From patchwork Wed Jun 29 13:20:12 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [Natty,SRU] UBUNTU: SAUCE: fix yama_ptracer_del lockdep warning Date: Wed, 29 Jun 2011 03:20:12 -0000 From: Ming Lei X-Patchwork-Id: 102603 Message-Id: <20110629212012.4377f687@tom-ThinkPad-T410> To: kernel-team@lists.ubuntu.com >From 7e597da6c9b6aea298ac8fdf93951a4d4b259d68 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Wed, 29 Jun 2011 19:06:25 +0800 Subject: [PATCH] [Natty SRU] UBUNTU: SAUCE: fix yama_ptracer_del lockdep warning yama_ptracer_del can be called in softirq context, also can be run in common process context, so take spin_lock_bh in yama_ptracer_del to fix it, othewise deadlock may be produced. SRU Justification: Impact: - lockdep warning is triggered if lockdep config options are enabled - probably deadlock can be produced in yama_ptracer_del path Fix: - After applying the patch, lockdep warning is fixefd BugLink: http://bugs.launchpad.net/bugs/791019 Signed-off-by: Ming Lei --- security/yama/yama_lsm.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c index 7c3591a..927e6ad 100644 --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -82,7 +82,7 @@ static void yama_ptracer_del(struct task_struct *tracer, struct ptrace_relation *relation; struct list_head *list, *safe; - spin_lock(&ptracer_relations_lock); + spin_lock_bh(&ptracer_relations_lock); list_for_each_safe(list, safe, &ptracer_relations) { relation = list_entry(list, struct ptrace_relation, node); if (relation->tracee == tracee || @@ -91,7 +91,7 @@ static void yama_ptracer_del(struct task_struct *tracer, kfree(relation); } } - spin_unlock(&ptracer_relations_lock); + spin_unlock_bh(&ptracer_relations_lock); } /**