Commit graph

18 commits

Author SHA1 Message Date
Rusty Russell
05ff09706b Make lguest compile with CONFIG_BLOCK=n and CONFIG_NET=n
Gabriel C reports lguest doesn't compile with CONFIG_BLOCK=n.  Fix this
by introducing a config var for the block device, which depends on
LGUEST && BLOCK.  Do the same for the net driver, rather then depending
gratuitously on CONFIG_NET.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Gabriel C <nix.or.die@googlemail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-29 17:37:45 -07:00
Rusty Russell
6c8dca5d53 Provide timespec to guests rather than jiffies clock.
A non-periodic clock_event_device and the "jiffies" clock don't mix well:
tick_handle_periodic() can go into an infinite loop.

Currently lguest guests use the jiffies clock when the TSC is
unusable.  Instead, make the Host write the current time into the lguest
page on every interrupt.  This doesn't cost much but is more precise
and at least as accurate as the jiffies clock.  It also gets rid of
the GET_WALLCLOCK hypercall.

Also, delay setting sched_clock until our clock is set up, otherwise
the early printk timestamps can go backwards (not harmful, just ugly).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-28 19:54:33 -07:00
Rusty Russell
a8a11f0697 Fix lguest bzImage loading with CONFIG_RELOCATABLE=y
Jason Yeh sent his crashing .config: bzImages made with
CONFIG_RELOCATABLE=y put the relocs where the BSS is expected, and we
crash with unusual results such as:

	lguest: unhandled trap 14 at 0xc0122ae1 (0xa9)

Relying on BSS being zero was merely laziness on my part, and
unfortunately, lguest doesn't go through the normal startup path (which
does this in asm).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-28 19:53:36 -07:00
Rusty Russell
f56a384e98 lguest: documentation VII: FIXMEs
Documentation: The FIXMEs

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:17 -07:00
Rusty Russell
f8f0fdcd40 lguest: documentation VI: Switcher
Documentation: The Switcher

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:17 -07:00
Rusty Russell
bff672e630 lguest: documentation V: Host
Documentation: The Host

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:17 -07:00
Rusty Russell
dde797899a lguest: documentation IV: Launcher
Documentation: The Launcher

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:17 -07:00
Rusty Russell
e2c9784325 lguest: documentation III: Drivers
Documentation: The Drivers

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:17 -07:00
Rusty Russell
b2b47c214f lguest: documentation II: Guest
Documentation: The Guest

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:17 -07:00
Rusty Russell
f938d2c892 lguest: documentation I: Preparation
The netfilter code had very good documentation: the Netfilter Hacking HOWTO.
Noone ever read it.

So this time I'm trying something different, using a bit of Knuthiness.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26 11:35:16 -07:00
Thomas Gleixner
18de5bc4c1 clockevents: fix resume logic
We need to make sure, that the clockevent devices are resumed, before
the tick is resumed. The current resume logic does not guarantee this.

Add CLOCK_EVT_MODE_RESUME and call the set mode functions of the clock
event devices before resuming the tick / oneshot functionality.

Fixup the existing users.

Thanks to Nigel Cunningham for tracking down a long standing thinko,
which affected the jinxed VAIO.

[akpm@linux-foundation.org: xen build fix]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-21 17:49:15 -07:00
Rusty Russell
9d1ca6f13c lguest: override sched_clock
Guests currently use the default scheduler clock: this means they
always use jiffies even if TSC is actually available.  It doesn't make
any noticeable difference here, but it's a better thing to do.

Also remove commented-out asm/sched-clock.h from -mm tree.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-20 09:05:16 -07:00
Rusty Russell
876be9d89e lguest: trivial: We now have asm/processor-flags.h, so use it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-20 09:05:16 -07:00
Rusty Russell
e5faff45b3 lguest: fix sense if IF flag on interrupt injection
The sense of the IF bit is backwards in the host interrupt handling.

This means we always save "IF=1" on the stack when injecting an
interrupt.  It turns out this is almost always correct (unless the
guest is taking a page fault in an interrupt due to an unpopulated
vmalloc mapping), so went unnoticed.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-20 09:05:16 -07:00
Al Viro
6d14bfe77b Fix lguest misannotation
It's void __user *, not void * __user...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-20 08:24:49 -07:00
Rusty Russell
709e89266b lguest: the Makefile and Kconfig
This is the Kconfig and Makefile to allow lguest to actually be
compiled.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:52 -07:00
Rusty Russell
d7e28ffe6c lguest: the host code
This is the code for the "lg.ko" module, which allows lguest guests to
be launched.

[akpm@linux-foundation.org: update for futex-new-private-futexes]
[akpm@linux-foundation.org: build fix]
[jmorris@namei.org: lguest: use hrtimers]
[akpm@linux-foundation.org: x86_64 build fix]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:52 -07:00
Rusty Russell
07ad157f6e lguest: the guest code
lguest is a simple hypervisor for Linux on Linux.  Unlike kvm it doesn't need
VT/SVM hardware.  Unlike Xen it's simply "modprobe and go".  Unlike both, it's
5000 lines and self-contained.

Performance is ok, but not great (-30% on kernel compile).  But given its
hackability, I expect this to improve, along with the paravirt_ops code which
it supplies a complete example for.  There's also a 64-bit version being
worked on and other craziness.

But most of all, lguest is awesome fun!  Too much of the kernel is a big ball
of hair.  lguest is simple enough to dive into and hack, plus has some warts
which scream "fork me!".

This patch:

This is the code and headers required to make an i386 kernel an lguest guest.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:52 -07:00