linux-kernel - [PATCH 0/2 v6] lockdep: add support for queued rwlock

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]

Message-Id: <1406659999-13974-1-git-send-email-Waiman.Long@hp.com>
Date:	Tue, 29 Jul 2014 14:53:17 -0400
From:	Waiman Long <Waiman.Long@...com>
To:	Ingo Molnar <mingo@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Maarten Lankhorst <maarten.lankhorst@...onical.com>,
	Rik van Riel <riel@...hat.com>
Cc:	linux-kernel@...r.kernel.org, Scott J Norton <scott.norton@...com>,
	Fengguang Wu <fengguang.wu@...el.com>,
	Waiman Long <Waiman.Long@...com>
Subject: [PATCH 0/2 v6]  lockdep: add support for queued rwlock

v5->v6:
 - Unconditionally disallow the use of recursive read-lock in process
   context.
 - Promote read state 3 to 2 when in interrupt context instead of
   doing additional check in check_deadlock().
 - Fix some comments in locking-selftest.c.

v4->v5:
 - Add patch 2 to update the locking selftest code to handle recursive
   read_lock correctly. Patch 1 has no change.

v3->v4:
 - Document the new read state and move the conditional compilation code
   to lockdep.h.

v2->v3:
 - Add a new read mode (3) for rwlock (used in
   lock_acquire_shared_cond_recursive()) to avoid conflict with other
   use cases of lock_acquire_shared_recursive().

v1->v2:
 - Use less conditional & make it easier to read

With the merging of qrwlock into 3.16, it was found that the btrfs
filesystem hanged readily. A fix was devised and merged into rc2 and
the use of recursive read_lock call was part of the problem.

This patch series addes code to the lockdep subsystem to catch this
kind of recursive read_lock calls in kernel code. It also updates
the locking selftest to handle recursive read_lock correctly so that
it won't complain about test failures.

Waiman Long (2):
  locking/lockdep: Restrict the use of recursive read_lock() with
    qrwlock
  locking/selftest: Support queued rwlock

 include/linux/lockdep.h  |   10 +++++++++-
 kernel/locking/lockdep.c |    6 ++++++
 lib/locking-selftest.c   |   12 ++++++------
 3 files changed, 21 insertions(+), 7 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/