Re: [PATCH/RFC] PCI prepare/activate instead of enable to avoid IRQstorm and rogue DMA access

[Jeff Garzik]

Russell King wrote:
> pci_enable_device() doesn't deal with this; in most PCI setups I've
> seen, there is no control at PCI level over whether a device generates
> an interrupt on the bus.  Certainly the memory and io command enables

PCI grew an interrupt enable while you weren't looking: 
PCI_COMMAND_INTX_DISABLE

No idea about ARM, but almost all PCI devices made in the past few years 
support that bit.

Unless you are using a PCI Express device (maybe PCI-X too?), though, 
you cannot count on the bit's presence.  It was added in PCI 2.3 I 
think.  Older PCI devices certainly do not have this standardized bit.

	Jeff


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