Commit Graph

175 Commits

Author SHA1 Message Date
Rusty Russell
1dc3e3bcbf lguest: update commentry
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-08-26 00:19:28 +10:00
Rusty Russell
71a3f4edc1 lguest: use get_user_pages_fast() instead of get_user_pages()
Using a simple page table thrashing program I measure a slight
improvement.  The program creates five processes.  Each touches 1000
pages then schedules the next process.  We repeat this 1000 times.  As
lguest only caches 4 cr3 values, this rebuilds a lot of shadow page
tables requiring virt->phys mappings.

	Before: 5.93 seconds
	After: 5.40 seconds

(Counts of slow vs fastpath in this usage are 6092 and 2852462 respectively.)

And more importantly for lguest, the code is simpler.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-08-12 17:52:53 +10:00
Andrew Morton
cf485e566b lguest: use cpu capability accessors
To support my little make-x86-bitops-use-proper-typechecking projectlet.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29 09:58:34 +10:00
Johannes Weiner
0a707210aa lguest: fix switcher_page leak on unload
map_switcher allocates the array, unmap_switcher has to free it
accordingly.

Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29 09:58:32 +10:00
Rusty Russell
0c12091d82 lguest: Guest int3 fix
Ron Minnich noticed that guest userspace gets a GPF when it tries to int3:
we need to copy the privilege level from the guest-supplied IDT to the real
IDT.  int3 is the only common case where guest userspace expects to invoke
an interrupt, so that's the symptom of failing to do this.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29 09:58:31 +10:00
Rusty Russell
e34f872567 virtio: Add transport feature handling stub for virtio_ring.
To prepare for virtio_ring transport feature bits, hook in a call in
all the users to manipulate them.  This currently just clears all the
bits, since it doesn't understand any features.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:14 +10:00
Rusty Russell
c624896e48 virtio: Rename set_features to finalize_features
Rather than explicitly handing the features to the lower-level, we just
hand the virtio_device and have it set the features.  This make it clear
that it has the chance to manipulate the features of the device at this
point (and that all feature negotiation is already done).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25 12:06:12 +10:00
Ingo Molnar
1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Ingo Molnar
15e551d25e x86, VisWS: turn into generic arch, eliminate Kconfig specials
remove leftover traces of various VISWS related Kconfig specials.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-10 18:55:47 +02:00
Jens Axboe
15c8b6c1aa on_each_cpu(): kill unused 'retry' parameter
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:38 +02:00
Ingo Molnar
d02859ecb3 Merge commit 'v2.6.26-rc8' into x86/xen
Conflicts:

	arch/x86/xen/enlighten.c
	arch/x86/xen/mmu.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-25 12:16:51 +02:00
Suresh Siddha
54481cf88b x86: fix NULL pointer deref in __switch_to
I am able to reproduce the oops reported by Simon in __switch_to() with
lguest.

My debug showed that there is at least one lguest specific
issue (which should be present in 2.6.25 and before aswell) and it got
exposed with a kernel oops with the recent fpu dynamic allocation patches.

In addition to the previous possible scenario (with fpu_counter), in the
presence of lguest, it is possible that the cpu's TS bit it still set and the
lguest launcher task's thread_info has TS_USEDFPU still set.

This is because of the way the lguest launcher handling the guest's TS bit.
(look at lguest_set_ts() in lguest_arch_run_guest()). This can result
in a DNA fault while doing unlazy_fpu() in __switch_to(). This will
end up causing a DNA fault in the context of new process thats
getting context switched in (as opossed to handling DNA fault in the context
of lguest launcher/helper process).

This is wrong in both pre and post 2.6.25 kernels. In the recent
2.6.26-rc series, this is showing up as NULL pointer dereferences or
sleeping function called from atomic context(__switch_to()), as
we free and dynamically allocate the FPU context for the newly
created threads. Older kernels might show some FPU corruption for processes
running inside of lguest.

With the appended patch, my test system is running for more than 50 mins
now. So atleast some of your oops (hopefully all!) should get fixed.
Please give it a try. I will spend more time with this fix tomorrow.

Reported-by: Simon Holm Thøgersen <odie@cs.aau.dk>
Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20 13:26:18 +02:00
Ingo Molnar
688d22e23a Merge branch 'linus' into x86/xen 2008-06-16 11:21:27 +02:00
Rusty Russell
b769f57908 virtio: set device index in common code.
Anthony Liguori points out that three different transports use the virtio code,
but each one keeps its own counter to set the virtio_device's index field.  In
theory (though not in current practice) this means that names could be
duplicated, and that risk grows as more transports are created.

So we move the selection of the unique virtio_device.index into the common code
in virtio.c, which has the side-benefit of removing duplicate code.

The only complexity is that lguest and S/390 use the index to uniquely identify
the device in case of catastrophic failure before register_virtio_device() is
called: now we use the offset within the descriptor page as a unique identifier
for the printks.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Lalancette <clalance@redhat.com>
Cc: Anthony Liguori <anthony@codemonkey.ws>
2008-05-30 15:09:42 +10:00
Rusty Russell
e27810f113 lguest: use ioremap_cache, not ioremap
Thanks to Jon Corbet & LWN.  Only took me a day to join the dots.

Host->Guest netcat before (with unnecessily large receive buffers):
1073741824 bytes (1.1 GB) copied, 24.7528 seconds, 43.4 MB/s

After:
1073741824 bytes (1.1 GB) copied, 17.6369 seconds, 60.9 MB/s

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-30 15:09:41 +10:00
Jeremy Fitzhardinge
a15af1c9ea x86/paravirt: add pte_flags to just get pte flags
Add pte_flags() to extract the flags from a pte.  This is a special
case of pte_val() which is only guaranteed to return the pte's flags
correctly; the page number may be corrupted or missing.

The intent is to allow paravirt implementations to return pte flags
without having to do any translation of the page number (most notably,
Xen).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:36 +02:00
Rusty Russell
a007a751d9 lguest: make Launcher see device status updates
This brings us closer to Real Life, where we'd examine the device
features once it's set the DRIVER_OK status bit.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:54 +10:00
Rusty Russell
9f3f746741 lguest: remove bogus NULL cpu check
If lg isn't NULL, and cpu_id is sane, &lg->cpus[cpu_id] can't be NULL.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:52 +10:00
Rusty Russell
24adf12722 lguest: avoid using NR_CPUS as a bounds check.
NR_CPUS (being a host number) is an arbitrary limit for the Guest.
Using the array size directly (which currently happes to be NR_CPUS)
is more futureproof.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:51 +10:00
Rusty Russell
c45a6816c1 virtio: explicit advertisement of driver features
A recent proposed feature addition to the virtio block driver revealed
some flaws in the API: in particular, we assume that feature
negotiation is complete once a driver's probe function returns.

There is nothing in the API to require this, however, and even I
didn't notice when it was violated.

So instead, we require the driver to specify what features it supports
in a table, we can then move the feature negotiation into the virtio
core.  The intersection of device and driver features are presented in
a new 'features' bitmap in the struct virtio_device.

Note that this highlights the difference between Linux unsigned-long
bitmaps where each unsigned long is in native endian, and a
straight-forward little-endian array of bytes.

Drivers can still remove feature bits in their probe routine if they
really have to.

API changes:
- dev->config->feature() no longer gets and acks a feature.
- drivers should advertise their features in the 'feature_table' field
- use virtio_has_feature() for extra sanity when checking feature bits

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-02 21:50:50 +10:00
Matthew Wilcox
d3135846f6 drivers: Remove unnecessary inclusions of asm/semaphore.h
None of these files use any of the functionality promised by
asm/semaphore.h.  It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-18 22:16:32 -04:00
Al Viro
74dbf719ed misc __user misannotations (pointless casts to long)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-30 14:20:23 -07:00
Rusty Russell
a6bd8e1303 lguest: comment documentation update.
Took some cycles to re-read the Lguest Journey end-to-end, fix some
rot and tighten some phrases.

Only comments change.  No new jokes, but a couple of recycled old jokes.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-28 11:05:54 +11:00
Tim Ansell
b488f22d70 lguest: Add puppies which where previously missing.
lguest doesn't have features, it has puppies!

Signed-off-by: Timothy R Ansell <mithro@mithis.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-28 11:05:52 +11:00
Rusty Russell
4357bd9453 lguest: Revert 1ce70c4fac, fix real problem.
Ahmed managed to crash the Host in release_pgd(), which cannot be a Guest
bug, and indeed it wasn't.

The bug was that handing a 0 as the address of the toplevel page table
being manipulated can cause the lookup code in find_pgdir() to return
an uninitialized cache entry (we shadow up to 4 top level page tables
for each Guest).

Commit 37cc8d7f96 introduced this
behaviour in the Guest, uncovering the bug.

The patch which he submitted (which removed the /4 from the index
calculation) simply ensured that these high-indexed entries hit the
early exit path of guest_set_pmd().  But you get lots of segfaults in
guest userspace as the PMDs aren't being updated.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-11 09:35:58 +11:00
Rusty Russell
f14ae652ba lguest: fix __get_vm_area usage.
Robert Bragg's 5dc3318528 tightened
(ie. fixed) the checking in __get_vm_area, and it broke lguest.

lguest should pass the exact "end" it wants, not some random constant
(it was possible previously that it would actually get an address
different from SWITCHER_ADDR).

Also, Fabio Checconi pointed out that we should make sure we're not
hitting the fixmap area.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Robert Bragg <robert@sixbynine.org>
2008-03-11 09:35:56 +11:00
Eugene Teo
f73d1e6ca6 lguest: make sure cpu is initialized before accessing it
If req is LHREQ_INITIALIZE, and the guest has been initialized before
(unlikely), it will attempt to access cpu->tsk even though cpu is not yet
initialized.

Signed-off-by: Eugene Teo <eugeneteo@kernel.sg>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-11 09:35:56 +11:00
Ahmed S. Darwish
31f4b46ec6 lguest: accept guest _PAGE_PWT page table entries
Beginning from commit 4138cc3418, ioremap_nocache() sets the _PAGE_PWT
flag.

Lguest doesn't accept a guest pte with a _PWT flag and reports a "bad
page table entry" in that case.

Accept guest _PAGE_PWT page table entries.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-09 23:24:09 +01:00
Alexey Dobriyan
25478445c4 Fix container_of() usage
Using "attr" twice is not OK, because it effectively prohibits such
container_of() on variables not named "attr".

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-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>
2008-02-08 09:22:32 -08:00
Rusty Russell
6e5aa7efb2 virtio: reset function
A reset function solves three problems:

1) It allows us to renegotiate features, eg. if we want to upgrade a
   guest driver without rebooting the guest.

2) It gives us a clean way of shutting down virtqueues: after a reset,
   we know that the buffers won't be used by the host, and

3) It helps the guest recover from messed-up drivers.

So we remove the ->shutdown hook, and the only way we now remove
feature bits is via reset.

We leave it to the driver to do the reset before it deletes queues:
the balloon driver, for example, needs to chat to the host in its
remove function.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:50:03 +11:00
Rusty Russell
18445c4d50 virtio: explicit enable_cb/disable_cb rather than callback return.
It seems that virtio_net wants to disable callbacks (interrupts) before
calling netif_rx_schedule(), so we can't use the return value to do so.

Rename "restart" to "cb_enable" and introduce "cb_disable" hook: callback
now returns void, rather than a boolean.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:49:58 +11:00
Rusty Russell
a586d4f601 virtio: simplify config mechanism.
Previously we used a type/len pair within the config space, but this
seems overkill.  We now simply define a structure which represents the
layout in the config space: the config space can now only be extended
at the end.

The main driver-visible changes:
1) We indicate what fields are present with an explicit feature bit.
2) Virtqueues are explicitly numbered, and not in the config space.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-02-04 23:49:57 +11:00
Rusty Russell
e95035c61a lguest: fix mis-merge against hpa's TSS renaming
drivers/lguest/x86/core.c: In function ‘copy_in_guest_info’:
drivers/lguest/x86/core.c:97: error: ‘struct x86_hw_tss’ has no member named ‘esp1’

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-31 19:59:44 +11:00
Linus Torvalds
d145c7253c Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: (27 commits)
  lguest: use __PAGE_KERNEL instead of _PAGE_KERNEL
  lguest: Use explicit includes rateher than indirect
  lguest: get rid of lg variable assignments
  lguest: change gpte_addr header
  lguest: move changed bitmap to lg_cpu
  lguest: move last_pages to lg_cpu
  lguest: change last_guest to last_cpu
  lguest: change spte_addr header
  lguest: per-vcpu lguest pgdir management
  lguest: make pending notifications per-vcpu
  lguest: makes special fields be per-vcpu
  lguest: per-vcpu lguest task management
  lguest: replace lguest_arch with lg_cpu_arch.
  lguest: make registers per-vcpu
  lguest: make emulate_insn receive a vcpu struct.
  lguest: map_switcher_in_guest() per-vcpu
  lguest: per-vcpu interrupt processing.
  lguest: per-vcpu lguest timers
  lguest: make hypercalls use the vcpu struct
  lguest: make write() operation smp aware
  ...

Manual conflict resolved (maybe even correctly, who knows) in
drivers/lguest/x86/core.c
2008-01-31 09:35:32 +11:00
H. Peter Anvin
faca62273b x86: use generic register name in the thread and tss structures
This changes size-specific register names (eip/rip, esp/rsp, etc.) to
generic names in the thread and tss structures.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:02 +01:00
Glauber de Oliveira Costa
84f12e39c8 lguest: use __PAGE_KERNEL instead of _PAGE_KERNEL
x86_64 don't expose the intermediate representation with one underline,
_PAGE_KERNEL, just the double-underlined one.

Use it, to get a common ground between 32 and 64-bit

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:19 +11:00
Glauber de Oliveira Costa
ca94f2bdd1 lguest: Use explicit includes rateher than indirect
explicitly use ktime.h include
explicitly use hrtimer.h include
explicitly use sched.h include

This patch adds headers explicitly to lguest sources file,
to avoid depending on them being included somewhere else.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:19 +11:00
Glauber de Oliveira Costa
382ac6b3fb lguest: get rid of lg variable assignments
We can save some lines of code by getting rid of
*lg = cpu... lines of code spread everywhere by now.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:18 +11:00
Glauber de Oliveira Costa
934faab464 lguest: change gpte_addr header
gpte_addr() does not depend on any guest information. So we wipe out
the lg parameter from it completely.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:18 +11:00
Glauber de Oliveira Costa
ae3749dcd8 lguest: move changed bitmap to lg_cpu
events represented in the 'changed' bitmap are per-cpu, not per-guest.
move it to the lg_cpu structure

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:17 +11:00
Glauber de Oliveira Costa
f34f8c5fea lguest: move last_pages to lg_cpu
in our new model, pages are assigned to a virtual cpu, not to a guest.
We move it to the lg_cpu structure.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:16 +11:00
Glauber de Oliveira Costa
c40a9f4719 lguest: change last_guest to last_cpu
in our model, a guest does not run in a cpu anymore: a virtual cpu
does. So we change last_guest to last_cpu

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:15 +11:00
Glauber de Oliveira Costa
2092aa277b lguest: change spte_addr header
spte_addr does not depend on any guest information, so we
wipe out the lg parameter completely.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:15 +11:00
Glauber de Oliveira Costa
1713608f28 lguest: per-vcpu lguest pgdir management
this patch makes the pgdir management per-vcpu. The pgdirs pool
is still guest-wide (although it'll probably need to grow when we
are really executing more vcpus), but the pgdidx index is gone,
since it makes no sense anymore. Instead, we use a per-vcpu
index.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:14 +11:00
Glauber de Oliveira Costa
5e232f4f42 lguest: make pending notifications per-vcpu
this patch makes the pending_notify field, used to control
pending notifications, per-vcpu, instead of per-guest

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:13 +11:00
Glauber de Oliveira Costa
4665ac8e28 lguest: makes special fields be per-vcpu
lguest struct have room for some fields, namely, cr2, ts, esp1
and ss1, that are not really guest-wide, but rather, vcpu-wide.

This patch puts it in the vcpu struct

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:13 +11:00
Glauber de Oliveira Costa
66686c2ab0 lguest: per-vcpu lguest task management
lguest uses tasks to control its running behaviour (like sending
breaks, controlling halted state, etc). In a per-vcpu environment,
each vcpu will have its own underlying task. So this patch
makes the infrastructure for that possible

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:12 +11:00
Glauber de Oliveira Costa
fc708b3e40 lguest: replace lguest_arch with lg_cpu_arch.
The fields found in lguest_arch are not really per-guest,
but per-cpu (gdt, idt, etc). So this patch turns lguest_arch
into lg_cpu_arch.

It makes sense to have a per-guest per-arch struct, but this
can be addressed later, when the need arrives.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:11 +11:00
Glauber de Oliveira Costa
a53a35a8b4 lguest: make registers per-vcpu
This is the most obvious per-vcpu field: registers.

So this patch moves it from struct lguest to struct vcpu,
and patch the places in which they are used, accordingly

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:11 +11:00
Glauber de Oliveira Costa
a3863f68b0 lguest: make emulate_insn receive a vcpu struct.
emulate_insn() needs to know about current eip, which will be,
in the future, a per-vcpu thing. So in this patch, the function
prototype is modified to receive a vcpu struct

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:10 +11:00
Glauber de Oliveira Costa
0c78441cf4 lguest: map_switcher_in_guest() per-vcpu
The switcher needs to be mapped per-vcpu, because different vcpus
will potentially have different page tables (they don't have to,
because threads will share the same).

So our first step is the make the function receive a vcpu struct

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:09 +11:00
Glauber de Oliveira Costa
177e449dc5 lguest: per-vcpu interrupt processing.
This patch adapts interrupt processing for using the vcpu struct.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:09 +11:00
Glauber de Oliveira Costa
ad8d8f3bc6 lguest: per-vcpu lguest timers
Here, I introduce per-vcpu timers. With this, we can have
local expiries, needed for accounting time in smp guests

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:08 +11:00
Glauber de Oliveira Costa
73044f05a4 lguest: make hypercalls use the vcpu struct
this patch changes do_hcall() and do_async_hcall() interfaces (and obviously their
callers) to get a vcpu struct. Again, a vcpu services the hypercall, not the whole
guest

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:08 +11:00
Glauber de Oliveira Costa
7ea07a1500 lguest: make write() operation smp aware
This patch makes the write() file operation smp aware. Which means, receiving
the vcpu_id value through the offset parameter, and being well aware to which
vcpu we're talking to.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:07 +11:00
Glauber de Oliveira Costa
d0953d42c3 lguest: per-cpu run guest
This patch makes the run_guest() routine use the lg_cpu struct.
This is required since in a smp guest environment, there's no
more the notion of "running the guest", but rather, it is "running the vcpu"

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:06 +11:00
Glauber de Oliveira Costa
4dcc53da49 lguest: initialize vcpu
this patch initializes the first vcpu in the initialize() routing,
which is responsible for starting the process of putting the guest up.
right now, as much of the fields are still not per-vcpu, it does not
do much.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:06 +11:00
Glauber de Oliveira Costa
badb1e0402 lguest: introduce vcpu struct
this patch introduces a vcpu struct for lguest. In upcoming patches,
more and more fields will be moved from the lguest struct to the vcpu

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:04 +11:00
Balaji Rao
ec04b13f67 lguest: Reboot support
Reboot Implemented

(Prevent fd leak, fix style and fix documentation --RR)

Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:04 +11:00
Glauber de Oliveira Costa
5c55841d16 lguest: remove pv_info dependency
Currently, lguest module can't be compiled without the PARAVIRT flag being
on. This is a fake dependency, since the module itself shouldn't need any
paravirt override. Reason for that is the reference to pv_info structure
in initial loading tests.

This patch removes it in favour of a more generic error message.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-01-30 22:50:03 +11:00
Gautham R Shenoy
86ef5c9a8e cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus()
Replace all lock_cpu_hotplug/unlock_cpu_hotplug from the kernel and use
get_online_cpus and put_online_cpus instead as it highlights the
refcount semantics in these operations.

The new API guarantees protection against the cpu-hotplug operation, but
it doesn't guarantee serialized access to any of the local data
structures. Hence the changes needs to be reviewed.

In case of pseries_add_processor/pseries_remove_processor, use
cpu_maps_update_begin()/cpu_maps_update_done() as we're modifying the
cpu_present_map there.

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-25 21:08:02 +01:00
Rusty Russell
a7da60f415 Remove bogus duplicate CONFIG_LGUEST_GUEST entry.
It was moved to arch/x86/lguest/Kconfig, but I lost the deletion part in a
patch suffle.  My confused one-liner "fix" to turn it on is also reverted:
84f7466ee2

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-19 21:29:39 -08:00
Rusty Russell
84f7466ee2 Selecting LGUEST should turn on Guest support, as in 2.6.23.
There's currently no way to turn on Lguest guest support; the planned
Kconfig virtualization reorg didn't get into 2.6.25.

This was unnoticed because if you already had CONFIG_LGUEST_GUEST=y in
your config, it worked.  Too bad about new users...

Also, the Kconfig help was wrong now the virtio drivers are merged.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-18 14:05:48 -08:00
Rusty Russell
74b2553f1d virtio: fix module/device unloading
The virtio code never hooked through the ->remove callback.  Although
noone supports device removal at the moment, this code is already
needed for module unloading.

This of course also revealed bugs in virtio_blk, virtio_net and lguest
unloading paths.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-11-19 11:20:42 +11:00
Adrian Bunk
43054412db lguest_user.c: fix memory leak
This patch fixes a memory leak spotted by the Coverity checker.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
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>
2007-11-14 18:45:38 -08:00
Rusty Russell
42b36cc0ce virtio: Force use of power-of-two for descriptor ring sizes
The virtio descriptor rings of size N-1 were nicely set up to be
aligned to an N-byte boundary.  But as Anthony Liguori points out, the
free-running indices used by virtio require that the sizes be a power
of 2, otherwise we get problems on wrap (demonstrated with lguest).

So we replace the clever "2^n-1" scheme with a simple "align to page
boundary" scheme: this means that all virtio rings take at least two
pages, but it's safer than guessing cache alignment.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-11-12 13:59:40 +11:00
Rusty Russell
e1e72965ec lguest: documentation update
Went through the documentation doing typo and content fixes.  This
patch contains only comment and whitespace changes.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-25 15:02:50 +10:00
Rusty Russell
197bff630a lguest: remove unused "wake" element from struct lguest
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-25 14:10:30 +10:00
Rusty Russell
25c47bb353 lguest: use defines from x86 headers instead of magic numbers
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-25 14:09:53 +10:00
Rusty Russell
2d37f94a28 generalize lgread_u32/lgwrite_u32.
Jes complains that page table code still uses lgread_u32 even though
it now uses general kernel pte types.  The best thing to do is to
generalize lgread_u32 and lgwrite_u32.

This means we lose the efficiency of getuser().  We could potentially
regain it if we used __copy_from_user instead of copy_from_user, but
I'm not certain that our range check is equivalent to access_ok() on
all platforms.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Jes Sorensen <jes@sgi.com>
2007-10-23 15:49:56 +10:00
Rusty Russell
19f1537b7b Lguest support for Virtio
This makes lguest able to use the virtio devices.

We change the device descriptor page from a simple array to a variable
length "type, config_len, status, config data..." format, and
implement virtio_config_ops to read from that config data.

We use the virtio ring implementation for an efficient Guest <-> Host
virtqueue mechanism, and the new LHCALL_NOTIFY hypercall to kick the
host when it changes.

We also use LHCALL_NOTIFY on kernel addresses for very very early
console output.  We could have another hypercall, but this hack works
quite well.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:56 +10:00
Rusty Russell
15045275c3 Remove old lguest I/O infrrasructure.
This patch gets rid of the old lguest host I/O infrastructure and
replaces it with a single hypercall "LHCALL_NOTIFY" which takes an
address.

The main change is the removal of io.c: that mainly did inter-guest
I/O, which virtio doesn't yet support.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:55 +10:00
Rusty Russell
0ca49ca946 Remove old lguest bus and drivers.
This gets rid of the lguest bus, drivers and DMA mechanism, to make
way for a generic virtio mechanism.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:55 +10:00
Rusty Russell
47436aa4ad Boot with virtual == physical to get closer to native Linux.
1) This allows us to get alot closer to booting bzImages.

2) It means we don't have to know page_offset.

3) The Guest needs to modify the boot pagetables to create the
   PAGE_OFFSET mapping before jumping to C code.

4) guest_pa() walks the page tables rather than using page_offset.

5) We don't use page_offset to figure out whether to emulate: it was
   always kinda quesationable, and won't work for instructions done
   before remapping (bzImage unpacking in particular).

6) We still want the kernel address for tlb flushing: have the initial
   hypercall give us that, too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:54 +10:00
Rusty Russell
c18acd73ff Allow guest to specify syscall vector to use.
(Based on Ron Minnich's LGUEST_PLAN9_SYSCALL patch).

This patch allows Guests to specify what system call vector they want,
and we try to reserve it.  We only allow one non-Linux system call
vector, to try to avoid DoS on the Host.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:53 +10:00
Rusty Russell
ee3db0f2b6 Rename "cr3" to "gpgdir" to avoid x86-specific naming.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:53 +10:00
Matias Zabaljauregui
df29f43e65 Pagetables to use normal kernel types
This is my first step in the migration of page_tables.c to the kernel
types and functions/macros (2.6.23-rc3).  Seems to be working OK.

Signed-off-by: Matias Zabaljauregui <matias.zabaljauregui@cern.ch>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:53 +10:00
Jes Sorensen
d612cde060 Move register setup into i386_core.c
Move setup_regs() to lguest_arch_setup_regs() in i386_core.c given
that this is very architecture specific.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:52 +10:00
Jes Sorensen
511801dc31 Change example launcher to use unsigned long not u32
Apply Clue 2x4 to lguest userland<->kernel handling code and the
lguest launcher. Pointers are not to be passed in u32's!

Basic rule of thumb: Anything passing u32's back and forth should be
passing unsigned longs to be portable to 64 bit archs.

For those who forgotten already, I repeat: NO POINTERS IN u32!

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:52 +10:00
Jes Sorensen
b410e7b149 Make hypercalls arch-independent.
Clean up the hypercall code to make the code in hypercalls.c
architecture independent. First process the common hypercalls and
then call lguest_arch_do_hcall() if the call hasn't been handled.
Rename struct hcall_ring to hcall_args.

This patch requires the previous patch which reorganize the layout of
struct lguest_regs on i386 so they match the layout of struct
hcall_args.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:52 +10:00
Rusty Russell
cc6d4fbcef Introduce "hcall" pointer to indicate pending hypercall.
Currently we look at the "trapnum" to see if the Guest wants a
hypercall.  But once the hypercall is done we have to reset trapnum to
a bogus value, otherwise if we exit to userspace and return, we'd run
the same hypercall twice (that was a nasty bug to find!).

This has two main effects:

1) When Jes's patch changes the hypercall args to be a generic "struct
   hcall_args" we simply change the type of "lg->hcall".  It's set by
   arch code, so if it has to copy args or something it can do so, and
   point "hcall" into lg->arch somewhere.

2) Async hypercalls only get run when an actual hypercall is pending.
   This simplfies the code a little and is a more logical semantic.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:52 +10:00
Jes Sorensen
4614a3a3b6 Reorder guest saved regs to match hyperall order
Move eax next to ebx/ecx/edx in struct lguest_regs on i386, so they
will be located together and allow it to map directly to a struct
hcall_ring entry (which will be renamed struct hcall_args as in a
subsequent patch).

This is in preparation for making the code hcall code architecture
independent.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:51 +10:00
Jes Sorensen
625efab1cd Move i386 part of core.c to x86/core.c.
Separate i386 architecture specific from core.c and move it to
x86/core.c and add x86/lguest.h header file to match.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:51 +10:00
Rusty Russell
56adbe9ddc Make shadow IDT a complete IDT with 256 entries.
This simplifies the code a little, in preparation for allowing
alternate system call vectors in guests (Plan 9 uses 0x40).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:51 +10:00
Rusty Russell
48245cc070 Remove fixed limit on number of guests, and lguests array.
Back when we had all the Guest state in the switcher, we had a fixed
array of them.  This is no longer necessary.

If we switch the network code to using random_ether_addr (46 bits is
enough to avoid clashes), we can get rid of the concept of "guest id"
altogether.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:51 +10:00
Rusty Russell
3c6b5bfa3c Introduce guest mem offset, static link example launcher
In order to avoid problematic special linking of the Launcher, we give
the Host an offset: this means we can use any memory region in the
Launcher as Guest memory rather than insisting on mmap() at 0.

The result is quite pleasing: a number of casts are replaced with
simple additions.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:50 +10:00
Rusty Russell
1f4e1de4f2 Rename switcher.S to x86/switcher_32.S
lguest uses a "switcher" shim mapped high to bounce between host and
guest.  As lguest becomes less i386-centric, we separate this code
into a subdir.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:50 +10:00
Rusty Russell
34b8867a03 Move lguest guest support to arch/x86.
Lguest has two sides: host support (to launch guests) and guest
support (replacement boot path and paravirt_ops).  This moves the
guest side to arch/x86/lguest where it's closer to related code.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
2007-10-23 15:49:50 +10:00
Tony Breeds
05aa026a62 Clocksource is continuous regardless of the state of the host's TSC.
Currently lguest will spend a lot of of time waking up the host, as it
cannot go tickless (if the [host] TSC has been marked unstable). On my
laptop I was getting ~40% of wakeups from lguest.

With this patch applied, my laptop is much happier!

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:49 +10:00
Rusty Russell
ebac52524d lguest_devices belongs in lguest_bus.c: it's not i386-specific.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:49 +10:00
Rusty Russell
141341cdae Lguest currently depends on 32-bit x86, not just x86.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:48 +10:00
Jes Sorensen
891ff65ff5 Use copy_to_user() not put_user for struct timespec
Use copy_to_user() when copying a struct timespec to the guest -
put_user() cannot handle two long's in one go on a 64bit arch.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
2007-10-23 15:49:48 +10:00
Rusty Russell
25e82eba3a Remove binfmts.h include from lg.h
It wasn't needed since a very early prototype of lguest.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:47 +10:00
Rusty Russell
d3d1c4bdf1 Normalize config options for guest support
1) Group all the "guest OS" support options together, under a PARAVIRT_GUEST
   menu.
2) Make those options select CONFIG_PARAVIRT, as suggested by Andi.
3) Make kconfig help titles consistent.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Chris Wright <chrisw@sous-sol.org>
2007-10-23 15:49:47 +10:00
Linus Torvalds
fb9fc39517 Merge branch 'xen-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'xen-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xfs: eagerly remove vmap mappings to avoid upsetting Xen
  xen: add some debug output for failed multicalls
  xen: fix incorrect vcpu_register_vcpu_info hypercall argument
  xen: ask the hypervisor how much space it needs reserved
  xen: lock pte pages while pinning/unpinning
  xen: deal with stale cr3 values when unpinning pagetables
  xen: add batch completion callbacks
  xen: yield to IPI target if necessary
  Clean up duplicate includes in arch/i386/xen/
  remove dead code in pgtable_cache_init
  paravirt: clean up lazy mode handling
  paravirt: refactor struct paravirt_ops into smaller pv_*_ops
2007-10-17 11:10:11 -07:00
H. Peter Anvin
30c826451d [x86] remove uses of magic macros for boot_params access
Instead of using magic macros for boot_params access, simply use the
boot_params structure.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2007-10-16 17:38:31 -07:00
Jeremy Fitzhardinge
8965c1c095 paravirt: clean up lazy mode handling
Currently, the set_lazy_mode pv_op is overloaded with 5 functions:
 1. enter lazy cpu mode
 2. leave lazy cpu mode
 3. enter lazy mmu mode
 4. leave lazy mmu mode
 5. flush pending batched operations

This complicates each paravirt backend, since it needs to deal with
all the possible state transitions, handling flushing, etc. In
particular, flushing is quite distinct from the other 4 functions, and
seems to just cause complication.

This patch removes the set_lazy_mode operation, and adds "enter" and
"leave" lazy mode operations on mmu_ops and cpu_ops.  All the logic
associated with enter and leaving lazy states is now in common code
(basically BUG_ONs to make sure that no mode is current when entering
a lazy mode, and make sure that the mode is current when leaving).
Also, flush is handled in a common way, by simply leaving and
re-entering the lazy mode.

The result is that the Xen, lguest and VMI lazy mode implementations
are much simpler.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
2007-10-16 11:51:29 -07:00
Jeremy Fitzhardinge
93b1eab3d2 paravirt: refactor struct paravirt_ops into smaller pv_*_ops
This patch refactors the paravirt_ops structure into groups of
functionally related ops:

pv_info - random info, rather than function entrypoints
pv_init_ops - functions used at boot time (some for module_init too)
pv_misc_ops - lazy mode, which didn't fit well anywhere else
pv_time_ops - time-related functions
pv_cpu_ops - various privileged instruction ops
pv_irq_ops - operations for managing interrupt state
pv_apic_ops - APIC operations
pv_mmu_ops - operations for managing pagetables

There are several motivations for this:

1. Some of these ops will be general to all x86, and some will be
   i386/x86-64 specific.  This makes it easier to share common stuff
   while allowing separate implementations where needed.

2. At the moment we must export all of paravirt_ops, but modules only
   need selected parts of it.  This allows us to export on a case by case
   basis (and also choose which export license we want to apply).

3. Functional groupings make things a bit more readable.

Struct paravirt_ops is now only used as a template to generate
patch-site identifiers, and to extract function pointers for inserting
into jmp/calls when patching.  It is only instantiated when needed.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
2007-10-16 11:51:29 -07:00
Rusty Russell
bbbd2bf00b fix modules oopsing in lguest guests
The assembly templates for lguest guest patching are in the .init.text
section.  This means that modules get patched with "cc cc cc cc" or similar
junk.

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>
2007-09-25 08:51:04 -07:00
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