From: Li Lingfeng <lilingfeng@huaweicloud.com>
To: song@kernel.org
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org,
yukuai3@huawei.com, yukuai1@huaweicloud.com, linan122@huawei.com,
yi.zhang@huawei.com, yangerkun@huawei.com,
lilingfeng@huaweicloud.com, lilingfeng3@huawei.com
Subject: [PATCH] md: use RCU lock to protect traversal in md_spares_need_change()
Date: Thu, 4 Jan 2024 21:36:29 +0800 [thread overview]
Message-ID: <20240104133629.1277517-1-lilingfeng@huaweicloud.com> (raw)
From: Li Lingfeng <lilingfeng3@huawei.com>
Since md_start_sync() will be called without the protect of mddev_lock,
and it can run concurrently with array reconfiguration, traversal of rdev
in it should be protected by RCU lock.
Commit bc08041b32ab ("md: suspend array in md_start_sync() if array need
reconfiguration") added md_spares_need_change() to md_start_sync(),
casusing use of rdev without any protection.
Fix this by adding RCU lock in md_spares_need_change().
Fixes: bc08041b32ab ("md: suspend array in md_start_sync() if array need reconfiguration")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
---
drivers/md/md.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 9bdd57324c37..902b43b65052 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -9228,9 +9228,14 @@ static bool md_spares_need_change(struct mddev *mddev)
{
struct md_rdev *rdev;
- rdev_for_each(rdev, mddev)
- if (rdev_removeable(rdev) || rdev_addable(rdev))
+ rcu_read_lock();
+ rdev_for_each_rcu(rdev, mddev) {
+ if (rdev_removeable(rdev) || rdev_addable(rdev)) {
+ rcu_read_unlock();
return true;
+ }
+ }
+ rcu_read_unlock();
return false;
}
--
2.31.1
next reply other threads:[~2024-01-04 13:39 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-04 13:36 Li Lingfeng [this message]
2024-01-30 7:11 ` [PATCH] md: use RCU lock to protect traversal in md_spares_need_change() Song Liu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240104133629.1277517-1-lilingfeng@huaweicloud.com \
--to=lilingfeng@huaweicloud.com \
--cc=lilingfeng3@huawei.com \
--cc=linan122@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-raid@vger.kernel.org \
--cc=song@kernel.org \
--cc=yangerkun@huawei.com \
--cc=yi.zhang@huawei.com \
--cc=yukuai1@huaweicloud.com \
--cc=yukuai3@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).