Messages in this thread | | | Date | Fri, 30 Jul 2004 20:04:56 +0100 | From | Matthew Wilcox <> | Subject | Re: Exposing ROM's though sysfs |
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On Fri, Jul 30, 2004 at 11:59:21AM -0700, Jon Smirl wrote: > Alan Cox knows more about this, but I believe there is only one PCI > card in existence that does this.
Strange; he was the one who pointed out this requirement to me in the first place and he hinted that many devices did this.
> For the one or two cards that do this, the device drivers could flag > this to the PCI subsystem. In the flagged case the sysfs read code > could shut off interrupts, enable the ROM, copy it, and then reenable > interrupts.
Shutting off interrupts isn't nearly enough. Any other CPU could access the device, or indeed any device capable of DMA could potentially cause trouble.
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