diff options
Diffstat (limited to 'drivers/lguest/segments.c')
| -rw-r--r-- | drivers/lguest/segments.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/lguest/segments.c b/drivers/lguest/segments.c index 1b2cfe8..c4fc729 100644 --- a/drivers/lguest/segments.c +++ b/drivers/lguest/segments.c @@ -1,3 +1,14 @@ +/*P:600 The x86 architecture has segments, which involve a table of descriptors + * which can be used to do funky things with virtual address interpretation. + * We originally used to use segments so the Guest couldn't alter the + * Guest<->Host Switcher, and then we had to trim Guest segments, and restore + * for userspace per-thread segments, but trim again for on userspace->kernel + * transitions... This nightmarish creation was contained within this file, + * where we knew not to tread without heavy armament and a change of underwear. + * + * In these modern times, the segment handling code consists of simple sanity + * checks, and the worst you'll experience reading this code is butterfly-rash + * from frolicking through its parklike serenity. :*/ #include "lg.h" static int desc_ok(const struct desc_struct *gdt) |
