Commit 9cb38381 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'block-6.4-2023-06-23' of git://git.kernel.dk/linux 

Pull block fix from Jens Axboe:
 "It's apparently the week of 'fixup something from last week', because
  the same is true for this block pull request.

  Fix up a lock grab that needs to be IRQ saving, rather than just IRQ
  disabling, in the block cgroup code"

* tag 'block-6.4-2023-06-23' of git://git.kernel.dk/linux:
  block: make sure local irq is disabled when calling __blkcg_rstat_flush
parents 917b3c7c 9c39b7a9

block/blk-cgroup.c

+3 −2
Original line number Diff line number Diff line
@@ -970,6 +970,7 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) 
	struct llist_head *lhead = per_cpu_ptr(blkcg->lhead, cpu);

	struct llist_node *lnode;

	struct blkg_iostat_set *bisc, *next_bisc;

	unsigned long flags;



	rcu_read_lock();
@@ -983,7 +984,7 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) 
	 * When flushing from cgroup, cgroup_rstat_lock is always held, so

	 * this lock won't cause contention most of time.

	 */

	raw_spin_lock(&blkg_stat_lock);

	raw_spin_lock_irqsave(&blkg_stat_lock, flags);



	/*

	 * Iterate only the iostat_cpu's queued in the lockless list.
@@ -1009,7 +1010,7 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) 
			blkcg_iostat_update(parent, &blkg->iostat.cur,

					    &blkg->iostat.last);

	}

	raw_spin_unlock(&blkg_stat_lock);

	raw_spin_unlock_irqrestore(&blkg_stat_lock, flags);

out:

	rcu_read_unlock();

}