From: Jens Axboe Date: Mon, 30 Oct 2006 18:07:48 +0000 (+0100) Subject: [PATCH] CFQ: use irq safe locking in cfq_cic_link() X-Git-Tag: v2.6.19-rc4~21 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0261d6886eb5822867a5310dc1e4479b940a1942;p=linux-2.6 [PATCH] CFQ: use irq safe locking in cfq_cic_link() If cfq_set_request() is called for a new process AND a non-fs io request (so that __GFP_WAIT may not be set), cfq_cic_link() may use spin_lock_irq() and spin_unlock_irq() with interrupts already disabled. Fix is to always use irq safe locking in cfq_cic_link() Acked-By: Arjan van de Ven Acked-by: Ingo Molnar Signed-off-by: Jens Axboe Signed-off-by: Linus Torvalds --- diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index d3d76136f5..5c3da894a5 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1362,6 +1362,7 @@ cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, struct rb_node **p; struct rb_node *parent; struct cfq_io_context *__cic; + unsigned long flags; void *k; cic->ioc = ioc; @@ -1391,9 +1392,9 @@ restart: rb_link_node(&cic->rb_node, parent, p); rb_insert_color(&cic->rb_node, &ioc->cic_root); - spin_lock_irq(cfqd->queue->queue_lock); + spin_lock_irqsave(cfqd->queue->queue_lock, flags); list_add(&cic->queue_list, &cfqd->cic_list); - spin_unlock_irq(cfqd->queue->queue_lock); + spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); } /*