bdc924</id>
<content type='text'>
Pull scheduler fix from Ingo Molnar:
 "Revert a scheduler performance optimization that regressed other
  workloads"

* tag 'sched-urgent-2025-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "sched/core: Reduce cost of sched_move_task when config autogroup"
</content>
</entry>
<entry>
<title>Merge tag 'dma-mapping-6.14-2025-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux</title>
<updated>2025-03-20T23:55:24Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-20T23:55:24Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a1cffe8cc8aef85f1b07c4464f0998b9785b795a'/>
<id>urn:sha1:a1cffe8cc8aef85f1b07c4464f0998b9785b795a</id>
<content type='text'>
Pull dma-mapping fix from Marek Szyprowski:

 - fix missing clear bdr in check_ram_in_range_map() (Baochen Qiang)

* tag 'dma-mapping-6.14-2025-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
  dma-mapping: fix missing clear bdr in check_ram_in_range_map()
</content>
</entry>
<entry>
<title>Merge tag 'probes-fixes-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2025-03-17T21:30:31Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-17T21:30:31Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=47c7efa4f0c335d039d9f5795022ba9b589cbe4a'/>
<id>urn:sha1:47c7efa4f0c335d039d9f5795022ba9b589cbe4a</id>
<content type='text'>
Pull probes fixes from Masami Hiramatsu:

 - Clean up tprobe correctly when module unload

   Tracepoint probes do not set TRACEPOINT_STUB on the 'tpoint' pointer
   when unloading a module, thus they show as a normal 'fprobe' instead
   of 'tprobe' and never come back

 - Fix leakage of tprobe module refcount

   When a tprobe's target module is loaded, it gets the module's
   refcount in the module notifier but forgot to put it after
   registering the probe on it.

   Fix it by getting the refcount only when registering tprobe.

* tag 'probes-fixes-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: tprobe-events: Fix leakage of module refcount
  tracing: tprobe-events: Fix to clean up tprobe correctly when module unload
</content>
</entry>
<entry>
<title>Merge tag 'trace-v6.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace</title>
<updated>2025-03-16T19:05:00Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-16T19:05:00Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ad87a8d0c435a97e2bdcf714d7e1a84ab5fda1ad'/>
<id>urn:sha1:ad87a8d0c435a97e2bdcf714d7e1a84ab5fda1ad</id>
<content type='text'>
Pull tracing fix from Steven Rostedt:
 "Fix ref count of trace_array in error path of histogram file open

  Tracing instances have a ref count to keep them around while files
  within their directories are open. This prevents them from being
  deleted while they are used.

  The histogram code had some files that needed to take the ref count
  and that was added, but the error paths did not decrement the ref
  counts. This caused the instances from ever being removed if a
  histogram file failed to open due to some error"

* tag 'trace-v6.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Correct the refcount if the hist/hist_debug file fails to open
</content>
</entry>
<entry>
<title>Revert "sched/core: Reduce cost of sched_move_task when config autogroup"</title>
<updated>2025-03-15T09:34:27Z</updated>
<author>
<name>Dietmar Eggemann</name>
<email>dietmar.eggemann@arm.com</email>
</author>
<published>2025-03-14T15:13:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=76f970ce51c80f625eb6ddbb24e9cb51b977b598'/>
<id>urn:sha1:76f970ce51c80f625eb6ddbb24e9cb51b977b598</id>
<content type='text'>
This reverts commit eff6c8ce8d4d7faef75f66614dd20bb50595d261.

Hazem reported a 30% drop in UnixBench spawn test with commit
eff6c8ce8d4d ("sched/core: Reduce cost of sched_move_task when config
autogroup") on a m6g.xlarge AWS EC2 instance with 4 vCPUs and 16 GiB RAM
(aarch64) (single level MC sched domain):

  https://lkml.kernel.org/r/20250205151026.13061-1-hagarhem@amazon.com

There is an early bail from sched_move_task() if p-&gt;sched_task_group is
equal to p's 'cpu cgroup' (sched_get_task_group()). E.g. both are
pointing to taskgroup '/user.slice/user-1000.slice/session-1.scope'
(Ubuntu '22.04.5 LTS').

So in:

  do_exit()

    sched_autogroup_exit_task()

      sched_move_task()

        if sched_get_task_group(p) == p-&gt;sched_task_group
          return

        /* p is enqueued */
        dequeue_task()              \
        sched_change_group()        |
          task_change_group_fair()  |
            detach_task_cfs_rq()    |                              (1)
            set_task_rq()           |
            attach_task_cfs_rq()    |
        enqueue_task()              /

(1) isn't called for p anymore.

Turns out that the regression is related to sgs-&gt;group_util in
group_is_overloaded() and group_has_capacity(). If (1) isn't called for
all the 'spawn' tasks then sgs-&gt;group_util is ~900 and
sgs-&gt;group_capacity = 1024 (single CPU sched domain) and this leads to
group_is_overloaded() returning true (2) and group_has_capacity() false
(3) much more often compared to the case when (1) is called.

I.e. there are much more cases of 'group_is_overloaded' and
'group_fully_busy' in WF_FORK wakeup sched_balance_find_dst_cpu() which
then returns much more often a CPU != smp_processor_id() (5).

This isn't good for these extremely short running tasks (FORK + EXIT)
and also involves calling sched_balance_find_dst_group_cpu() unnecessary
(single CPU sched domain).

Instead if (1) is called for 'p-&gt;flags &amp; PF_EXITING' then the path
(4),(6) is taken much more often.

  select_task_rq_fair(..., wake_flags = WF_FORK)

    cpu = smp_processor_id()

    new_cpu = sched_balance_find_dst_cpu(..., cpu, ...)

      group = sched_balance_find_dst_group(..., cpu)

        do {

          update_sg_wakeup_stats()

            sgs-&gt;group_type = group_classify()

              if group_is_overloaded()                             (2)
                return group_overloaded

              if !group_has_capacity()                             (3)
                return group_fully_busy

              return group_has_spare                               (4)

        } while group

        if local_sgs.group_type &gt; idlest_sgs.group_type
          return idlest                                            (5)

        case group_has_spare:

          if local_sgs.idle_cpus &gt;= idlest_sgs.idle_cpus
            return NULL                                            (6)

Unixbench Tests './Run -c 4 spawn' on:

(a) VM AWS instance (m7gd.16xlarge) with v6.13 ('maxcpus=4 nr_cpus=4')
    and Ubuntu 22.04.5 LTS (aarch64).

    Shell &amp; test run in '/user.slice/user-1000.slice/session-1.scope'.

    w/o patch	w/ patch
    21005	27120

(b) i7-13700K with tip/sched/core ('nosmt maxcpus=8 nr_cpus=8') and
    Ubuntu 22.04.5 LTS (x86_64).

    Shell &amp; test run in '/A'.

    w/o patch	w/ patch
    67675	88806

CONFIG_SCHED_AUTOGROUP=y &amp; /sys/proc/kernel/sched_autogroup_enabled equal
0 or 1.

Reported-by: Hazem Mohamed Abuelfotoh &lt;abuehaze@amazon.com&gt;
Signed-off-by: Dietmar Eggemann &lt;dietmar.eggemann@arm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Reviewed-by: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Tested-by: Hagar Hemdan &lt;hagarhem@amazon.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: https://lore.kernel.org/r/20250314151345.275739-1-dietmar.eggemann@arm.com
</content>
</entry>
<entry>
<title>tracing: tprobe-events: Fix leakage of module refcount</title>
<updated>2025-03-14T23:37:47Z</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2025-03-13T01:00:10Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ac91052f0ae5be9e46211ba92cc31c0e3b0a933a'/>
<id>urn:sha1:ac91052f0ae5be9e46211ba92cc31c0e3b0a933a</id>
<content type='text'>
When enabling the tracepoint at loading module, the target module
refcount is incremented by find_tracepoint_in_module(). But it is
unnecessary because the module is not unloaded while processing
module loading callbacks.
Moreover, the refcount is not decremented in that function.
To be clear the module refcount handling, move the try_module_get()
callsite to trace_fprobe_create_internal(), where it is actually
required.

Link: https://lore.kernel.org/all/174182761071.83274.18334217580449925882.stgit@devnote2/

Fixes: 57a7e6de9e30 ("tracing/fprobe: Support raw tracepoints on future loaded modules")
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Cc: stable@vger.kernel.org</content>
</entry>
<entry>
<title>tracing: tprobe-events: Fix to clean up tprobe correctly when module unload</title>
<updated>2025-03-14T23:37:12Z</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2025-03-10T06:14:09Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0a8bb688aa824863716fc570d818b8659a79309d'/>
<id>urn:sha1:0a8bb688aa824863716fc570d818b8659a79309d</id>
<content type='text'>
When unloading module, the tprobe events are not correctly cleaned
up. Thus it becomes `fprobe-event` and never be enabled again even
if loading the same module again.

For example;

 # cd /sys/kernel/tracing
 # modprobe trace_events_sample
 # echo 't:my_tprobe foo_bar' &gt;&gt; dynamic_events
 # cat dynamic_events
t:tracepoints/my_tprobe foo_bar
 # rmmod trace_events_sample
 # cat dynamic_events
f:tracepoints/my_tprobe foo_bar

As you can see, the second time my_tprobe starts with 'f' instead
of 't'.

This unregisters the fprobe and tracepoint callback when module is
unloaded but marks the fprobe-event is tprobe-event.

Link: https://lore.kernel.org/all/174158724946.189309.15826571379395619524.stgit@mhiramat.tok.corp.google.com/

Fixes: 57a7e6de9e30 ("tracing/fprobe: Support raw tracepoints on future loaded modules")
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;</content>
</entry>
<entry>
<title>Merge tag 'sched-urgent-2025-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-03-14T19:56:46Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-14T19:56:46Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a22ea738f4539afc13aa34a34a631e5aae96bcf8'/>
<id>urn:sha1:a22ea738f4539afc13aa34a34a631e5aae96bcf8</id>
<content type='text'>
Pull scheduler fix from Ingo Molnar:
 "Fix a sleeping-while-atomic bug caused by a recent optimization
  utilizing static keys that didn't consider that the
  static_key_disable() call could be triggered in atomic context.

  Revert the optimization"

* tag 'sched-urgent-2025-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/clock: Don't define sched_clock_irqtime as static key
</content>
</entry>
<entry>
<title>Merge tag 'locking-urgent-2025-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-03-14T19:41:36Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-14T19:41:36Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=28c50999c977fc60ecbadfee4359a93116163d4f'/>
<id>urn:sha1:28c50999c977fc60ecbadfee4359a93116163d4f</id>
<content type='text'>
Pull misc locking fixes from Ingo Molnar:

 - Restrict the Rust runtime from unintended access to dynamically
   allocated LockClassKeys

 - KernelDoc annotation fix

 - Fix a lock ordering bug in semaphore::up(), related to trying to
   printk() and wake up the console within critical sections

* tag 'locking-urgent-2025-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/semaphore: Use wake_q to wake up processes outside lock critical section
  locking/rtmutex: Use the 'struct' keyword in kernel-doc comment
  rust: lockdep: Remove support for dynamically allocated LockClassKeys
</content>
</entry>
<entry>
<title>tracing: Correct the refcount if the hist/hist_debug file fails to open</title>
<updated>2025-03-14T12:29:12Z</updated>
<author>
<name>Tengda Wu</name>
<email>wutengda@huaweicloud.com</email>
</author>
<published>2025-03-14T06:53:35Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0b4ffbe4888a2c71185eaf5c1a02dd3586a9bc04'/>
<id>urn:sha1:0b4ffbe4888a2c71185eaf5c1a02dd3586a9bc04</id>
<content type='text'>
The function event_{hist,hist_debug}_open() maintains the refcount of
'file-&gt;tr' and 'file' through tracing_open_file_tr(). However, it does
not roll back these counts on subsequent failure paths, resulting in a
refcount leak.

A very obvious case is that if the hist/hist_debug file belongs to a
specific instance, the refcount leak will prevent the deletion of that
instance, as it relies on the condition 'tr-&gt;ref == 1' within
__remove_instance().

Fix this by calling tracing_release_file_tr() on all failure paths in
event_{hist,hist_debug}_open() to correct the refcount.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Zheng Yejian &lt;zhengyejian1@huawei.com&gt;
Link: https://lore.kernel.org/20250314065335.1202817-1-wutengda@huaweicloud.com
Fixes: 1cc111b9cddc ("tracing: Fix uaf issue when open the hist or hist_debug file")
Signed-off-by: Tengda Wu &lt;wutengda@huaweicloud.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
</feed>
