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The ExecShield patches

Posted Jul 20, 2005 2:54 UTC (Wed) by ch (subscriber, #4097)
Parent article: Kernel Summit 2005: The ExecShield patches

> About the only legitimate user is the X server, which uses /dev/mem
> for access to the frame buffer.

There are other user-space "device drivers" that use /dev/mem to get to memory mapped I/O devices, GPIO in particular.

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Posted Jul 25, 2005 18:31 UTC (Mon) by jsbarnes (guest, #4096) [Link]

Even X isn't a legitimate user--it can use the sysfs or /proc/bus/pci APIs
for accessing device memory (we're working on it for a future X.Org
release). Likewise, user level device drivers should use these
interfaces, /dev/mem will only get you into trouble (e.g. it's not very
portable or flexible).

The ExecShield patches

Posted Jul 31, 2005 2:13 UTC (Sun) by ch (subscriber, #4097) [Link]

It is just a set of conventions. If conventions against sysfs or /proc/bus/pci make more sense, that's fine. But sometimes the differences are just gratuitous. Maybe not here, but that's what to watch out for.