<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/kernel/time, branch v6.12.2</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>timers: Add missing READ_ONCE() in __run_timer_base()</title>
<updated>2024-12-05T13:01:22+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2024-10-30T07:53:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1dfa6c520022b72de65e64d845cecde8903d9f63'/>
<id>1dfa6c520022b72de65e64d845cecde8903d9f63</id>
<content type='text'>
[ Upstream commit 1d4199cbbe95efaba51304cfd844bd0ccd224e61 ]

__run_timer_base() checks base::next_expiry without holding
base::lock. That can race with a remote CPU updating next_expiry under the
lock. This is an intentional and harmless data race, but lacks a
READ_ONCE(), so KCSAN complains about this.

Add the missing READ_ONCE(). All other places are covered already.

Fixes: 79f8b28e85f8 ("timers: Annotate possible non critical data race of next_expiry")
Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Link: https://lore.kernel.org/all/87a5emyqk0.ffs@tglx
Closes: https://lore.kernel.org/oe-lkp/202410301205.ef8e9743-lkp@intel.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1d4199cbbe95efaba51304cfd844bd0ccd224e61 ]

__run_timer_base() checks base::next_expiry without holding
base::lock. That can race with a remote CPU updating next_expiry under the
lock. This is an intentional and harmless data race, but lacks a
READ_ONCE(), so KCSAN complains about this.

Add the missing READ_ONCE(). All other places are covered already.

Fixes: 79f8b28e85f8 ("timers: Annotate possible non critical data race of next_expiry")
Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Link: https://lore.kernel.org/all/87a5emyqk0.ffs@tglx
Closes: https://lore.kernel.org/oe-lkp/202410301205.ef8e9743-lkp@intel.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>time: Fix references to _msecs_to_jiffies() handling of values</title>
<updated>2024-12-05T13:01:22+00:00</updated>
<author>
<name>Miguel Ojeda</name>
<email>ojeda@kernel.org</email>
</author>
<published>2024-10-25T11:01:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b62a8825d3289c03d1e356f5f38e25081539d58c'/>
<id>b62a8825d3289c03d1e356f5f38e25081539d58c</id>
<content type='text'>
[ Upstream commit 92b043fd995a63a57aae29ff85a39b6f30cd440c ]

The details about the handling of the "normal" values were moved
to the _msecs_to_jiffies() helpers in commit ca42aaf0c861 ("time:
Refactor msecs_to_jiffies"). However, the same commit still mentioned
__msecs_to_jiffies() in the added documentation.

Thus point to _msecs_to_jiffies() instead.

Fixes: ca42aaf0c861 ("time: Refactor msecs_to_jiffies")
Signed-off-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/all/20241025110141.157205-2-ojeda@kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 92b043fd995a63a57aae29ff85a39b6f30cd440c ]

The details about the handling of the "normal" values were moved
to the _msecs_to_jiffies() helpers in commit ca42aaf0c861 ("time:
Refactor msecs_to_jiffies"). However, the same commit still mentioned
__msecs_to_jiffies() in the added documentation.

Thus point to _msecs_to_jiffies() instead.

Fixes: ca42aaf0c861 ("time: Refactor msecs_to_jiffies")
Signed-off-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/all/20241025110141.157205-2-ojeda@kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>time: Partially revert cleanup on msecs_to_jiffies() documentation</title>
<updated>2024-12-05T13:01:22+00:00</updated>
<author>
<name>Miguel Ojeda</name>
<email>ojeda@kernel.org</email>
</author>
<published>2024-10-25T11:01:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5c3a9f6f7f23cd2252f19dae43ab8f005ac85a14'/>
<id>5c3a9f6f7f23cd2252f19dae43ab8f005ac85a14</id>
<content type='text'>
[ Upstream commit b05aefc1f5886c8aece650c9c1639c87b976191a ]

The documentation's intention is to compare msecs_to_jiffies() (first
sentence) with __msecs_to_jiffies() (second sentence), which is what the
original documentation did. One of the cleanups in commit f3cb80804b82
("time: Fix various kernel-doc problems") may have thought the paragraph
was talking about the latter since that is what it is being documented.

Thus revert that part of the change.

Fixes: f3cb80804b82 ("time: Fix various kernel-doc problems")
Signed-off-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/all/20241025110141.157205-1-ojeda@kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b05aefc1f5886c8aece650c9c1639c87b976191a ]

The documentation's intention is to compare msecs_to_jiffies() (first
sentence) with __msecs_to_jiffies() (second sentence), which is what the
original documentation did. One of the cleanups in commit f3cb80804b82
("time: Fix various kernel-doc problems") may have thought the paragraph
was talking about the latter since that is what it is being documented.

Thus revert that part of the change.

Fixes: f3cb80804b82 ("time: Fix various kernel-doc problems")
Signed-off-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/all/20241025110141.157205-1-ojeda@kernel.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'net-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2024-10-24T23:43:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-10-24T23:43:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d44cd8226449114780a8554fd253c7e3d171a0a6'/>
<id>d44cd8226449114780a8554fd253c7e3d171a0a6</id>
<content type='text'>
Pull networking fixes from Paolo Abeni:
 "Including fixes from netfiler, xfrm and bluetooth.

  Oddly this includes a fix for a posix clock regression; in our
  previous PR we included a change there as a pre-requisite for
  networking one. That fix proved to be buggy and requires the follow-up
  included here. Thomas suggested we should send it, given we sent the
  buggy patch.

  Current release - regressions:

   - posix-clock: Fix unbalanced locking in pc_clock_settime()

   - netfilter: fix typo causing some targets not to load on IPv6

  Current release - new code bugs:

   - xfrm: policy: remove last remnants of pernet inexact list

  Previous releases - regressions:

   - core: fix races in netdev_tx_sent_queue()/dev_watchdog()

   - bluetooth: fix UAF on sco_sock_timeout

   - eth: hv_netvsc: fix VF namespace also in synthetic NIC
     NETDEV_REGISTER event

   - eth: usbnet: fix name regression

   - eth: be2net: fix potential memory leak in be_xmit()

   - eth: plip: fix transmit path breakage

  Previous releases - always broken:

   - sched: deny mismatched skip_sw/skip_hw flags for actions created by
     classifiers

   - netfilter: bpf: must hold reference on net namespace

   - eth: virtio_net: fix integer overflow in stats

   - eth: bnxt_en: replace ptp_lock with irqsave variant

   - eth: octeon_ep: add SKB allocation failures handling in
     __octep_oq_process_rx()

  Misc:

   - MAINTAINERS: add Simon as an official reviewer"

* tag 'net-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (40 commits)
  net: dsa: mv88e6xxx: support 4000ps cycle counter period
  net: dsa: mv88e6xxx: read cycle counter period from hardware
  net: dsa: mv88e6xxx: group cycle counter coefficients
  net: usb: qmi_wwan: add Fibocom FG132 0x0112 composition
  hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event
  net: dsa: microchip: disable EEE for KSZ879x/KSZ877x/KSZ876x
  Bluetooth: ISO: Fix UAF on iso_sock_timeout
  Bluetooth: SCO: Fix UAF on sco_sock_timeout
  Bluetooth: hci_core: Disable works on hci_unregister_dev
  posix-clock: posix-clock: Fix unbalanced locking in pc_clock_settime()
  r8169: avoid unsolicited interrupts
  net: sched: use RCU read-side critical section in taprio_dump()
  net: sched: fix use-after-free in taprio_change()
  net/sched: act_api: deny mismatched skip_sw/skip_hw flags for actions created by classifiers
  net: usb: usbnet: fix name regression
  mlxsw: spectrum_router: fix xa_store() error checking
  virtio_net: fix integer overflow in stats
  net: fix races in netdev_tx_sent_queue()/dev_watchdog()
  net: wwan: fix global oob in wwan_rtnl_policy
  netfilter: xtables: fix typo causing some targets not to load on IPv6
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from Paolo Abeni:
 "Including fixes from netfiler, xfrm and bluetooth.

  Oddly this includes a fix for a posix clock regression; in our
  previous PR we included a change there as a pre-requisite for
  networking one. That fix proved to be buggy and requires the follow-up
  included here. Thomas suggested we should send it, given we sent the
  buggy patch.

  Current release - regressions:

   - posix-clock: Fix unbalanced locking in pc_clock_settime()

   - netfilter: fix typo causing some targets not to load on IPv6

  Current release - new code bugs:

   - xfrm: policy: remove last remnants of pernet inexact list

  Previous releases - regressions:

   - core: fix races in netdev_tx_sent_queue()/dev_watchdog()

   - bluetooth: fix UAF on sco_sock_timeout

   - eth: hv_netvsc: fix VF namespace also in synthetic NIC
     NETDEV_REGISTER event

   - eth: usbnet: fix name regression

   - eth: be2net: fix potential memory leak in be_xmit()

   - eth: plip: fix transmit path breakage

  Previous releases - always broken:

   - sched: deny mismatched skip_sw/skip_hw flags for actions created by
     classifiers

   - netfilter: bpf: must hold reference on net namespace

   - eth: virtio_net: fix integer overflow in stats

   - eth: bnxt_en: replace ptp_lock with irqsave variant

   - eth: octeon_ep: add SKB allocation failures handling in
     __octep_oq_process_rx()

  Misc:

   - MAINTAINERS: add Simon as an official reviewer"

* tag 'net-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (40 commits)
  net: dsa: mv88e6xxx: support 4000ps cycle counter period
  net: dsa: mv88e6xxx: read cycle counter period from hardware
  net: dsa: mv88e6xxx: group cycle counter coefficients
  net: usb: qmi_wwan: add Fibocom FG132 0x0112 composition
  hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event
  net: dsa: microchip: disable EEE for KSZ879x/KSZ877x/KSZ876x
  Bluetooth: ISO: Fix UAF on iso_sock_timeout
  Bluetooth: SCO: Fix UAF on sco_sock_timeout
  Bluetooth: hci_core: Disable works on hci_unregister_dev
  posix-clock: posix-clock: Fix unbalanced locking in pc_clock_settime()
  r8169: avoid unsolicited interrupts
  net: sched: use RCU read-side critical section in taprio_dump()
  net: sched: fix use-after-free in taprio_change()
  net/sched: act_api: deny mismatched skip_sw/skip_hw flags for actions created by classifiers
  net: usb: usbnet: fix name regression
  mlxsw: spectrum_router: fix xa_store() error checking
  virtio_net: fix integer overflow in stats
  net: fix races in netdev_tx_sent_queue()/dev_watchdog()
  net: wwan: fix global oob in wwan_rtnl_policy
  netfilter: xtables: fix typo causing some targets not to load on IPv6
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>posix-clock: posix-clock: Fix unbalanced locking in pc_clock_settime()</title>
<updated>2024-10-23T14:05:01+00:00</updated>
<author>
<name>Jinjie Ruan</name>
<email>ruanjinjie@huawei.com</email>
</author>
<published>2024-10-18T10:07:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6e62807c7fbb3c758d233018caf94dfea9c65dbd'/>
<id>6e62807c7fbb3c758d233018caf94dfea9c65dbd</id>
<content type='text'>
If get_clock_desc() succeeds, it calls fget() for the clockid's fd,
and get the clk-&gt;rwsem read lock, so the error path should release
the lock to make the lock balance and fput the clockid's fd to make
the refcount balance and release the fd related resource.

However the below commit left the error path locked behind resulting in
unbalanced locking. Check timespec64_valid_strict() before
get_clock_desc() to fix it, because the "ts" is not changed
after that.

Fixes: d8794ac20a29 ("posix-clock: Fix missing timespec64 check in pc_clock_settime()")
Acked-by: Richard Cochran &lt;richardcochran@gmail.com&gt;
Signed-off-by: Jinjie Ruan &lt;ruanjinjie@huawei.com&gt;
Acked-by: Anna-Maria Behnsen &lt;anna-maria@linutronix.de&gt;
[pabeni@redhat.com: fixed commit message typo]
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If get_clock_desc() succeeds, it calls fget() for the clockid's fd,
and get the clk-&gt;rwsem read lock, so the error path should release
the lock to make the lock balance and fput the clockid's fd to make
the refcount balance and release the fd related resource.

However the below commit left the error path locked behind resulting in
unbalanced locking. Check timespec64_valid_strict() before
get_clock_desc() to fix it, because the "ts" is not changed
after that.

Fixes: d8794ac20a29 ("posix-clock: Fix missing timespec64 check in pc_clock_settime()")
Acked-by: Richard Cochran &lt;richardcochran@gmail.com&gt;
Signed-off-by: Jinjie Ruan &lt;ruanjinjie@huawei.com&gt;
Acked-by: Anna-Maria Behnsen &lt;anna-maria@linutronix.de&gt;
[pabeni@redhat.com: fixed commit message typo]
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'sched_urgent_for_v6.12_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2024-10-20T18:30:56+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-10-20T18:30:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2b4d25010d0f2e359ff34e06c120e0cee3848fc7'/>
<id>2b4d25010d0f2e359ff34e06c120e0cee3848fc7</id>
<content type='text'>
Pull scheduling fixes from Borislav Petkov:

 - Add PREEMPT_RT maintainers

 - Fix another aspect of delayed dequeued tasks wrt determining their
   state, i.e., whether they're runnable or blocked

 - Handle delayed dequeued tasks and their migration wrt PSI properly

 - Fix the situation where a delayed dequeue task gets enqueued into a
   new class, which should not happen

 - Fix a case where memory allocation would happen while the runqueue
   lock is held, which is a no-no

 - Do not over-schedule when tasks with shorter slices preempt the
   currently running task

 - Make sure delayed to deque entities are properly handled before
   unthrottling

 - Other smaller cleanups and improvements

* tag 'sched_urgent_for_v6.12_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Add an entry for PREEMPT_RT.
  sched/fair: Fix external p-&gt;on_rq users
  sched/psi: Fix mistaken CPU pressure indication after corrupted task state bug
  sched/core: Dequeue PSI signals for blocked tasks that are delayed
  sched: Fix delayed_dequeue vs switched_from_fair()
  sched/core: Disable page allocation in task_tick_mm_cid()
  sched/deadline: Use hrtick_enabled_dl() before start_hrtick_dl()
  sched/eevdf: Fix wakeup-preempt by checking cfs_rq-&gt;nr_running
  sched: Fix sched_delayed vs cfs_bandwidth
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull scheduling fixes from Borislav Petkov:

 - Add PREEMPT_RT maintainers

 - Fix another aspect of delayed dequeued tasks wrt determining their
   state, i.e., whether they're runnable or blocked

 - Handle delayed dequeued tasks and their migration wrt PSI properly

 - Fix the situation where a delayed dequeue task gets enqueued into a
   new class, which should not happen

 - Fix a case where memory allocation would happen while the runqueue
   lock is held, which is a no-no

 - Do not over-schedule when tasks with shorter slices preempt the
   currently running task

 - Make sure delayed to deque entities are properly handled before
   unthrottling

 - Other smaller cleanups and improvements

* tag 'sched_urgent_for_v6.12_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Add an entry for PREEMPT_RT.
  sched/fair: Fix external p-&gt;on_rq users
  sched/psi: Fix mistaken CPU pressure indication after corrupted task state bug
  sched/core: Dequeue PSI signals for blocked tasks that are delayed
  sched: Fix delayed_dequeue vs switched_from_fair()
  sched/core: Disable page allocation in task_tick_mm_cid()
  sched/deadline: Use hrtick_enabled_dl() before start_hrtick_dl()
  sched/eevdf: Fix wakeup-preempt by checking cfs_rq-&gt;nr_running
  sched: Fix sched_delayed vs cfs_bandwidth
</pre>
</div>
</content>
</entry>
<entry>
<title>posix-clock: Fix missing timespec64 check in pc_clock_settime()</title>
<updated>2024-10-15T00:22:43+00:00</updated>
<author>
<name>Jinjie Ruan</name>
<email>ruanjinjie@huawei.com</email>
</author>
<published>2024-10-09T07:23:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d8794ac20a299b647ba9958f6d657051fc51a540'/>
<id>d8794ac20a299b647ba9958f6d657051fc51a540</id>
<content type='text'>
As Andrew pointed out, it will make sense that the PTP core
checked timespec64 struct's tv_sec and tv_nsec range before calling
ptp-&gt;info-&gt;settime64().

As the man manual of clock_settime() said, if tp.tv_sec is negative or
tp.tv_nsec is outside the range [0..999,999,999], it should return EINVAL,
which include dynamic clocks which handles PTP clock, and the condition is
consistent with timespec64_valid(). As Thomas suggested, timespec64_valid()
only check the timespec is valid, but not ensure that the time is
in a valid range, so check it ahead using timespec64_valid_strict()
in pc_clock_settime() and return -EINVAL if not valid.

There are some drivers that use tp-&gt;tv_sec and tp-&gt;tv_nsec directly to
write registers without validity checks and assume that the higher layer
has checked it, which is dangerous and will benefit from this, such as
hclge_ptp_settime(), igb_ptp_settime_i210(), _rcar_gen4_ptp_settime(),
and some drivers can remove the checks of itself.

Cc: stable@vger.kernel.org
Fixes: 0606f422b453 ("posix clocks: Introduce dynamic clocks")
Acked-by: Richard Cochran &lt;richardcochran@gmail.com&gt;
Suggested-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Suggested-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Jinjie Ruan &lt;ruanjinjie@huawei.com&gt;
Link: https://patch.msgid.link/20241009072302.1754567-2-ruanjinjie@huawei.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As Andrew pointed out, it will make sense that the PTP core
checked timespec64 struct's tv_sec and tv_nsec range before calling
ptp-&gt;info-&gt;settime64().

As the man manual of clock_settime() said, if tp.tv_sec is negative or
tp.tv_nsec is outside the range [0..999,999,999], it should return EINVAL,
which include dynamic clocks which handles PTP clock, and the condition is
consistent with timespec64_valid(). As Thomas suggested, timespec64_valid()
only check the timespec is valid, but not ensure that the time is
in a valid range, so check it ahead using timespec64_valid_strict()
in pc_clock_settime() and return -EINVAL if not valid.

There are some drivers that use tp-&gt;tv_sec and tp-&gt;tv_nsec directly to
write registers without validity checks and assume that the higher layer
has checked it, which is dangerous and will benefit from this, such as
hclge_ptp_settime(), igb_ptp_settime_i210(), _rcar_gen4_ptp_settime(),
and some drivers can remove the checks of itself.

Cc: stable@vger.kernel.org
Fixes: 0606f422b453 ("posix clocks: Introduce dynamic clocks")
Acked-by: Richard Cochran &lt;richardcochran@gmail.com&gt;
Suggested-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Suggested-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Jinjie Ruan &lt;ruanjinjie@huawei.com&gt;
Link: https://patch.msgid.link/20241009072302.1754567-2-ruanjinjie@huawei.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched/fair: Fix external p-&gt;on_rq users</title>
<updated>2024-10-14T07:14:35+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2024-10-10T09:38:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cd9626e9ebc77edec33023fe95dab4b04ffc819d'/>
<id>cd9626e9ebc77edec33023fe95dab4b04ffc819d</id>
<content type='text'>
Sean noted that ever since commit 152e11f6df29 ("sched/fair: Implement
delayed dequeue") KVM's preemption notifiers have started
mis-classifying preemption vs blocking.

Notably p-&gt;on_rq is no longer sufficient to determine if a task is
runnable or blocked -- the aforementioned commit introduces tasks that
remain on the runqueue even through they will not run again, and
should be considered blocked for many cases.

Add the task_is_runnable() helper to classify things and audit all
external users of the p-&gt;on_rq state. Also add a few comments.

Fixes: 152e11f6df29 ("sched/fair: Implement delayed dequeue")
Reported-by: Sean Christopherson &lt;seanjc@google.com&gt;
Tested-by: Sean Christopherson &lt;seanjc@google.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lkml.kernel.org/r/20241010091843.GK33184@noisy.programming.kicks-ass.net
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Sean noted that ever since commit 152e11f6df29 ("sched/fair: Implement
delayed dequeue") KVM's preemption notifiers have started
mis-classifying preemption vs blocking.

Notably p-&gt;on_rq is no longer sufficient to determine if a task is
runnable or blocked -- the aforementioned commit introduces tasks that
remain on the runqueue even through they will not run again, and
should be considered blocked for many cases.

Add the task_is_runnable() helper to classify things and audit all
external users of the p-&gt;on_rq state. Also add a few comments.

Fixes: 152e11f6df29 ("sched/fair: Implement delayed dequeue")
Reported-by: Sean Christopherson &lt;seanjc@google.com&gt;
Tested-by: Sean Christopherson &lt;seanjc@google.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lkml.kernel.org/r/20241010091843.GK33184@noisy.programming.kicks-ass.net
</pre>
</div>
</content>
</entry>
<entry>
<title>[tree-wide] finally take no_llseek out</title>
<updated>2024-09-27T15:18:43+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2024-09-27T01:56:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cb787f4ac0c2e439ea8d7e6387b925f74576bdf8'/>
<id>cb787f4ac0c2e439ea8d7e6387b925f74576bdf8</id>
<content type='text'>
no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

  At -rc1 we'll need do a mechanical removal of no_llseek -

  git grep -l -w no_llseek | grep -v porting.rst | while read i; do
	sed -i '/\&lt;no_llseek\&gt;/d' $i
  done

  would do it.

Unfortunately, that hadn't been done.  Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
	.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
no_llseek had been defined to NULL two years ago, in commit 868941b14441
("fs: remove no_llseek")

To quote that commit,

  At -rc1 we'll need do a mechanical removal of no_llseek -

  git grep -l -w no_llseek | grep -v porting.rst | while read i; do
	sed -i '/\&lt;no_llseek\&gt;/d' $i
  done

  would do it.

Unfortunately, that hadn't been done.  Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
	.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2024-09-19T13:55:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-09-19T13:55:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2004cef11ea072838f99bd95cefa5c8e45df0847'/>
<id>2004cef11ea072838f99bd95cefa5c8e45df0847</id>
<content type='text'>
Pull scheduler updates from Ingo Molnar:

 - Implement the SCHED_DEADLINE server infrastructure - Daniel Bristot
   de Oliveira's last major contribution to the kernel:

     "SCHED_DEADLINE servers can help fixing starvation issues of low
      priority tasks (e.g., SCHED_OTHER) when higher priority tasks
      monopolize CPU cycles. Today we have RT Throttling; DEADLINE
      servers should be able to replace and improve that."

   (Daniel Bristot de Oliveira, Peter Zijlstra, Joel Fernandes, Youssef
   Esmat, Huang Shijie)

 - Preparatory changes for sched_ext integration:
     - Use set_next_task(.first) where required
     - Fix up set_next_task() implementations
     - Clean up DL server vs. core sched
     - Split up put_prev_task_balance()
     - Rework pick_next_task()
     - Combine the last put_prev_task() and the first set_next_task()
     - Rework dl_server
     - Add put_prev_task(.next)

   (Peter Zijlstra, with a fix by Tejun Heo)

 - Complete the EEVDF transition and refine EEVDF scheduling:
     - Implement delayed dequeue
     - Allow shorter slices to wakeup-preempt
     - Use sched_attr::sched_runtime to set request/slice suggestion
     - Document the new feature flags
     - Remove unused and duplicate-functionality fields
     - Simplify &amp; unify pick_next_task_fair()
     - Misc debuggability enhancements

   (Peter Zijlstra, with fixes/cleanups by Dietmar Eggemann, Valentin
   Schneider and Chuyi Zhou)

 - Initialize the vruntime of a new task when it is first enqueued,
   resulting in significant decrease in latency of newly woken tasks
   (Zhang Qiao)

 - Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
   (K Prateek Nayak, Peter Zijlstra)

 - Clean up and clarify the usage of Clean up usage of rt_task()
   (Qais Yousef)

 - Preempt SCHED_IDLE entities in strict cgroup hierarchies
   (Tianchen Ding)

 - Clarify the documentation of time units for deadline scheduler
   parameters (Christian Loehle)

 - Remove the HZ_BW chicken-bit feature flag introduced a year ago,
   the original change seems to be working fine (Phil Auld)

 - Misc fixes and cleanups (Chen Yu, Dan Carpenter, Huang Shijie,
   Peilin He, Qais Yousefm and Vincent Guittot)

* tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  sched/cpufreq: Use NSEC_PER_MSEC for deadline task
  cpufreq/cppc: Use NSEC_PER_MSEC for deadline task
  sched/deadline: Clarify nanoseconds in uapi
  sched/deadline: Convert schedtool example to chrt
  sched/debug: Fix the runnable tasks output
  sched: Fix sched_delayed vs sched_core
  kernel/sched: Fix util_est accounting for DELAY_DEQUEUE
  kthread: Fix task state in kthread worker if being frozen
  sched/pelt: Use rq_clock_task() for hw_pressure
  sched/fair: Move effective_cpu_util() and effective_cpu_util() in fair.c
  sched/core: Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
  sched: Add put_prev_task(.next)
  sched: Rework dl_server
  sched: Combine the last put_prev_task() and the first set_next_task()
  sched: Rework pick_next_task()
  sched: Split up put_prev_task_balance()
  sched: Clean up DL server vs core sched
  sched: Fixup set_next_task() implementations
  sched: Use set_next_task(.first) where required
  sched/fair: Properly deactivate sched_delayed task upon class change
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull scheduler updates from Ingo Molnar:

 - Implement the SCHED_DEADLINE server infrastructure - Daniel Bristot
   de Oliveira's last major contribution to the kernel:

     "SCHED_DEADLINE servers can help fixing starvation issues of low
      priority tasks (e.g., SCHED_OTHER) when higher priority tasks
      monopolize CPU cycles. Today we have RT Throttling; DEADLINE
      servers should be able to replace and improve that."

   (Daniel Bristot de Oliveira, Peter Zijlstra, Joel Fernandes, Youssef
   Esmat, Huang Shijie)

 - Preparatory changes for sched_ext integration:
     - Use set_next_task(.first) where required
     - Fix up set_next_task() implementations
     - Clean up DL server vs. core sched
     - Split up put_prev_task_balance()
     - Rework pick_next_task()
     - Combine the last put_prev_task() and the first set_next_task()
     - Rework dl_server
     - Add put_prev_task(.next)

   (Peter Zijlstra, with a fix by Tejun Heo)

 - Complete the EEVDF transition and refine EEVDF scheduling:
     - Implement delayed dequeue
     - Allow shorter slices to wakeup-preempt
     - Use sched_attr::sched_runtime to set request/slice suggestion
     - Document the new feature flags
     - Remove unused and duplicate-functionality fields
     - Simplify &amp; unify pick_next_task_fair()
     - Misc debuggability enhancements

   (Peter Zijlstra, with fixes/cleanups by Dietmar Eggemann, Valentin
   Schneider and Chuyi Zhou)

 - Initialize the vruntime of a new task when it is first enqueued,
   resulting in significant decrease in latency of newly woken tasks
   (Zhang Qiao)

 - Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
   (K Prateek Nayak, Peter Zijlstra)

 - Clean up and clarify the usage of Clean up usage of rt_task()
   (Qais Yousef)

 - Preempt SCHED_IDLE entities in strict cgroup hierarchies
   (Tianchen Ding)

 - Clarify the documentation of time units for deadline scheduler
   parameters (Christian Loehle)

 - Remove the HZ_BW chicken-bit feature flag introduced a year ago,
   the original change seems to be working fine (Phil Auld)

 - Misc fixes and cleanups (Chen Yu, Dan Carpenter, Huang Shijie,
   Peilin He, Qais Yousefm and Vincent Guittot)

* tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  sched/cpufreq: Use NSEC_PER_MSEC for deadline task
  cpufreq/cppc: Use NSEC_PER_MSEC for deadline task
  sched/deadline: Clarify nanoseconds in uapi
  sched/deadline: Convert schedtool example to chrt
  sched/debug: Fix the runnable tasks output
  sched: Fix sched_delayed vs sched_core
  kernel/sched: Fix util_est accounting for DELAY_DEQUEUE
  kthread: Fix task state in kthread worker if being frozen
  sched/pelt: Use rq_clock_task() for hw_pressure
  sched/fair: Move effective_cpu_util() and effective_cpu_util() in fair.c
  sched/core: Introduce SM_IDLE and an idle re-entry fast-path in __schedule()
  sched: Add put_prev_task(.next)
  sched: Rework dl_server
  sched: Combine the last put_prev_task() and the first set_next_task()
  sched: Rework pick_next_task()
  sched: Split up put_prev_task_balance()
  sched: Clean up DL server vs core sched
  sched: Fixup set_next_task() implementations
  sched: Use set_next_task(.first) where required
  sched/fair: Properly deactivate sched_delayed task upon class change
  ...
</pre>
</div>
</content>
</entry>
</feed>
