Unverified Commit 6a6cc2b6 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!15050 brd: fix AA deadlock for concurrent brd_probe() 

Merge Pull Request from: @ci-robot 
 
PR sync from: Yu Kuai <yukuai3@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/YBGNT3DPVUDRJGRBZAJZZ3JHQ6UAZJRO/ 
 
https://gitee.com/openeuler/kernel/issues/IBIWBN 
 
Link:https://gitee.com/openeuler/kernel/pulls/15050

 

Reviewed-by: default avatarHou Tao <houtao1@huawei.com>
Reviewed-by: default avatarYuan Can <yuancan@huawei.com>
Signed-off-by: default avatarYuan Can <yuancan@huawei.com>
parents e7e24815 f6920411

drivers/block/brd.c

+5 −18
Original line number Diff line number Diff line
@@ -418,15 +418,13 @@ static void brd_free(struct brd_device *brd) 
	kfree(brd);

}



static struct brd_device *brd_init_one(int i, bool *new)

static void brd_init_one(int i)

{

	struct brd_device *brd;



	*new = false;

	list_for_each_entry(brd, &brd_devices, brd_list) {

	list_for_each_entry(brd, &brd_devices, brd_list)

		if (brd->brd_number == i)

			goto out;

	}

			return;



	brd = brd_alloc(i);

	if (brd) {
@@ -434,9 +432,6 @@ static struct brd_device *brd_init_one(int i, bool *new) 
		add_disk(brd->brd_disk);

		list_add_tail(&brd->brd_list, &brd_devices);

	}

	*new = true;

out:

	return brd;

}



static void brd_del_one(struct brd_device *brd)
@@ -448,19 +443,11 @@ static void brd_del_one(struct brd_device *brd) 


static struct kobject *brd_probe(dev_t dev, int *part, void *data)

{

	struct brd_device *brd;

	struct kobject *kobj;

	bool new;



	mutex_lock(&brd_devices_mutex);

	brd = brd_init_one(MINOR(dev) / max_part, &new);

	kobj = brd ? get_disk_and_module(brd->brd_disk) : NULL;

	brd_init_one(MINOR(dev) / max_part);

	mutex_unlock(&brd_devices_mutex);



	if (new)

		*part = 0;



	return kobj;

	return NULL;

}



static inline void brd_check_and_reset_par(void)