| ELANPAR(4) | Device Drivers Manual (i386) | ELANPAR(4) |
elanpar — AMD Elan
SC520 Programmable Address Regions
elansc* at mainbus? bus ?
elanpar* at elansc?
The elanpar driver supports the
write-protect feature of the AMD Elan SC520 microcontroller's integrated
Programmable Address Regions. Currently, elanpar
protects the kernel text from being overwritten by the CPU or errant
DMA.
A Programmable Address Region stopped either the CPU, the general-purpose bus (gp), or a PCI bus master from writing to the indicated window of write-protected memory.
elanpar has not write-protected
%u bytes of the kernel
text.
The elanpar device first appeared in
NetBSD 5.0.
The elanpar driver was written by
David Young
<dyoung@NetBSD.org>.
elanpar leaves as many as 65535 bytes
unprotected at the beginning and end of kernel text. Also,
elanpar is not compatible with setting breakpoints
using ddb(4). Disable
elanpar using drvctl
-d elanpar0 before setting a
breakpoint with ddb(4).
| February 17, 2017 | NetBSD 11.0 |