On 5/5/06, Greg KH <[email protected]> wrote: > Who cares who "enabled" the device. Remember, the majority of PCI > devices in the system are not video ones. Lots of other types of > devices want this ability to enable PCI devices from userspace. I've > been talking with some people about how to properly write PCI drivers in > userspace, and this attribute is a needed part of it.
The problem is not who 'enabled' the device. The problem is who owns the state that has been loaded into the device. Without a mechanism like open there is no way to serialize the programs trying to set state into the device. fbdev and X have this fight currently. On every VT swap they each reload their state into the video hardware. There is no coordination so both systems have to assume worst case and rebuild everything. This is not a good environment to program in. Every time one of the systems starts using some new feature of hardware (like acceleration functions) new state recovery code needs to be written. -- Jon Smirl [email protected] - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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