linux-kernel - [PATCH] blk-cgroup: Call cgroup

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: <1331582478-2259-1-git-send-email-levinsasha928@gmail.com>
Date:	Mon, 12 Mar 2012 16:01:18 -0400
From:	Sasha Levin <levinsasha928@...il.com>
To:	axboe@...nel.dk
Cc:	tj@...nel.org, linux-kernel@...r.kernel.org,
	Sasha Levin <levinsasha928@...il.com>
Subject: [PATCH] blk-cgroup: Call cgroup_path only under cgroup lock

Since we can't keep rcu read lock during blkg_alloc(), we currently
call cgroup_path() without any locks at all.

This patch adds cgroup locking before calling cgroup_path.

This also fixes a lockdep warning on boot.

Signed-off-by: Sasha Levin <levinsasha928@...il.com>
---
 block/blk-cgroup.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index cb6b176..b5f539c 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -508,7 +508,9 @@ static struct blkio_group *blkg_alloc(struct blkio_cgroup *blkcg,
 	INIT_LIST_HEAD(&blkg->q_node);
 	blkg->blkcg = blkcg;
 	blkg->refcnt = 1;
+	cgroup_lock();
 	cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path));
+	cgroup_unlock();
 
 	for (i = 0; i < BLKIO_NR_POLICIES; i++) {
 		struct blkio_policy_type *pol = blkio_policy[i];
-- 
1.7.8.4

--
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/