Messages in this thread | | | Subject | Re: [PATCH 1/3] PM: Introduce new top level suspend and hibernation callbacks (rev. 8) | From | Benjamin Herrenschmidt <> | Date | Mon, 14 Apr 2008 07:05:11 +1000 |
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On Sun, 2008-04-13 at 15:33 +0200, Rafael J. Wysocki wrote: > + * The PM core executes @prepare() for all devices before starting to > + * execute suspend callbacks for any of them, so drivers may assume all of > + * the other devices to be present and functional while @prepare() is being > + * executed. In particular, it is safe to make GFP_KERNEL memory > + * allocations from within @prepare(). However, drivers may NOT assume > + * anything about the availability of the user space at that time and it > + * is not correct to request firmware from within @prepare() (it's too > + * late to do that). [To work around this limitation, drivers may > + * register suspend and hibernation notifiers that are executed before the > + * freezing of tasks.]
Can you tell me why you kept that limitation with user space ?
I don't see the point... On the contrary, prepare() is the pefect place to implement handshaking with userspace for drivers that need to do so, such as the DRM.
Ben.
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