Commit 58329c43 authored by Herbert Xu's avatar Herbert Xu
Browse files

padata: Disable BH when taking works lock on MT path 



As the old padata code can execute in softirq context, disable
softirqs for the new padata_do_mutithreaded code too as otherwise
lockdep will get antsy.

Reported-by: default avatar <syzbot+0cb5bb0f4bf9e79db3b3@syzkaller.appspotmail.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 42c2d7d0

kernel/padata.c

+4 −4
Original line number Diff line number Diff line
@@ -106,7 +106,7 @@ static int __init padata_work_alloc_mt(int nworks, void *data, 
{

	int i;



	spin_lock(&padata_works_lock);

	spin_lock_bh(&padata_works_lock);

	/* Start at 1 because the current task participates in the job. */

	for (i = 1; i < nworks; ++i) {

		struct padata_work *pw = padata_work_alloc();
@@ -116,7 +116,7 @@ static int __init padata_work_alloc_mt(int nworks, void *data, 
		padata_work_init(pw, padata_mt_helper, data, 0);

		list_add(&pw->pw_list, head);

	}

	spin_unlock(&padata_works_lock);

	spin_unlock_bh(&padata_works_lock);



	return i;

}
@@ -134,12 +134,12 @@ static void __init padata_works_free(struct list_head *works) 
	if (list_empty(works))

		return;



	spin_lock(&padata_works_lock);

	spin_lock_bh(&padata_works_lock);

	list_for_each_entry_safe(cur, next, works, pw_list) {

		list_del(&cur->pw_list);

		padata_work_free(cur);

	}

	spin_unlock(&padata_works_lock);

	spin_unlock_bh(&padata_works_lock);

}



static void padata_parallel_worker(struct work_struct *parallel_work)