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* [PATCH 4.4 00/11] Fix a potential infinite loop in RT futex-pi scenarios
@ 2021-08-02 13:46 Zhen Lei
  2021-08-02 13:46 ` [PATCH 4.4 01/11] futex: Rename free_pi_state() to put_pi_state() Zhen Lei
                   ` (11 more replies)
  0 siblings, 12 replies; 15+ messages in thread
From: Zhen Lei @ 2021-08-02 13:46 UTC (permalink / raw)
  To: Greg Kroah-Hartman, stable
  Cc: Zhen Lei, Anna-Maria Gleixner, Mike Galbraith, Sasha Levin,
	Ingo Molnar, Peter Zijlstra, Thomas Gleixner, linux-kernel

Commit 73d786bd043e "futex: Rework inconsistent rt_mutex/futex_q state"
mentions that it could cause an infinite loop, and will fix it in the later
patches:
bebe5b514345f09 futex: Futex_unlock_pi() determinism
cfafcd117da0216 futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()

But at the moment they're not backported. In a single-core environment, the
probability of triggering is high.

I also backported commit b4abf91047cf ("rtmutex: Make wait_lock irq safe"),
it fixes a potential deadlock problem. Although it hasn't actually been
triggered in our environment at the moment.

Other patches are used to resolve conflicts or fix problems caused by new
patches.


Anna-Maria Gleixner (1):
  rcu: Update documentation of rcu_read_unlock()

Mike Galbraith (1):
  futex: Handle transient "ownerless" rtmutex state correctly

Peter Zijlstra (6):
  futex: Cleanup refcounting
  futex,rt_mutex: Introduce rt_mutex_init_waiter()
  futex: Pull rt_mutex_futex_unlock() out from under hb->lock
  futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()
  futex: Futex_unlock_pi() determinism
  futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock()

Thomas Gleixner (3):
  futex: Rename free_pi_state() to put_pi_state()
  rtmutex: Make wait_lock irq safe
  futex: Avoid freeing an active timer

 include/linux/rcupdate.h        |   4 +-
 kernel/futex.c                  | 245 +++++++++++++++++++++-----------
 kernel/locking/rtmutex.c        | 185 +++++++++++++-----------
 kernel/locking/rtmutex_common.h |   2 +-
 4 files changed, 262 insertions(+), 174 deletions(-)

-- 
2.26.0.106.g9fadedd


^ permalink raw reply	[flat|nested] 15+ messages in thread
* [PATCH 4.4 00/11] 4.4.280-rc1 review
@ 2021-08-08  7:22 Greg Kroah-Hartman
  2021-08-08  7:22 ` [PATCH 4.4 05/11] futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock() Greg Kroah-Hartman
  0 siblings, 1 reply; 15+ messages in thread
From: Greg Kroah-Hartman @ 2021-08-08  7:22 UTC (permalink / raw)
  To: linux-kernel
  Cc: Greg Kroah-Hartman, torvalds, akpm, linux, shuah, patches,
	lkft-triage, pavel, jonathanh, f.fainelli, stable

This is the start of the stable review cycle for the 4.4.280 release.
There are 11 patches in this series, all will be posted as a response
to this one.  If anyone has any issues with these being applied, please
let me know.

Responses should be made by Tue, 10 Aug 2021 07:22:11 +0000.
Anything received after that time might be too late.

The whole patch series can be found in one patch at:
	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.4.280-rc1.gz
or in the git tree and branch at:
	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.4.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Linux 4.4.280-rc1

Anna-Maria Gleixner <anna-maria@linutronix.de>
    rcu: Update documentation of rcu_read_unlock()

Peter Zijlstra <peterz@infradead.org>
    futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock()

Thomas Gleixner <tglx@linutronix.de>
    futex: Avoid freeing an active timer

Mike Galbraith <efault@gmx.de>
    futex: Handle transient "ownerless" rtmutex state correctly

Thomas Gleixner <tglx@linutronix.de>
    rtmutex: Make wait_lock irq safe

Peter Zijlstra <peterz@infradead.org>
    futex: Futex_unlock_pi() determinism

Peter Zijlstra <peterz@infradead.org>
    futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()

Peter Zijlstra <peterz@infradead.org>
    futex: Pull rt_mutex_futex_unlock() out from under hb->lock

Peter Zijlstra <peterz@infradead.org>
    futex,rt_mutex: Introduce rt_mutex_init_waiter()

Peter Zijlstra <peterz@infradead.org>
    futex: Cleanup refcounting

Thomas Gleixner <tglx@linutronix.de>
    futex: Rename free_pi_state() to put_pi_state()


-------------

Diffstat:

 Makefile                        |   4 +-
 include/linux/rcupdate.h        |   4 +-
 kernel/futex.c                  | 245 ++++++++++++++++++++++++++--------------
 kernel/locking/rtmutex.c        | 185 ++++++++++++++++--------------
 kernel/locking/rtmutex_common.h |   2 +-
 5 files changed, 264 insertions(+), 176 deletions(-)



^ permalink raw reply	[flat|nested] 15+ messages in thread

end of thread, other threads:[~2021-08-08  7:23 UTC | newest]

Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-02 13:46 [PATCH 4.4 00/11] Fix a potential infinite loop in RT futex-pi scenarios Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 01/11] futex: Rename free_pi_state() to put_pi_state() Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 02/11] futex: Cleanup refcounting Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 03/11] futex,rt_mutex: Introduce rt_mutex_init_waiter() Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 04/11] futex: Pull rt_mutex_futex_unlock() out from under hb->lock Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 05/11] futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock() Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 06/11] futex: Futex_unlock_pi() determinism Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 07/11] rtmutex: Make wait_lock irq safe Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 08/11] futex: Handle transient "ownerless" rtmutex state correctly Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 09/11] futex: Avoid freeing an active timer Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 10/11] futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock() Zhen Lei
2021-08-02 13:46 ` [PATCH 4.4 11/11] rcu: Update documentation of rcu_read_unlock() Zhen Lei
2021-08-03  0:53 ` [PATCH 4.4 00/11] Fix a potential infinite loop in RT futex-pi scenarios Joe Korty
2021-08-08  6:46   ` Greg Kroah-Hartman
2021-08-08  7:22 [PATCH 4.4 00/11] 4.4.280-rc1 review Greg Kroah-Hartman
2021-08-08  7:22 ` [PATCH 4.4 05/11] futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock() Greg Kroah-Hartman

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