From 3076212f8d3d9fe4d7b11c6b560c0f424edfcb4e Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Thu, 29 Mar 2007 01:20:30 -0700 Subject: [PATCH] [PATCH] uml: irq locking fixes As the comment immediately preceding this points out, this list is changed in irq context, so it needs to be protected with spin_lock_irqsave in process context when it is processed. Sometimes, gcc should just compile the comments and forget the code. The IRQ side of this was better, in the sense that it blocked and unblocked interrupts, but it still should have saved and restored them. Signed-off-by: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/drivers/chan_kern.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c index 7b8baf146a..9fdfad6495 100644 --- a/arch/um/drivers/chan_kern.c +++ b/arch/um/drivers/chan_kern.c @@ -236,11 +236,11 @@ void free_irqs(void) struct chan *chan; LIST_HEAD(list); struct list_head *ele; + unsigned long flags; - spin_lock_irq(&irqs_to_free_lock); + spin_lock_irqsave(&irqs_to_free_lock, flags); list_splice_init(&irqs_to_free, &list); - INIT_LIST_HEAD(&irqs_to_free); - spin_unlock_irq(&irqs_to_free_lock); + spin_unlock_irqrestore(&irqs_to_free_lock, flags); list_for_each(ele, &list){ chan = list_entry(ele, struct chan, free_list); @@ -255,13 +255,15 @@ void free_irqs(void) static void close_one_chan(struct chan *chan, int delay_free_irq) { + unsigned long flags; + if(!chan->opened) return; if(delay_free_irq){ - spin_lock_irq(&irqs_to_free_lock); + spin_lock_irqsave(&irqs_to_free_lock, flags); list_add(&chan->free_list, &irqs_to_free); - spin_unlock_irq(&irqs_to_free_lock); + spin_unlock_irqrestore(&irqs_to_free_lock, flags); } else { if(chan->input) -- 2.39.5