diff options
| author | dwmalone <dwmalone@FreeBSD.org> | 2002-09-15 15:07:55 +0000 |
|---|---|---|
| committer | dwmalone <dwmalone@FreeBSD.org> | 2002-09-15 15:07:55 +0000 |
| commit | 6acc49e3bd177eb1e4787e9173c8443ceda1c25e (patch) | |
| tree | 12e1e1bf10ab9f5cfe0d9b564ef93fbde0e43737 /usr.sbin | |
| parent | 7819f421f3fd1e80387d5d7a0a52e8018b6f5edd (diff) | |
| download | FreeBSD-src-6acc49e3bd177eb1e4787e9173c8443ceda1c25e.zip FreeBSD-src-6acc49e3bd177eb1e4787e9173c8443ceda1c25e.tar.gz | |
Some BIOSs are using MTRR values that are only documented under NDA
to control the mapping of things like the ACPI and APM into memory.
The problem is that starting X changes these values, so if something
was using the bits of BIOS mapped into memory (say ACPI or APM),
then next time they access this memory the machine would hang.
This patch refuse to change MTRR values it doesn't understand,
unless a new "force" option is given. This means X doesn't change
them by accident but someone can override that if they really want
to.
PR: 28418
Tested by: Christopher Masto <chris@netmonger.net>,
David Bushong <david@bushong.net>,
Santos <casd@myrealbox.com>
MFC after: 1 week
Diffstat (limited to 'usr.sbin')
| -rw-r--r-- | usr.sbin/memcontrol/memcontrol.8 | 3 | ||||
| -rw-r--r-- | usr.sbin/memcontrol/memcontrol.c | 1 |
2 files changed, 3 insertions, 1 deletions
diff --git a/usr.sbin/memcontrol/memcontrol.8 b/usr.sbin/memcontrol/memcontrol.8 index 989eb16..f9d24a8 100644 --- a/usr.sbin/memcontrol/memcontrol.8 +++ b/usr.sbin/memcontrol/memcontrol.8 @@ -83,7 +83,8 @@ Length of memory range in bytes, power of 2 .It Fl o Ar owner Text identifier for this setting (7 char max) .It Ar attribute -Attributes applied to this range; one of +Attributes applied to this range; combinations of +.Ar force , .Ar uncacheable , .Ar write-combine , .Ar write-through , diff --git a/usr.sbin/memcontrol/memcontrol.c b/usr.sbin/memcontrol/memcontrol.c index 2554723..9eb8719 100644 --- a/usr.sbin/memcontrol/memcontrol.c +++ b/usr.sbin/memcontrol/memcontrol.c @@ -50,6 +50,7 @@ struct {"write-through", MDF_WRITETHROUGH, MDF_SETTABLE}, {"write-back", MDF_WRITEBACK, MDF_SETTABLE}, {"write-protect", MDF_WRITEPROTECT, MDF_SETTABLE}, + {"force", MDF_FORCE, MDF_SETTABLE}, {"unknown", MDF_UNKNOWN, 0}, {"fixed-base", MDF_FIXBASE, 0}, {"fixed-length", MDF_FIXLEN, 0}, |
