Commit Graph

488 Commits

Author SHA1 Message Date
Ingo Molnar
8302294f43 Merge branch 'tracing/core-v2' into tracing-for-linus
Conflicts:
	include/linux/slub_def.h
	lib/Kconfig.debug
	mm/slob.c
	mm/slub.c
2009-04-02 00:49:02 +02:00
Avi Kivity
16175a796d KVM: VMX: Don't allow uninhibited access to EFER on i386
vmx_set_msr() does not allow i386 guests to touch EFER, but they can still
do so through the default: label in the switch.  If they set EFER_LME, they
can oops the host.

Fix by having EFER access through the normal channel (which will check for
EFER_LME) even on i386.

Reported-and-tested-by: Benjamin Gilbert <bgilbert@cs.cmu.edu>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:15 +02:00
Andrea Arcangeli
4539b35881 KVM: Fix missing smp tlb flush in invlpg
When kvm emulates an invlpg instruction, it can drop a shadow pte, but
leaves the guest tlbs intact.  This can cause memory corruption when
swapping out.

Without this the other cpu can still write to a freed host physical page.
tlb smp flush must happen if rmap_remove is called always before mmu_lock
is released because the VM will take the mmu_lock before it can finally add
the page to the freelist after swapout. mmu notifier makes it safe to flush
the tlb after freeing the page (otherwise it would never be safe) so we can do
a single flush for multiple sptes invalidated.

Cc: stable@kernel.org
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:14 +02:00
Hannes Eder
cded19f396 KVM: fix sparse warnings: Should it be static?
Impact: Make symbols static.

Fix this sparse warnings:
  arch/x86/kvm/mmu.c:992:5: warning: symbol 'mmu_pages_add' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1124:5: warning: symbol 'mmu_pages_next' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1144:6: warning: symbol 'mmu_pages_clear_parents' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2037:5: warning: symbol 'kvm_read_guest_virt' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2067:5: warning: symbol 'kvm_write_guest_virt' was not declared. Should it be static?
  virt/kvm/irq_comm.c:220:5: warning: symbol 'setup_routing_entry' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:14 +02:00
Hannes Eder
d7364a29b3 KVM: fix sparse warnings: context imbalance
Impact: Attribute function with __acquires(...) resp. __releases(...).

Fix this sparse warnings:
  arch/x86/kvm/i8259.c:34:13: warning: context imbalance in 'pic_lock' - wrong count at exit
  arch/x86/kvm/i8259.c:39:13: warning: context imbalance in 'pic_unlock' - unexpected unlock

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:13 +02:00
Amit Shah
41d6af1192 KVM: is_long_mode() should check for EFER.LMA
is_long_mode currently checks the LongModeEnable bit in
EFER instead of the LongModeActive bit. This is wrong, but
we survived this till now since it wasn't triggered. This
breaks guests that go from long mode to compatibility mode.

This is noticed on a solaris guest and fixes bug #1842160

Signed-off-by: Amit Shah <amit.shah@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2009-03-24 11:03:13 +02:00
Amit Shah
401d10dee0 KVM: VMX: Update necessary state when guest enters long mode
setup_msrs() should be called when entering long mode to save the
shadow state for the 64-bit guest state.

Using vmx_set_efer() in enter_lmode() removes some duplicated code
and also ensures we call setup_msrs(). We can safely pass the value
of shadow_efer to vmx_set_efer() as no other bits in the efer change
while enabling long mode (guest first sets EFER.LME, then sets CR0.PG
which causes a vmexit where we activate long mode).

With this fix, is_long_mode() can check for EFER.LMA set instead of
EFER.LME and 5e23049e86dd298b72e206b420513dbc3a240cd9 can be reverted.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:13 +02:00
Joerg Roedel
c5bc224240 KVM: MMU: Fix another largepage memory leak
In the paging_fetch function rmap_remove is called after setting a large
pte to non-present. This causes rmap_remove to not drop the reference to
the large page. The result is a memory leak of that page.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:11 +02:00
Andre Przywara
1fbdc7a585 KVM: SVM: set accessed bit for VMCB segment selectors
In the segment descriptor _cache_ the accessed bit is always set
(although it can be cleared in the descriptor itself). Since Intel
checks for this condition on a VMENTRY, set this bit in the AMD path
to enable cross vendor migration.

Cc: stable@kernel.org
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Acked-By: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:11 +02:00
Gleb Natapov
4925663a07 KVM: Report IRQ injection status to userspace.
IRQ injection status is either -1 (if there was no CPU found
that should except the interrupt because IRQ was masked or
ioapic was misconfigured or ...) or >= 0 in that case the
number indicates to how many CPUs interrupt was injected.
If the value is 0 it means that the interrupt was coalesced
and probably should be reinjected.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:11 +02:00
Joerg Roedel
452425dbaa KVM: MMU: remove assertion in kvm_mmu_alloc_page
The assertion no longer makes sense since we don't clear page tables on
allocation; instead we clear them during prefetch.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:10 +02:00
Joerg Roedel
6bed6b9e84 KVM: MMU: remove redundant check in mmu_set_spte
The following code flow is unnecessary:

	if (largepage)
		was_rmapped = is_large_pte(*shadow_pte);
	 else
	 	was_rmapped = 1;

The is_large_pte() function will always evaluate to one here because the
(largepage && !is_large_pte) case is already handled in the first
if-clause. So we can remove this check and set was_rmapped to one always
here.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:10 +02:00
Gerd Hoffmann
c807660407 KVM: Fix kvmclock on !constant_tsc boxes
kvmclock currently falls apart on machines without constant tsc.
This patch fixes it.  Changes:

  * keep tsc frequency in a per-cpu variable.
  * handle kvmclock update using a new request flag, thus checking
    whenever we need an update each time we enter guest context.
  * use a cpufreq notifier to track frequency changes and force
    kvmclock updates.
  * send ipis to kick cpu out of guest context if needed to make
    sure the guest doesn't see stale values.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:09 +02:00
Sheng Yang
49cd7d2238 KVM: VMX: Use kvm_mmu_page_fault() handle EPT violation mmio
Removed duplicated code.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:09 +02:00
Jan Kiszka
34c33d163f KVM: Drop unused evaluations from string pio handlers
Looks like neither the direction nor the rep prefix are used anymore.
Drop related evaluations from SVM's and VMX's I/O exit handlers.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:08 +02:00
Alexander Graf
1b2fd70c4e KVM: Add FFXSR support
AMD K10 CPUs implement the FFXSR feature that gets enabled using
EFER. Let's check if the virtual CPU description includes that
CPUID feature bit and allow enabling it then.

This is required for Windows Server 2008 in Hyper-V mode.

v2 adds CPUID capability exposure

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:08 +02:00
Marcelo Tosatti
44882eed2e KVM: make irq ack notifications aware of routing table
IRQ ack notifications assume an identity mapping between pin->gsi,
which might not be the case with, for example, HPET.

Translate before acking.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Acked-by: Gleb Natapov <gleb@redhat.com>
2009-03-24 11:03:08 +02:00
Avi Kivity
399ec807dd KVM: Userspace controlled irq routing
Currently KVM has a static routing from GSI numbers to interrupts (namely,
0-15 are mapped 1:1 to both PIC and IOAPIC, and 16:23 are mapped 1:1 to
the IOAPIC).  This is insufficient for several reasons:

- HPET requires non 1:1 mapping for the timer interrupt
- MSIs need a new method to assign interrupt numbers and dispatch them
- ACPI APIC mode needs to be able to reassign the PCI LINK interrupts to the
  ioapics

This patch implements an interrupt routing table (as a linked list, but this
can be easily changed) and a userspace interface to replace the table.  The
routing table is initialized according to the current hardwired mapping.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:06 +02:00
Amit Shah
1935547504 KVM: x86: Fix typos and whitespace errors
Some typos, comments, whitespace errors corrected in the cpuid code

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:05 +02:00
Avi Kivity
5a41accd3f KVM: MMU: Only enable cr4_pge role in shadow mode
Two dimensional paging is only confused by it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:04 +02:00
Avi Kivity
f6e2c02b6d KVM: MMU: Rename "metaphysical" attribute to "direct"
This actually describes what is going on, rather than alerting the reader
that something strange is going on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:04 +02:00
Marcelo Tosatti
9903a927a4 KVM: MMU: drop zeroing on mmu_memory_cache_alloc
Zeroing on mmu_memory_cache_alloc is unnecessary since:

- Smaller areas are pre-allocated with kmem_cache_zalloc.
- Page pointed by ->spt is overwritten with prefetch_page
  and entries in page pointed by ->gfns are initialized
  before reading.

[avi: zeroing pages is unnecessary]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:04 +02:00
Joe Perches
ff81ff10b4 KVM: SVM: Fix typo in has_svm()
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:04 +02:00
Avi Kivity
4780c65904 KVM: Reset PIT irq injection logic when the PIT IRQ is unmasked
While the PIT is masked the guest cannot ack the irq, so the reinject logic
will never allow the interrupt to be injected.

Fix by resetting the reinjection counters on unmask.

Unbreaks Xen.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:03 +02:00
Avi Kivity
5d9b8e30f5 KVM: Add CONFIG_HAVE_KVM_IRQCHIP
Two KVM archs support irqchips and two don't.  Add a Kconfig item to
make selecting between the two models easier.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:02 +02:00
Avi Kivity
4677a3b693 KVM: MMU: Optimize page unshadowing
Using kvm_mmu_lookup_page() will result in multiple scans of the hash chains;
use hlist_for_each_entry_safe() to achieve a single scan instead.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:02 +02:00
Alexander Graf
c8a73f186b KVM: SVM: Add microcode patch level dummy
VMware ESX checks if the microcode level is correct when using a barcelona
CPU, in order to see if it actually can use SVM. Let's tell it we're on the
safe side...

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:02 +02:00
Avi Kivity
269e05e485 KVM: Properly lock PIT creation
Otherwise, two threads can create a PIT in parallel and cause a memory leak.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:01 +02:00
Avi Kivity
a77ab5ead5 KVM: x86 emulator: implement 'ret far' instruction (opcode 0xcb)
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:01 +02:00
Avi Kivity
8b3079a5c0 KVM: VMX: When emulating on invalid vmx state, don't return to userspace unnecessarily
If we aren't doing mmio there's no need to exit to userspace (which will
just be confused).

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:00 +02:00
Avi Kivity
350f69dcd1 KVM: x86 emulator: Make emulate_pop() a little more generic
Allow emulate_pop() to read into arbitrary memory rather than just the
source operand.  Needed for complicated instructions like far returns.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:00 +02:00
Avi Kivity
10f32d84c7 KVM: VMX: Prevent exit handler from running if emulating due to invalid state
If we've just emulated an instruction, we won't have any valid exit
reason and associated information.

Fix by moving the clearing of the emulation_required flag to the exit handler.
This way the exit handler can notice that we've been emulating and abort
early.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:00 +02:00
Avi Kivity
9fd4a3b7a4 KVM: VMX: don't clobber segment AR if emulating invalid state
The ususable bit is important for determining state validity; don't
clobber it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:00 +02:00
Avi Kivity
1872a3f411 KVM: VMX: Fix guest state validity checks
The vmx guest state validity checks are full of bugs.  Make them
conform to the manual.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:59 +02:00
Marcelo Tosatti
52d939a0bf KVM: PIT: provide an option to disable interrupt reinjection
Certain clocks (such as TSC) in older 2.6 guests overaccount for lost
ticks, causing severe time drift. Interrupt reinjection magnifies the
problem.

Provide an option to disable it.

[avi: allow room for expansion in case we want to disable reinjection
      of other timers]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:55 +02:00
Avi Kivity
61a6bd672b KVM: Fallback support for MSR_VM_HSAVE_PA
Since we advertise MSR_VM_HSAVE_PA, userspace will attempt to read it
even on Intel.  Implement fake support for this MSR to avoid the
warnings.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:54 +02:00
Izik Eidus
0f34607440 KVM: remove the vmap usage
vmap() on guest pages hides those pages from the Linux mm for an extended
(userspace determined) amount of time.  Get rid of it.

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:54 +02:00
Izik Eidus
77c2002e7c KVM: introduce kvm_read_guest_virt, kvm_write_guest_virt
This commit change the name of emulator_read_std into kvm_read_guest_virt,
and add new function name kvm_write_guest_virt that allow writing into a
guest virtual address.

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:54 +02:00
Marcelo Tosatti
53f658b3c3 KVM: VMX: initialize TSC offset relative to vm creation time
VMX initializes the TSC offset for each vcpu at different times, and
also reinitializes it for vcpus other than 0 on APIC SIPI message.

This bug causes the TSC's to appear unsynchronized in the guest, even if
the host is good.

Older Linux kernels don't handle the situation very well, so
gettimeofday is likely to go backwards in time:

http://www.mail-archive.com/kvm@vger.kernel.org/msg02955.html
http://sourceforge.net/tracker/index.php?func=detail&aid=2025534&group_id=180599&atid=893831

Fix it by initializating the offset of each vcpu relative to vm creation
time, and moving it from vmx_vcpu_reset to vmx_vcpu_setup, out of the
APIC MP init path.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:53 +02:00
Avi Kivity
e8c4a4e8a7 KVM: MMU: Drop walk_shadow()
No longer used.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:53 +02:00
Avi Kivity
a461930bc3 KVM: MMU: Replace walk_shadow() by for_each_shadow_entry() in invlpg()
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:53 +02:00
Avi Kivity
e7a04c99b5 KVM: MMU: Replace walk_shadow() by for_each_shadow_entry() in fetch()
Effectively reverting to the pre walk_shadow() version -- but now
with the reusable for_each().

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:52 +02:00
Avi Kivity
9f652d21c3 KVM: MMU: Use for_each_shadow_entry() in __direct_map()
Eliminating a callback and a useless structure.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:52 +02:00
Avi Kivity
2d11123a77 KVM: MMU: Add for_each_shadow_entry(), a simpler alternative to walk_shadow()
Using a for_each loop style removes the need to write callback and nasty
casts.

Implement the walk_shadow() using the for_each_shadow_entry().

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:52 +02:00
Avi Kivity
2b3d2a2060 KVM: Fix vmload and friends misinterpreted as lidt
The AMD SVM instruction family all overload the 0f 01 /3 opcode, further
multiplexing on the three r/m bits.  But the code decided that anything that
isn't a vmmcall must be an lidt (which shares the 0f 01 /3 opcode, for the
case that mod = 3).

Fix by aborting emulation if this isn't a vmmcall.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:51 +02:00
Avi Kivity
e207831804 KVM: MMU: Initialize a shadow page's global attribute from cr4.pge
If cr4.pge is cleared, we ought to treat any ptes in the page as non-global.
This allows us to remove the check from set_spte().

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:51 +02:00
Avi Kivity
2f0b3d60b2 KVM: MMU: Segregate mmu pages created with different cr4.pge settings
Don't allow a vcpu with cr4.pge cleared to use a shadow page created with
cr4.pge set; this might cause a cr3 switch not to sync ptes that have the
global bit set (the global bit has no effect if !cr4.pge).

This can only occur on smp with different cr4.pge settings for different
vcpus (since a cr4 change will resync the shadow ptes), but there's no
cost to being correct here.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:51 +02:00
Avi Kivity
a770f6f28b KVM: MMU: Inherit a shadow page's guest level count from vcpu setup
Instead of "calculating" it on every shadow page allocation, set it once
when switching modes, and copy it when allocating pages.

This doesn't buy us much, but sets up the stage for inheriting more
information related to the mmu setup.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:51 +02:00
Jan Kiszka
ae675ef01c KVM: x86: Wire-up hardware breakpoints for guest debugging
Add the remaining bits to make use of debug registers also for guest
debugging, thus enabling the use of hardware breakpoints and
watchpoints.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:50 +02:00
Jan Kiszka
42dbaa5a05 KVM: x86: Virtualize debug registers
So far KVM only had basic x86 debug register support, once introduced to
realize guest debugging that way. The guest itself was not able to use
those registers.

This patch now adds (almost) full support for guest self-debugging via
hardware registers. It refactors the code, moving generic parts out of
SVM (VMX was already cleaned up by the KVM_SET_GUEST_DEBUG patches), and
it ensures that the registers are properly switched between host and
guest.

This patch also prepares debug register usage by the host. The latter
will (once wired-up by the following patch) allow for hardware
breakpoints/watchpoints in guest code. If this is enabled, the guest
will only see faked debug registers without functionality, but with
content reflecting the guest's modifications.

Tested on Intel only, but SVM /should/ work as well, but who knows...

Known limitations: Trapping on tss switch won't work - most probably on
Intel.

Credits also go to Joerg Roedel - I used his once posted debugging
series as platform for this patch.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:49 +02:00