[Qemu-devel] kqemu descriptor table cache patch

[Henning Schild]

Hello,

i am currently porting kqemu to l4linux
(http://os.inf.tu-dresden.de/L4/LinuxOnL4/).
During my work i found that NetBSD does not map its GDT completely
which is the reason why it cant be used on kqemu. The GDT limit is
0xffff on NetBSD but only the first page of the GDT is mapped. Walking
the pagetable for the 2nd page fails.
Maybe there are other OSs out there that do the same thing ...

Kqemu returns pagefaults to the guest OS when LDT/GDT are not mapped
according to the given limits. I wrote a patch that keeps kqemu from
faulting when it updates its dt cache, instead all pages that are not
mapped will be skipped.

ftp://ftp.netbsd.org/pub/NetBSD/iso/livecd/netbsd-live-2007.iso
wont work with kqemu-1.3.0pre11, after applying the patch it will.

tested on a Linux host

regards,
Henning Schild

kqemu-1.3.0pre11_dont_fault_dt.patch
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