[PATCH] md: avoid a deadlock when removing a device from an md array via sysfs (5792a285) · Commits · 戴 / test

drivers/md/md.c

+15 −1

Original line number	Diff line number	Diff line
		@@ -1378,6 +1378,12 @@ static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
		return err;
		}

		static void delayed_delete(struct work_struct *ws)
		{
		mdk_rdev_t *rdev = container_of(ws, mdk_rdev_t, del_work);
		kobject_del(&rdev->kobj);
		}

		static void unbind_rdev_from_array(mdk_rdev_t * rdev)
		{
		char b[BDEVNAME_SIZE];
		@@ -1390,7 +1396,12 @@ static void unbind_rdev_from_array(mdk_rdev_t * rdev)
		printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
		rdev->mddev = NULL;
		sysfs_remove_link(&rdev->kobj, "block");
		kobject_del(&rdev->kobj);

		/* We need to delay this, otherwise we can deadlock when
		* writing to 'remove' to "dev/state"
		*/
		INIT_WORK(&rdev->del_work, delayed_delete);
		schedule_work(&rdev->del_work);
		}

		/*
		@@ -3389,6 +3400,9 @@ static int do_md_stop(mddev_t * mddev, int mode)
		sysfs_remove_link(&mddev->kobj, nm);
		}

		/* make sure all delayed_delete calls have finished */
		flush_scheduled_work();

		export_array(mddev);

		mddev->array_size = 0;

+1 −0

Original line number	Diff line number	Diff line
		@@ -104,6 +104,7 @@ struct mdk_rdev_s
		* for reporting to userspace and storing
		* in superblock.
		*/
		struct work_struct del_work; /* used for delayed sysfs removal */
		};

		struct mddev_s