diff options
author | Li Lingfeng <lilingfeng3@huawei.com> | 2023-12-29 15:05:00 +0800 |
---|---|---|
committer | Song Liu <song@kernel.org> | 2024-02-05 15:23:58 -0800 |
commit | 9cfcf99e7ed613e6b3697e1c1034a24487ec3154 (patch) | |
tree | c13b5cef52ef3e3bf9d144abe0b48e778aeb433c /drivers/md/md.c | |
parent | faeaf210a559eb05bc1a294082d100d01c49a1e9 (diff) | |
download | lwn-9cfcf99e7ed613e6b3697e1c1034a24487ec3154.tar.gz lwn-9cfcf99e7ed613e6b3697e1c1034a24487ec3154.zip |
md: get rdev->mddev with READ_ONCE()
Users may get rdev->mddev by sysfs while rdev is releasing.
So use both READ_ONCE() and WRITE_ONCE() to prevent load/store tearing
and to read/write mddev atomically.
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231229070500.3602712-1-lilingfeng@huaweicloud.com
Diffstat (limited to 'drivers/md/md.c')
-rw-r--r-- | drivers/md/md.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 0b132ee2672e..5eff8e84cddf 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2591,7 +2591,7 @@ static void md_kick_rdev_from_array(struct md_rdev *rdev) list_del_rcu(&rdev->same_set); pr_debug("md: unbind<%pg>\n", rdev->bdev); mddev_destroy_serial_pool(rdev->mddev, rdev); - rdev->mddev = NULL; + WRITE_ONCE(rdev->mddev, NULL); sysfs_remove_link(&rdev->kobj, "block"); sysfs_put(rdev->sysfs_state); sysfs_put(rdev->sysfs_unack_badblocks); @@ -3664,7 +3664,7 @@ rdev_attr_store(struct kobject *kobj, struct attribute *attr, struct kernfs_node *kn = NULL; bool suspend = false; ssize_t rv; - struct mddev *mddev = rdev->mddev; + struct mddev *mddev = READ_ONCE(rdev->mddev); if (!entry->store) return -EIO; |