Hi. On Thu, 2005-03-17 at 15:11, Alan Stern wrote: > On Wed, 16 Mar 2005, David Brownell wrote: > > > > Wether the system IRQs must be masked or not is one thing that is > > > platform specific during suspend. Wether devices must stop their IRQ > > > emission, well... > > > > What's a "system IRQ" as opposed to any other kind? Drivers don't > > generally know or care how their IRQs are routed, they just care > > that they get a callback. > > Given that on some platforms it's necessary to leave some IRQs enabled for > remote wakeup to work, the definitions of FREEZE and SUSPEND need to be > changed. A quiesced device does not perform DMA and does not generate > interrupt requests _except_ that it may issue wakeup requests (which may > be IRQs) if it is enabled for remote wakeup. I don't think the definition of FREEZE needs to be changed because - unless I misunderstand - it is only used when swsusp and Suspend2 are doing their atomic copies. Pavel, is this right? > I don't think this will cause any problems for Suspend To Disk. If a > wakeup IRQ arrives before the system is asleep and is fielded by an > interrupt handler, the handler will try to start a resume. But resume > needs a process context to operate, and all processes will be frozen -- so > nothing will happen. Does the handler try to start a usermode helper program? Regards, Nigel -- Nigel Cunningham Software Engineer, Canberra, Australia http://www.cyclades.com Bus: +61 (2) 6291 9554; Hme: +61 (2) 6292 8028; Mob: +61 (417) 100 574 Maintainer of Suspend2 Kernel Patches http://suspend2.net
