linux-kernel - [PATCH v2 0/4] RCU dyntick nesting counter cleanups

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 28 Mar 2020 18:16:59 -0400
From:   "Joel Fernandes (Google)" <joel@...lfernandes.org>
To:     linux-kernel@...r.kernel.org
Cc:     "Joel Fernandes (Google)" <joel@...lfernandes.org>,
        Andy Lutomirski <luto@...nel.org>,
        Frederic Weisbecker <fweisbec@...il.com>, frextrite@...il.com,
        Ingo Molnar <mingo@...hat.com>,
        Josh Triplett <josh@...htriplett.org>, kernel-team@...roid.com,
        Lai Jiangshan <jiangshanlai@...il.com>,
        madhuparnabhowmik04@...il.com,
        Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
        "Paul E. McKenney" <paulmck@...nel.org>, peterz@...radead.org,
        Petr Mladek <pmladek@...e.com>, rcu@...r.kernel.org,
        rostedt@...dmis.org, tglx@...utronix.de, vpillai@...italocean.com
Subject: [PATCH v2 0/4] RCU dyntick nesting counter cleanups

These patches clean up the usage of dynticks nesting counters simplifying the
code, while preserving the usecases.

It is a much needed simplification, makes the code less confusing, and prevents
future bugs such as those that arise from forgetting that the
dynticks_nmi_nesting counter is not a simple counter and can be "crowbarred" in
common situations.

rcutorture testing with all TREE RCU configurations succeed with
CONFIG_RCU_EQS_DEBUG=y and CONFIG_PROVE_LOCKING=y.

v1->v2:
- Rebase on v5.6-rc6

Joel Fernandes (Google) (4):
Revert b8c17e6664c4 ("rcu: Maintain special bits at bottom of
->dynticks counter")
rcu/tree: Add better tracing for dyntick-idle
rcu/tree: Clean up dynticks counter usage
rcu/tree: Remove dynticks_nmi_nesting counter

.../Data-Structures/Data-Structures.rst       |  31 +--
Documentation/RCU/stallwarn.txt               |   6 +-
include/linux/rcutiny.h                       |   3 -
include/trace/events/rcu.h                    |  29 +--
kernel/rcu/rcu.h                              |   4 -
kernel/rcu/tree.c                             | 188 +++++++-----------
kernel/rcu/tree.h                             |   4 +-
kernel/rcu/tree_stall.h                       |   4 +-
8 files changed, 105 insertions(+), 164 deletions(-)

--
2.26.0.rc2.310.g2932bb562d-goog