Commit Graph

225 Commits

Author SHA1 Message Date
Joerg Roedel
c2c63a4939 KVM: SVM: Report emulated SVM features to userspace
This patch implements the reporting of the emulated SVM
features to userspace instead of the real hardware
capabilities. Every real hardware capability needs emulation
in nested svm so the old behavior was broken.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:24 +03:00
Joerg Roedel
d4330ef2fb KVM: x86: Add callback to let modules decide over some supported cpuid bits
This patch adds the get_supported_cpuid callback to
kvm_x86_ops. It will be used in do_cpuid_ent to delegate the
decission about some supported cpuid bits to the
architecture modules.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:23 +03:00
Joerg Roedel
228070b1b3 KVM: SVM: Propagate nested entry failure into guest hypervisor
This patch implements propagation of a failes guest vmrun
back into the guest instead of killing the whole guest.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:21 +03:00
Joerg Roedel
2be4fc7a02 KVM: SVM: Sync cr0 and cr3 to kvm state before nested handling
This patch syncs cr0 and cr3 from the vmcb to the kvm state
before nested intercept handling is done. This allows to
simplify the vmexit path.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:20 +03:00
Joerg Roedel
2041a06a50 KVM: SVM: Make sure rip is synced to vmcb before nested vmexit
This patch fixes a bug where a nested guest always went over
the same instruction because the rip was not advanced on a
nested vmexit.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:18 +03:00
Joerg Roedel
924584ccb0 KVM: SVM: Fix nested nmi handling
The patch introducing nested nmi handling had a bug. The
check does not belong to enable_nmi_window but must be in
nmi_allowed. This patch fixes this.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:17 +03:00
Gleb Natapov
acb5451789 KVM: prevent spurious exit to userspace during task switch emulation.
If kvm_task_switch() fails code exits to userspace without specifying
exit reason, so the previous exit reason is reused by userspace. Fix
this by specifying exit reason correctly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:55 +03:00
Jan Kiszka
e269fb2189 KVM: x86: Push potential exception error code on task switches
When a fault triggers a task switch, the error code, if existent, has to
be pushed on the new task's stack. Implement the missing bits.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:46 +03:00
Gleb Natapov
020df0794f KVM: move DR register access handling into generic code
Currently both SVM and VMX have their own DR handling code. Move it to
x86.c.

Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:39 +03:00
Andre Przywara
6bc31bdc55 KVM: SVM: implement NEXTRIPsave SVM feature
On SVM we set the instruction length of skipped instructions
to hard-coded, well known values, which could be wrong when (bogus,
but valid) prefixes (REX, segment override) are used.
Newer AMD processors (Fam10h 45nm and better, aka. PhenomII or
AthlonII) have an explicit NEXTRIP field in the VMCB containing the
desired information.
Since it is cheap to do so, we use this field to override the guessed
value on newer processors.
A fix for older CPUs would be rather expensive, as it would require
to fetch and partially decode the instruction. As the problem is not
a security issue and needs special, handcrafted code to trigger
(no compiler will ever generate such code), I omit a fix for older
CPUs.
If someone is interested, I have both a patch for these CPUs as well as
demo code triggering this issue: It segfaults under KVM, but runs
perfectly on native Linux.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:38 +03:00
Gleb Natapov
cf8f70bfe3 KVM: x86 emulator: fix in/out emulation.
in/out emulation is broken now. The breakage is different depending
on where IO device resides. If it is in userspace emulator reports
emulation failure since it incorrectly interprets kvm_emulate_pio()
return value. If IO device is in the kernel emulation of 'in' will do
nothing since kvm_emulate_pio() stores result directly into vcpu
registers, so emulator will overwrite result of emulation during
commit of shadowed register.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:25 +03:00
Avi Kivity
5bfd8b5455 KVM: Move kvm_exit tracepoint rip reading inside tracepoint
Reading rip is expensive on vmx, so move it inside the tracepoint so we only
incur the cost if tracing is enabled.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:15:25 +03:00
Joerg Roedel
f71385383f KVM: SVM: Ignore lower 12 bit of nested msrpm_pa
These bits are ignored by the hardware too. Implement this
for nested svm too.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:16 +03:00
Joerg Roedel
ce2ac085ff KVM; SVM: Add correct handling of nested iopm
This patch adds the correct handling of the nested io
permission bitmap. Old behavior was to not lookup the port
in the iopm but only reinject an io intercept to the guest.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:15 +03:00
Joerg Roedel
0d6b35378e KVM: SVM: Use svm_msrpm_offset in nested_svm_exit_handled_msr
There is a generic function now to calculate msrpm offsets.
Use that function in nested_svm_exit_handled_msr() remove
the duplicate logic (which had a bug anyway).

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:13 +03:00
Joerg Roedel
323c3d809b KVM: SVM: Optimize nested svm msrpm merging
This patch optimizes the way the msrpm of the host and the
guest are merged. The old code merged the 2 msrpm pages
completly. This code needed to touch 24kb of memory for that
operation. The optimized variant this patch introduces
merges only the parts where the host msrpm may contain zero
bits. This reduces the amount of memory which is touched to
48 bytes.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:12 +03:00
Joerg Roedel
ac72a9b733 KVM: SVM: Introduce direct access msr list
This patch introduces a list with all msrs a guest might
have direct access to and changes the svm_vcpu_init_msrpm
function to use this list.
It also adds a check to set_msr_interception which triggers
a warning if a developer changes a msr intercept that is not
in the list.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:10 +03:00
Joerg Roedel
455716fa94 KVM: SVM: Move msrpm offset calculation to seperate function
The algorithm to find the offset in the msrpm for a given
msr is needed at other places too. Move that logic to its
own function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:08 +03:00
Joerg Roedel
d24778265a KVM: SVM: Return correct values in nested_svm_exit_handled_msr
The nested_svm_exit_handled_msr() returned an bool which is
a bug. I worked by accident because the exected integer
return values match with the true and false values. This
patch changes the return value to int and let the function
return the correct values.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:07 +03:00
Gleb Natapov
d6ab1ed446 KVM: Drop kvm_get_gdt() in favor of generic linux function
Linux now has native_store_gdt() to do the same. Use it instead of
kvm local version.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:32 +03:00
Joerg Roedel
197717d581 KVM: SVM: Clear exit_info for injected INTR exits
When injecting an vmexit.intr into the nested hypervisor
there might be leftover values in the exit_info fields.
Clear them to not confuse nested hypervisors.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:26 +03:00
Joerg Roedel
7f5d8b5600 KVM: SVM: Handle nested selective_cr0 intercept correctly
If we have the following situation with nested svm:

1. Host KVM intercepts cr0 writes
2. Guest hypervisor intercepts only selective cr0 writes

Then we get an cr0 write intercept which is handled on the
host. But that intercepts may actually be a selective cr0
intercept for the guest. This patch checks for this
condition and injects a selective cr0 intercept if needed.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:23 +03:00
Joerg Roedel
4a810181c8 KVM: SVM: Implement emulation of vm_cr msr
This patch implements the emulation of the vm_cr msr for
nested svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:14 +03:00
Joerg Roedel
2e554e8d67 KVM: SVM: Add kvm_nested_intercepts tracepoint
This patch adds a tracepoint to get information about the
most important intercept bitmasks from the nested vmcb.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:10 +03:00
Joerg Roedel
ecf1405df2 KVM: SVM: Restore tracing of nested vmcb address
A recent change broke tracing of the nested vmcb address. It
was reported as 0 all the time. This patch fixes it.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:07 +03:00
Joerg Roedel
887f500ca1 KVM: SVM: Check for nested intercepts on NMI injection
This patch implements the NMI intercept checking for nested
svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:04 +03:00
Joerg Roedel
0e5cbe368b KVM: SVM: Reset MMU on nested_svm_vmrun for NPT too
Without resetting the MMU the gva_to_pga function will not
work reliably when the vcpu is running in nested context.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:01 +03:00
Joerg Roedel
e02317153e KVM: SVM: Coding style cleanup
This patch removes whitespace errors, fixes comment formats
and most of checkpatch warnings. Now vim does not show
c-space-errors anymore.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:52:58 +03:00
Jan Kiszka
66b7138f91 KVM: SVM: Emulate nRIP feature when reinjecting INT3
When in guest debugging mode, we have to reinject those #BP software
exceptions that are caused by guest-injected INT3. As older AMD
processors do not support the required nRIP VMCB field, try to emulate
it by moving RIP past the instruction on exception injection. Fix it up
again in case the injection failed and we were able to catch this. This
does not work for unintercepted faults, but it is better than doing
nothing.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:00:43 +03:00
Jan Kiszka
116a4752c8 KVM: SVM: Move svm_queue_exception
Move svm_queue_exception past skip_emulated_instruction to allow calling
it later on.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:00:37 +03:00
Jan Kiszka
48005f64d0 KVM: x86: Save&restore interrupt shadow mask
The interrupt shadow created by STI or MOV-SS-like operations is part of
the VCPU state and must be preserved across migration. Transfer it in
the spare padding field of kvm_vcpu_events.interrupt.

As a side effect we now have to make vmx_set_interrupt_shadow robust
against both shadow types being set. Give MOV SS a higher priority and
skip STI in that case to avoid that VMX throws a fault on next entry.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:38:28 +03:00
Joerg Roedel
8fe546547c KVM: SVM: Fix wrong interrupt injection in enable_irq_windows
The nested_svm_intr() function does not execute the vmexit
anymore. Therefore we may still be in the nested state after
that function ran. This patch changes the nested_svm_intr()
function to return wether the irq window could be enabled.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:38:11 +03:00
Joerg Roedel
66a562f7e2 KVM: SVM: Make lazy FPU switching work with nested svm
The new lazy fpu switching code may disable cr0 intercepts
when running nested. This is a bug because the nested
hypervisor may still want to intercept cr0 which will break
in this situation. This patch fixes this issue and makes
lazy fpu switching working with nested svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:28 +03:00
Joerg Roedel
06fc777269 KVM: SVM: Activate nested state only when guest state is complete
Certain functions called during the emulated world switch
behave differently when the vcpu is running nested. This is
not the expected behavior during a world switch emulation.
This patch ensures that the nested state is activated only
if the vcpu is completly in nested state.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:25 +03:00
Joerg Roedel
88ab24adc7 KVM: SVM: Don't sync nested cr8 to lapic and back
This patch makes syncing of the guest tpr to the lapic
conditional on !nested. Otherwise a nested guest using the
TPR could freeze the guest.
Another important change this patch introduces is that the
cr8 intercept bits are no longer ORed at vmrun emulation if
the guest sets VINTR_MASKING in its VMCB. The reason is that
nested cr8 accesses need alway be handled by the nested
hypervisor because they change the shadow version of the
tpr.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:22 +03:00
Joerg Roedel
4c7da8cb43 KVM: SVM: Fix nested msr intercept handling
The nested_svm_exit_handled_msr() function maps only one
page of the guests msr permission bitmap. This patch changes
the code to use kvm_read_guest to fix the bug.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:19 +03:00
Joerg Roedel
6c3bd3d766 KVM: SVM: Annotate nested_svm_map with might_sleep()
The nested_svm_map() function can sleep and must not be
called from atomic context. So annotate that function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:16 +03:00
Joerg Roedel
cdbbdc1210 KVM: SVM: Sync all control registers on nested vmexit
Currently the vmexit emulation does not sync control
registers were the access is typically intercepted by the
nested hypervisor. But we can not count on that intercepts
to sync these registers too and make the code
architecturally more correct.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:13 +03:00
Joerg Roedel
b8e88bc8ff KVM: SVM: Fix schedule-while-atomic on nested exception handling
Move the actual vmexit routine out of code that runs with
irqs and preemption disabled.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:10 +03:00
Joerg Roedel
7597f129d8 KVM: SVM: Don't use kmap_atomic in nested_svm_map
Use of kmap_atomic disables preemption but if we run in
shadow-shadow mode the vmrun emulation executes kvm_set_cr3
which might sleep or fault. So use kmap instead for
nested_svm_map.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:07 +03:00
Gleb Natapov
89a27f4d0e KVM: use desc_ptr struct instead of kvm private descriptor_table
x86 arch defines desc_ptr for idt/gdt pointers, no need to define
another structure in kvm code.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:28 +03:00
Takuya Yoshikawa
b7af404338 KVM: SVM: Fix memory leaks that happen when svm_create_vcpu() fails
svm_create_vcpu() does not free the pages allocated during the creation
when it fails to complete the allocations. This patch fixes it.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-20 12:55:04 +03:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Avi Kivity
59200273c4 KVM: Trace failed msr reads and writes
Record failed msrs reads and writes, and the fact that they failed as well.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:06 -03:00
Avi Kivity
f6801dff23 KVM: Rename vcpu->shadow_efer to efer
None of the other registers have the shadow_ prefix.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:04 -03:00
Avi Kivity
6b52d18605 KVM: Activate fpu on clts
Assume that if the guest executes clts, it knows what it's doing, and load the
guest fpu to prevent an #NM exception.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:04 -03:00
Jan Kiszka
727f5a23e2 KVM: SVM: Trap all debug register accesses
To enable proper debug register emulation under all conditions, trap
access to all DR0..7. This may be optimized later on.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:02 -03:00
Jan Kiszka
c76de350c8 KVM: SVM: Clean up and enhance mov dr emulation
Enhance mov dr instruction emulation used by SVM so that it properly
handles dr4/5: alias to dr6/7 if cr4.de is cleared. Otherwise return
EMULATE_FAIL which will let our only possible caller in that scenario,
ud_interception, re-inject UD.

We do not need to inject faults, SVM does this for us (exceptions take
precedence over instruction interceptions). For the same reason, the
value overflow checks can be removed.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:02 -03:00
Avi Kivity
4610c83cdc KVM: SVM: Lazy fpu with npt
Now that we can allow the guest to play with cr0 when the fpu is loaded,
we can enable lazy fpu when npt is in use.

Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:51 -03:00
Avi Kivity
d225157bc6 KVM: SVM: Selective cr0 intercept
If two conditions apply:
 - no bits outside TS and EM differ between the host and guest cr0
 - the fpu is active

then we can activate the selective cr0 write intercept and drop the
unconditional cr0 read and write intercept, and allow the guest to run
with the host fpu state.  This reduces cr0 exits due to guest fpu management
while the guest fpu is loaded.

Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:51 -03:00