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Subject: Re: [BK FBDEV] A few more updates.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: James Simmons <jsimmons@infradead.org>
Cc: Linus Torvalds <torvalds@transmeta.com>,
       Linux Fbdev development list 
	<linux-fbdev-devel@lists.sourceforge.net>,
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On Tue, 2003-03-25 at 19:28, Benjamin Herrenschmidt wrote:

> You "fixed" it by using GFP_ATOMIC but didn't test the result of
> kmalloc. That is very bad. GFP_ATOMIC can fail (return NULL), thus
> you will crash the kernel under high memory pressure.
> 
> I think the proper fix is, as you asked me, using a workqueue,
> that way, you can both use GFP_KERNEL allocations, and avoid
> the spinlock you added to fbmem.c, thus letting the fb_sync()
> ops on fbdev's be able to block.

Well, actually, creating a workqueue would be overhead since
it involves one kernel thread per CPU. After more thinking &
discussion, I beleive you shall rather use keventd existing
workqueue (schedule_work() will do that)

Ben.

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