linux-sg2042/drivers/lguest
Rusty Russell c413fecc76 lguest: Fix guest crash when CONFIG_X86_USE_3DNOW=y
One of the very first things lguest_init() does is a memcpy.  On
Athlon/Duron/K7 or CyrixIII/VIA-C3 or Geode GX/LX, this tries to use
MMX.

memcpy -> _mmx_memcpy -> kernel_fpu_begin -> clts -> paravirt_ops.clts

But we haven't set paravirt_ops.clts yet, so we do the native version
and crash.  The simplest solution is to use __memcpy.

Thanks to Michael Rasenberger for the bug report.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-12 12:19:46 -07:00
..
Kconfig lguest should depend on CONFIG_FUTEX 2007-08-23 21:23:33 -07:00
Makefile lguest: documentation I: Preparation 2007-07-26 11:35:16 -07:00
README lguest: documentation I: Preparation 2007-07-26 11:35:16 -07:00
core.c lguest: Fix Malicious Guest GDT Host Crash 2007-08-09 08:14:56 -07:00
hypercalls.c Provide timespec to guests rather than jiffies clock. 2007-07-28 19:54:33 -07:00
interrupts_and_traps.c Fix lguest page-pinning logic ("lguest: bad stack page 0xc057a000") 2007-08-30 09:58:22 -07:00
io.c lguest: documentation VII: FIXMEs 2007-07-26 11:35:17 -07:00
lg.h Provide timespec to guests rather than jiffies clock. 2007-07-28 19:54:33 -07:00
lguest.c lguest: Fix guest crash when CONFIG_X86_USE_3DNOW=y 2007-09-12 12:19:46 -07:00
lguest_asm.S lguest: documentation VII: FIXMEs 2007-07-26 11:35:17 -07:00
lguest_bus.c lguest files should explicitly include asm/paravirt.h 2007-08-11 15:47:42 -07:00
lguest_user.c lguest: documentation IV: Launcher 2007-07-26 11:35:17 -07:00
page_tables.c lguest: documentation VII: FIXMEs 2007-07-26 11:35:17 -07:00
segments.c lguest: Fix Malicious Guest GDT Host Crash 2007-08-09 08:14:56 -07:00
switcher.S lguest: Fix Malicious Guest GDT Host Crash 2007-08-09 08:14:56 -07:00

README

Welcome, friend reader, to lguest.

Lguest is an adventure, with you, the reader, as Hero.  I can't think of many
5000-line projects which offer both such capability and glimpses of future
potential; it is an exciting time to be delving into the source!

But be warned; this is an arduous journey of several hours or more!  And as we
know, all true Heroes are driven by a Noble Goal.  Thus I offer a Beer (or
equivalent) to anyone I meet who has completed this documentation.

So get comfortable and keep your wits about you (both quick and humorous).
Along your way to the Noble Goal, you will also gain masterly insight into
lguest, and hypervisors and x86 virtualization in general.

Our Quest is in seven parts: (best read with C highlighting turned on)

I) Preparation
	- In which our potential hero is flown quickly over the landscape for a
	  taste of its scope.  Suitable for the armchair coders and other such
	  persons of faint constitution.

II) Guest
	- Where we encounter the first tantalising wisps of code, and come to
	  understand the details of the life of a Guest kernel.

III) Drivers
	- Whereby the Guest finds its voice and become useful, and our
	  understanding of the Guest is completed.

IV) Launcher
	- Where we trace back to the creation of the Guest, and thus begin our
	  understanding of the Host.

V) Host
	- Where we master the Host code, through a long and tortuous journey.
	  Indeed, it is here that our hero is tested in the Bit of Despair.

VI) Switcher
	- Where our understanding of the intertwined nature of Guests and Hosts
	  is completed.

VII) Mastery
	- Where our fully fledged hero grapples with the Great Question:
	  "What next?"

make Preparation!
Rusty Russell.