Commit Graph

446 Commits

Author SHA1 Message Date
Avi Kivity c5ca8e572c KVM: VMX: Don't VMREAD VM_EXIT_INTR_INFO unconditionally
Only read it if we're going to use it later.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity 00eba012d5 KVM: VMX: Refactor vmx_complete_atomic_exit()
Move the exit reason checks to the front of the function, for early
exit in the common case.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity f9902069c4 KVM: VMX: Qualify check for host NMI
Check for the exit reason first; this allows us, later,
to avoid a VMREAD for VM_EXIT_INTR_INFO_FIELD.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity 9d58b93192 KVM: VMX: Avoid vmx_recover_nmi_blocking() when unneeded
When we haven't injected an interrupt, we don't need to recover
the nmi blocking state (since the guest can't set it by itself).
This allows us to avoid a VMREAD later on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity 69c7302890 KVM: VMX: Cache cpl
We may read the cpl quite often in the same vmexit (instruction privilege
check, memory access checks for instruction and operands), so we gain
a bit if we cache the value.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity f4c63e5d5a KVM: VMX: Optimize vmx_get_cpl()
In long mode, vm86 mode is disallowed, so we need not check for
it.  Reading rflags.vm may require a VMREAD, so it is expensive.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity 6de12732c4 KVM: VMX: Optimize vmx_get_rflags()
If called several times within the same exit, return cached results.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity f6e7847589 KVM: Use kvm_get_rflags() and kvm_set_rflags() instead of the raw versions
Some rflags bits are owned by the host, not guest, so we need to use
kvm_get_rflags() to strip those bits away or kvm_set_rflags() to add them
back.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Gleb Natapov 776e58ea3d KVM: unbreak userspace that does not sets tss address
Commit 6440e5967bc broke old userspaces that do not set tss address
before entering vcpu. Unbreak it by setting tss address to a safe
value on the first vcpu entry. New userspaces should set tss address,
so print warning in case it doesn't.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-17 13:08:35 -03:00
Xiao Guangrong 40dcaa9f69 KVM: fix rcu usage in init_rmode_* functions
fix:
[ 3494.671786] stack backtrace:
[ 3494.671789] Pid: 10527, comm: qemu-system-x86 Not tainted 2.6.38-rc6+ #23
[ 3494.671790] Call Trace:
[ 3494.671796]  [] ? lockdep_rcu_dereference+0x9d/0xa5
[ 3494.671826]  [] ? kvm_memslots+0x6b/0x73 [kvm]
[ 3494.671834]  [] ? gfn_to_memslot+0x16/0x4f [kvm]
[ 3494.671843]  [] ? gfn_to_hva+0x16/0x27 [kvm]
[ 3494.671851]  [] ? kvm_write_guest_page+0x31/0x83 [kvm]
[ 3494.671861]  [] ? kvm_clear_guest_page+0x1a/0x1c [kvm]
[ 3494.671867]  [] ? vmx_set_tss_addr+0x83/0x122 [kvm_intel]

and:
[ 8328.789599] stack backtrace:
[ 8328.789601] Pid: 18736, comm: qemu-system-x86 Not tainted 2.6.38-rc6+ #23
[ 8328.789603] Call Trace:
[ 8328.789609]  [] ? lockdep_rcu_dereference+0x9d/0xa5
[ 8328.789621]  [] ? kvm_memslots+0x6b/0x73 [kvm]
[ 8328.789628]  [] ? gfn_to_memslot+0x16/0x4f [kvm]
[ 8328.789635]  [] ? gfn_to_hva+0x16/0x27 [kvm]
[ 8328.789643]  [] ? kvm_write_guest_page+0x31/0x83 [kvm]
[ 8328.789699]  [] ? kvm_clear_guest_page+0x1a/0x1c [kvm]
[ 8328.789713]  [] ? vmx_create_vcpu+0x316/0x3c8 [kvm_intel]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:34 -03:00
Takuya Yoshikawa afc20184b7 KVM: x86: Remove useless regs_page pointer from kvm_lapic
Access to this page is mostly done through the regs member which holds
the address to this page.  The exceptions are in vmx_vcpu_reset() and
kvm_free_lapic() and these both can easily be converted to using regs.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:33 -03:00
Gleb Natapov 93ea5388ea KVM: VMX: Initialize vm86 TSS only once.
Currently vm86 task is initialized on each real mode entry and vcpu
reset. Initialization is done by zeroing TSS and updating relevant
fields. But since all vcpus are using the same TSS there is a race where
one vcpu may use TSS while other vcpu is initializing it, so the vcpu
that uses TSS will see wrong TSS content and will behave incorrectly.
Fix that by initializing TSS only once.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:31 -03:00
Gleb Natapov a8ba6c2622 KVM: VMX: update live TR selector if it changes in real mode
When rmode.vm86 is active TR descriptor is updated with vm86 task values,
but selector is left intact. vmx_set_segment() makes sure that if TR
register is written into while vm86 is active the new values are saved
for use after vm86 is deactivated, but since selector is not updated on
vm86 activation/deactivation new value is lost. Fix this by writing new
selector into vmcs immediately.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:31 -03:00
Lai Jiangshan a3b5ba49a8 KVM: VMX: add the __noclone attribute to vmx_vcpu_run
The changelog of 104f226 said "adds the __noclone attribute",
but it was missing in its patch. I think it is still needed.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-17 13:08:31 -03:00
Joseph Cihula 23f3e99132 KVM: VMX: fix detection of BIOS disabling VMX
This patch fixes the logic used to detect whether BIOS has disabled VMX, for
the case where VMX is enabled only under SMX, but tboot is not active.

Signed-off-by:  Joseph Cihula <joseph.cihula@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:30 -03:00
Avi Kivity 40712faeb8 KVM: VMX: Avoid atomic operation in vmx_vcpu_run
Instead of exchanging the guest and host rcx, have separate storage
for each.  This allows us to avoid using the xchg instruction, which
is is a little slower than normal operations.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-17 13:08:26 -03:00
Avi Kivity 1c696d0e1b KVM: VMX: Simplify saving guest rcx in vmx_vcpu_run
Change

  push top-of-stack
  pop guest-rcx
  pop dummy

to

  pop guest-rcx

which is the same thing, only simpler.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-17 13:08:25 -03:00
Rik van Riel 00c25bce02 KVM: VMX: increase ple_gap default to 128
On some CPUs, a ple_gap of 41 is simply insufficient to ever trigger
PLE exits, even with the minimalistic PLE test from kvm-unit-tests.

http://git.kernel.org/?p=virt/kvm/kvm-unit-tests.git;a=commitdiff;h=eda71b28fa122203e316483b35f37aaacd42f545

For example, the Xeon X5670 CPU needs a ple_gap of at least 48 in
order to get pause loop exits:

# modprobe kvm_intel ple_gap=47
# taskset 1 /usr/local/bin/qemu-system-x86_64 \
  -device testdev,chardev=log -chardev stdio,id=log \
  -kernel x86/vmexit.flat -append ple-round-robin -smp 2
VNC server running on `::1:5900'
enabling apic
enabling apic
ple-round-robin 58298446
# rmmod kvm_intel
# modprobe kvm_intel ple_gap=48
# taskset 1 /usr/local/bin/qemu-system-x86_64 \
   -device testdev,chardev=log -chardev stdio,id=log \
   -kernel x86/vmexit.flat -append ple-round-robin -smp 2
VNC server running on `::1:5900'
enabling apic
enabling apic
ple-round-robin 36616

Increase the ple_gap to 128 to be on the safe side.

Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Zhai, Edwin <edwin.zhai@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:25 -03:00
Avi Kivity a917949935 KVM: VMX: Avoid leaking fake realmode state to userspace
When emulating real mode, we fake some state:

 - tr.base points to a fake vm86 tss
 - segment registers are made to conform to vm86 restrictions

change vmx_get_segment() not to expose this fake state to userspace;
instead, return the original state.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-17 13:08:25 -03:00
Avi Kivity d0ba64f9b4 KVM: VMX: Save and restore tr selector across mode switches
When emulating real mode we play with tr hidden state, but leave
tr.selector alone.  That works well, except for save/restore, since
loading TR writes it to the hidden state in vmx->rmode.

Fix by also saving and restoring the tr selector; this makes things
more consistent and allows migration to work during the early
boot stages of Windows XP.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-03-17 13:08:25 -03:00
Gleb Natapov 444e863d13 KVM: VMX: when entering real mode align segment base to 16 bytes
VMX checks that base is equal segment shifted 4 bits left. Otherwise
guest entry fails.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:31:20 +02:00
Avi Kivity aff48baa34 KVM: Fetch guest cr3 from hardware on demand
Instead of syncing the guest cr3 every exit, which is expensince on vmx
with ept enabled, sync it only on demand.

[sheng: fix incorrect cr3 seen by Windows XP]

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:31:16 +02:00
Avi Kivity 9f8fe5043f KVM: Replace reads of vcpu->arch.cr3 by an accessor
This allows us to keep cr3 in the VMCS, later on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:31:15 +02:00
Avi Kivity 16d8f72f70 KVM: VMX: Correct asm constraint in vmcs_load()/vmcs_clear()
'error' is byte sized, so use a byte register constraint.

Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:31:12 +02:00
Avi Kivity 110312c84b KVM: VMX: Optimize atomic EFER load
When NX is enabled on the host but not on the guest, we use the entry/exit
msr load facility, which is slow.  Optimize it to use entry/exit efer load,
which is ~1200 cycles faster.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:31:09 +02:00
Andre Przywara dc25e89e07 KVM: SVM: copy instruction bytes from VMCB
In case of a nested page fault or an intercepted #PF newer SVM
implementations provide a copy of the faulting instruction bytes
in the VMCB.
Use these bytes to feed the instruction emulator and avoid the costly
guest instruction fetch in this case.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:31:07 +02:00
Andre Przywara 51d8b66199 KVM: cleanup emulate_instruction
emulate_instruction had many callers, but only one used all
parameters. One parameter was unused, another one is now
hidden by a wrapper function (required for a future addition
anyway), so most callers use now a shorter parameter list.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:31:00 +02:00
Andre Przywara db8fcefaa7 KVM: move complete_insn_gp() into x86.c
move the complete_insn_gp() helper function out of the VMX part
into the generic x86 part to make it usable by SVM.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:30:59 +02:00
Andre Przywara eea1cff9ab KVM: x86: fix CR8 handling
The handling of CR8 writes in KVM is currently somewhat cumbersome.
This patch makes it look like the other CR register handlers
and fixes a possible issue in VMX, where the RIP would be incremented
despite an injected #GP.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:30:58 +02:00
Anthony Liguori 443381a828 KVM: VMX: add module parameter to avoid trapping HLT instructions (v5)
In certain use-cases, we want to allocate guests fixed time slices where idle
guest cycles leave the machine idling.  There are many approaches to achieve
this but the most direct is to simply avoid trapping the HLT instruction which
lets the guest directly execute the instruction putting the processor to sleep.

Introduce this as a module-level option for kvm-vmx.ko since if you do this
for one guest, you probably want to do it for all.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:30:46 +02:00
Avi Kivity a295673aba KVM: VMX: Return 0 from a failed VMREAD
If we execute VMREAD during reboot we'll just skip over it.  Instead of
returning garbage, return 0, which has a much smaller chance of confusing
the code.  Otherwise we risk a flood of debug printk()s which block the
reboot process if a serial console or netconsole is enabled.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:30:20 +02:00
Avi Kivity 586f960796 KVM: Add instruction-set-specific exit qualifications to kvm_exit trace
The exit reason alone is insufficient to understand exactly why an exit
occured; add ISA-specific trace parameters for additional information.

Because fetching these parameters is expensive on vmx, and because these
parameters are fetched even if tracing is disabled, we fetch the
parameters via a callback instead of as traditional trace arguments.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:29:41 +02:00
Avi Kivity aa17911e3c KVM: Record instruction set in kvm_exit tracepoint
exit_reason's meaning depend on the instruction set; record it so a trace
taken on one machine can be interpreted on another.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:29:40 +02:00
Avi Kivity 104f226bfd KVM: VMX: Fold __vmx_vcpu_run() into vmx_vcpu_run()
cea15c2 ("KVM: Move KVM context switch into own function") split vmx_vcpu_run()
to prevent multiple copies of the context switch from being generated (causing
problems due to a label).  This patch folds them back together again and adds
the __noclone attribute to prevent the label from being duplicated.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:29:37 +02:00
Shane Wang f9335afea5 KVM: VMX: Inform user about INTEL_TXT dependency
Inform user to either disable TXT in the BIOS or do TXT launch
with tboot before enabling KVM since some BIOSes do not set
FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX bit when TXT is enabled.

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:29:31 +02:00
Avi Kivity 30bd0c4c6c KVM: VMX: Disallow NMI while blocked by STI
While not mandated by the spec, Linux relies on NMI being blocked by an
IF-enabling STI.  VMX also refuses to enter a guest in this state, at
least on some implementations.

Disallow NMI while blocked by STI by checking for the condition, and
requesting an interrupt window exit if it occurs.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:29:04 +02:00
Gleb Natapov ec25d5e66e KVM: handle exit due to INVD in VMX
Currently the exit is unhandled, so guest halts with error if it tries
to execute INVD instruction. Call into emulator when INVD instruction
is executed by a guest instead. This instruction is not needed by ordinary
guests, but firmware (like OpenBIOS) use it and fail.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:28:53 +02:00
Marcelo Tosatti ff1fcb9ebd KVM: VMX: remove setting of shadow_base_ptes for EPT
The EPT present/writable bits use the same position as normal
pagetable bits.

Since direct_map passes ACC_ALL to mmu_set_spte, thus always setting
the writable bit on sptes, use the generic PT_PRESENT shadow_base_pte.

Also pass present/writable error code information from EPT violation
to generic pagefault handler.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-01-12 11:23:37 +02:00
Andi Kleen f56f536956 KVM: Move KVM context switch into own function
gcc 4.5 with some special options is able to duplicate the VMX
context switch asm in vmx_vcpu_run(). This results in a compile error
because the inline asm sequence uses an on local label. The non local
label is needed because other code wants to set up the return address.

This patch moves the asm code into an own function and marks
that explicitely noinline to avoid this problem.

Better would be probably to just move it into an .S file.

The diff looks worse than the change really is, it's all just
code movement and no logic change.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:23:26 +02:00
Joerg Roedel 24d1b15f72 KVM: SVM: Do not report xsave in supported cpuid
To support xsave properly for the guest the SVM module need
software support for it. As long as this is not present do
not report the xsave as supported feature in cpuid.
As a side-effect this patch moves the bit() helper function
into the x86.h file so that it can be used in svm.c too.

KVM-Stable-Tag.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-12-08 17:28:37 +02:00
Avi Kivity c8770e7ba6 KVM: VMX: Fix host userspace gsbase corruption
We now use load_gs_index() to load gs safely; unfortunately this also
changes MSR_KERNEL_GS_BASE, which we managed separately.  This resulted
in confusion and breakage running 32-bit host userspace on a 64-bit kernel.

Fix by
- saving guest MSR_KERNEL_GS_BASE before we we reload the host's gs
- doing the host save/load unconditionally, instead of only when in guest
  long mode

Things can be cleaned up further, but this is the minmal fix for now.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-11-17 19:48:05 -02:00
Avi Kivity 0a77fe4c18 KVM: Correct ordering of ldt reload wrt fs/gs reload
If fs or gs refer to the ldt, they must be reloaded after the ldt.  Reorder
the code to that effect.

Userspace code that uses the ldt with kvm is nonexistent, so this doesn't fix
a user-visible bug.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-11-17 19:47:59 -02:00
Nicolas Kaiser 9611c18777 KVM: fix typo in copyright notice
Fix typo in copyright notice.

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:53:14 +02:00
Jan Kiszka 07d6f555d5 KVM: VMX: Add AX to list of registers clobbered by guest switch
By chance this caused no harm so far. We overwrite AX during switch
to/from guest context, so we must declare this.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:53:07 +02:00
Avi Kivity 49e9d557f9 KVM: VMX: Respect interrupt window in big real mode
If an interrupt is pending, we need to stop emulation so we
can inject it.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:53:02 +02:00
Mohammed Gamal a92601bb70 KVM: VMX: Emulated real mode interrupt injection
Replace the inject-as-software-interrupt hack we currently have with
emulated injection.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:53:01 +02:00
Avi Kivity 625831a3f4 KVM: VMX: Move fixup_rmode_irq() to avoid forward declaration
No code changes.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:54 +02:00
Avi Kivity b463a6f744 KVM: Non-atomic interrupt injection
Change the interrupt injection code to work from preemptible, interrupts
enabled context.  This works by adding a ->cancel_injection() operation
that undoes an injection in case we were not able to actually enter the guest
(this condition could never happen with atomic injection).

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:54 +02:00
Avi Kivity 83422e17c1 KVM: VMX: Parameterize vmx_complete_interrupts() for both exit and entry
Currently vmx_complete_interrupts() can decode event information from vmx
exit fields into the generic kvm event queues.  Make it able to decode
the information from the entry fields as well by parametrizing it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:52 +02:00
Avi Kivity 537b37e267 KVM: VMX: Move real-mode interrupt injection fixup to vmx_complete_interrupts()
This allows reuse of vmx_complete_interrupts() for cancelling injections.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:51 +02:00
Avi Kivity 51aa01d13d KVM: VMX: Split up vmx_complete_interrupts()
vmx_complete_interrupts() does too much, split it up:
 - vmx_vcpu_run() gets the "cache important vmcs fields" part
 - a new vmx_complete_atomic_exit() gets the parts that must be done atomically
 - a new vmx_recover_nmi_blocking() does what its name says
 - vmx_complete_interrupts() retains the event injection recovery code

This helps in reducing the work done in atomic context.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:51 +02:00
Avi Kivity 3842d135ff KVM: Check for pending events before attempting injection
Instead of blindly attempting to inject an event before each guest entry,
check for a possible event first in vcpu->requests.  Sites that can trigger
event injection are modified to set KVM_REQ_EVENT:

- interrupt, nmi window opening
- ppr updates
- i8259 output changes
- local apic irr changes
- rflags updates
- gif flag set
- event set on exit

This improves non-injecting entry performance, and sets the stage for
non-atomic injection.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:50 +02:00
Joerg Roedel ff03a073e7 KVM: MMU: Add kvm_mmu parameter to load_pdptrs function
This function need to be able to load the pdptrs from any
mmu context currently in use. So change this function to
take an kvm_mmu parameter to fit these needs.
As a side effect this patch also moves the cached pdptrs
from vcpu_arch into the kvm_mmu struct.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:41 +02:00
Joerg Roedel 1c97f0a04c KVM: X86: Introduce a tdp_set_cr3 function
This patch introduces a special set_tdp_cr3 function pointer
in kvm_x86_ops which is only used for tpd enabled mmu
contexts. This allows to remove some hacks from svm code.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:52:30 +02:00
Zachary Amsden e48672fa25 KVM: x86: Unify TSC logic
Move the TSC control logic from the vendor backends into x86.c
by adding adjust_tsc_offset to x86 ops.  Now all TSC decisions
can be done in one place.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:23 +02:00
Zachary Amsden 99e3e30aee KVM: x86: Move TSC offset writes to common code
Also, ensure that the storing of the offset and the reading of the TSC
are never preempted by taking a spinlock.  While the lock is overkill
now, it is useful later in this patch series.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:22 +02:00
Zachary Amsden f4e1b3c8bd KVM: x86: Convert TSC writes to TSC offset writes
Change svm / vmx to be the same internally and write TSC offset
instead of bare TSC in helper functions.  Isolated as a single
patch to contain code movement.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:22 +02:00
Zachary Amsden ae38436b78 KVM: x86: Drop vm_init_tsc
This is used only by the VMX code, and is not done properly;
if the TSC is indeed backwards, it is out of sync, and will
need proper handling in the logic at each and every CPU change.
For now, drop this test during init as misguided.

Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:51:21 +02:00
Avi Kivity d359192fea KVM: VMX: Use host_gdt variable wherever we need the host gdt
Now that we have the host gdt conveniently stored in a variable, make use
of it instead of querying the cpu.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-24 10:50:01 +02:00
Avi Kivity 9581d442b9 KVM: Fix fs/gs reload oops with invalid ldt
kvm reloads the host's fs and gs blindly, however the underlying segment
descriptors may be invalid due to the user modifying the ldt after loading
them.

Fix by using the safe accessors (loadsegment() and load_gs_index()) instead
of home grown unsafe versions.

This is CVE-2010-3698.

KVM-Stable-Tag.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-10-19 14:21:45 -02:00
Linus Torvalds d9a73c0016 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  um, x86: Cast to (u64 *) inside set_64bit()
  x86-32, asm: Directly access per-cpu GDT
  x86-64, asm: Directly access per-cpu IST
  x86, asm: Merge cmpxchg_486_u64() and cmpxchg8b_emu()
  x86, asm: Move cmpxchg emulation code to arch/x86/lib
  x86, asm: Clean up and simplify <asm/cmpxchg.h>
  x86, asm: Clean up and simplify set_64bit()
  x86: Add memory modify constraints to xchg() and cmpxchg()
  x86-64: Simplify loading initial_gs
  x86: Use symbolic MSR names
  x86: Remove redundant K6 MSRs
2010-08-06 10:07:34 -07:00
Avi Kivity 3444d7da18 KVM: VMX: Fix host GDT.LIMIT corruption
vmx does not restore GDT.LIMIT to the host value, instead it sets it to 64KB.
This means host userspace can learn a few bits of host memory.

Fix by reloading GDTR when we load other host state.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-02 08:10:18 +03:00
Xiao Guangrong dd180b3e90 KVM: VMX: fix tlb flush with invalid root
Commit 341d9b535b6c simplify reload logic while entry guest mode, it
can avoid unnecessary sync-root if KVM_REQ_MMU_RELOAD and
KVM_REQ_MMU_SYNC both set.

But, it cause a issue that when we handle 'KVM_REQ_TLB_FLUSH', the
root is invalid, it is triggered during my test:

Kernel BUG at ffffffffa00212b8 [verbose debug info unavailable]
......

Fixed by directly return if the root is not ready.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-02 06:40:16 +03:00
Sheng Yang f5f48ee15c KVM: VMX: Execute WBINVD to keep data consistency with assigned devices
Some guest device driver may leverage the "Non-Snoop" I/O, and explicitly
WBINVD or CLFLUSH to a RAM space. Since migration may occur before WBINVD or
CLFLUSH, we need to maintain data consistency either by:
1: flushing cache (wbinvd) when the guest is scheduled out if there is no
wbinvd exit, or
2: execute wbinvd on all dirty physical CPUs when guest wbinvd exits.

Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:47:21 +03:00
Avi Kivity a8eeb04a44 KVM: Add mini-API for vcpu->requests
Makes it a little more readable and hackable.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:47:05 +03:00
Avi Kivity 2390218b6a KVM: Fix mov cr3 #GP at wrong instruction
On Intel, we call skip_emulated_instruction() even if we injected a #GP,
resulting in the #GP pointing at the wrong address.

Fix by injecting the exception and skipping the instruction at the same place,
so we can do just one or the other.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:46:35 +03:00
Avi Kivity a83b29c6ad KVM: Fix mov cr4 #GP at wrong instruction
On Intel, we call skip_emulated_instruction() even if we injected a #GP,
resulting in the #GP pointing at the wrong address.

Fix by injecting the exception and skipping the instruction at the same place,
so we can do just one or the other.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:46:34 +03:00
Avi Kivity 49a9b07edc KVM: Fix mov cr0 #GP at wrong instruction
On Intel, we call skip_emulated_instruction() even if we injected a #GP,
resulting in the #GP pointing at the wrong address.

Fix by injecting the exception and skipping the instruction at the same place,
so we can do just one or the other.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:46:32 +03:00
Dexuan Cui 2acf923e38 KVM: VMX: Enable XSAVE/XRSTOR for guest
This patch enable guest to use XSAVE/XRSTOR instructions.

We assume that host_xcr0 would use all possible bits that OS supported.

And we loaded xcr0 in the same way we handled fpu - do it as late as we can.

Signed-off-by: Dexuan Cui <dexuan.cui@intel.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:46:31 +03:00
Avi Kivity f495c6e5e8 KVM: VMX: Fix incorrect rcu deref in rmode_tss_base()
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:46:30 +03:00
Xiao Guangrong 4b9d3a0451 KVM: VMX: fix rcu usage warning in init_rmode()
fix:

[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
include/linux/kvm_host.h:258 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 1
1 lock held by qemu-system-x86/3796:
 #0:  (&vcpu->mutex){+.+.+.}, at: [<ffffffffa0217fd8>] vcpu_load+0x1a/0x66 [kvm]

stack backtrace:
Pid: 3796, comm: qemu-system-x86 Not tainted 2.6.34 #25
Call Trace:
 [<ffffffff81070ed1>] lockdep_rcu_dereference+0x9d/0xa5
 [<ffffffffa0214fdf>] gfn_to_memslot_unaliased+0x65/0xa0 [kvm]
 [<ffffffffa0216139>] gfn_to_hva+0x22/0x4c [kvm]
 [<ffffffffa0216217>] kvm_write_guest_page+0x2a/0x7f [kvm]
 [<ffffffffa0216286>] kvm_clear_guest_page+0x1a/0x1c [kvm]
 [<ffffffffa0278239>] init_rmode+0x3b/0x180 [kvm_intel]
 [<ffffffffa02786ce>] vmx_set_cr0+0x350/0x4d3 [kvm_intel]
 [<ffffffffa02274ff>] kvm_arch_vcpu_ioctl_set_sregs+0x122/0x31a [kvm]
 [<ffffffffa021859c>] kvm_vcpu_ioctl+0x578/0xa3d [kvm]
 [<ffffffff8106624c>] ? cpu_clock+0x2d/0x40
 [<ffffffff810f7d86>] ? fget_light+0x244/0x28e
 [<ffffffff810709b9>] ? trace_hardirqs_off_caller+0x1f/0x10e
 [<ffffffff8110501b>] vfs_ioctl+0x32/0xa6
 [<ffffffff81105597>] do_vfs_ioctl+0x47f/0x4b8
 [<ffffffff813ae654>] ? sub_preempt_count+0xa3/0xb7
 [<ffffffff810f7da8>] ? fget_light+0x266/0x28e
 [<ffffffff810f7c53>] ? fget_light+0x111/0x28e
 [<ffffffff81105617>] sys_ioctl+0x47/0x6a
 [<ffffffff81002c1b>] system_call_fastpath+0x16/0x1b

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:46:23 +03:00
Gui Jianfeng 1760dd4939 KVM: VMX: rename vpid_sync_vcpu_all() to vpid_sync_vcpu_single()
The name "pid_sync_vcpu_all" isn't appropriate since it just affect
a single vpid, so rename it to vpid_sync_vcpu_single().

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:46:16 +03:00
Gui Jianfeng b9d762fa79 KVM: VMX: Add all-context INVVPID type support
Add all-context INVVPID type support.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:46:04 +03:00
Gui Jianfeng 518c8aee5c KVM: VMX: Make sure single type invvpid is supported before issuing invvpid instruction
According to SDM, we need check whether single-context INVVPID type is supported
before issuing invvpid instruction.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Reviewed-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:39:26 +03:00
Sheng Yang 4bc9b98281 KVM: VMX: Enforce EPT pagetable level checking
We only support 4 levels EPT pagetable now.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:39:25 +03:00
Mohammed Gamal 5120702e73 KVM: VMX: Properly return error to userspace on vmentry failure
The vmexit handler returns KVM_EXIT_UNKNOWN since there is no handler
for vmentry failures. This intercepts vmentry failures and returns
KVM_FAIL_ENTRY to userspace instead.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:39:24 +03:00
Jan Kiszka 10ab25cd6b KVM: x86: Propagate fpu_alloc errors
Memory allocation may fail. Propagate such errors.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:39:22 +03:00
Avi Kivity 221d059d15 KVM: Update Red Hat copyrights
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:51 +03:00
Dongxiao Xu 4610c9cc6d KVM: VMX: VMXON/VMXOFF usage changes
SDM suggests VMXON should be called before VMPTRLD, and VMXOFF
should be called after doing VMCLEAR.

Therefore in vmm coexistence case, we should firstly call VMXON
before any VMCS operation, and then call VMXOFF after the
operation is done.

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:35:43 +03:00
Dongxiao Xu b923e62e4d KVM: VMX: VMCLEAR/VMPTRLD usage changes
Originally VMCLEAR/VMPTRLD is called on vcpu migration. To
support hosted VMM coexistance, VMCLEAR is executed on vcpu
schedule out, and VMPTRLD is executed on vcpu schedule in.
This could also eliminate the IPI when doing VMCLEAR.

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:35:42 +03:00
Dongxiao Xu 92fe13be74 KVM: VMX: Some minor changes to code structure
Do some preparations for vmm coexistence support.

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:35:42 +03:00
Dongxiao Xu 7725b89414 KVM: VMX: Define new functions to wrapper direct call of asm code
Define vmcs_load() and kvm_cpu_vmxon() to avoid direct call of asm
code. Also move VMXE bit operation out of kvm_cpu_vmxoff().

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:35:41 +03:00
Gleb Natapov 6d77dbfc88 KVM: inject #UD if instruction emulation fails and exit to userspace
Do not kill VM when instruction emulation fails. Inject #UD and report
failure to userspace instead. Userspace may choose to reenter guest if
vcpu is in userspace (cpl == 3) in which case guest OS will kill
offending process and continue running.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-08-01 10:35:40 +03:00
Avi Kivity 1c11e71357 KVM: VMX: Avoid writing HOST_CR0 every entry
cr0.ts may change between entries, so we copy cr0 to HOST_CR0 before each
entry.  That is slow, so instead, set HOST_CR0 to have TS set unconditionally
(which is a safe value), and issue a clts() just before exiting vcpu context
if the task indeed owns the fpu.

Saves ~50 cycles/exit.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:28 +03:00
Avi Kivity c332c83ae7 KVM: VMX: Simplify vmx_get_nmi_mask()
!! is not needed due to the cast to bool.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:27 +03:00
Brian Gerst 8c06585d64 x86: Remove redundant K6 MSRs
MSR_K6_EFER is unused, and MSR_K6_STAR is redundant with MSR_STAR.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1279371808-24804-1-git-send-email-brgerst@gmail.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-07-21 21:23:05 -07:00
Avi Kivity da38f43859 KVM: VMX: Fix host MSR_KERNEL_GS_BASE corruption
enter_lmode() and exit_lmode() modify the guest's EFER.LMA before calling
vmx_set_efer().  However, the latter function depends on the value of EFER.LMA
to determine whether MSR_KERNEL_GS_BASE needs reloading, via
vmx_load_host_state().  With EFER.LMA changing under its feet, it took the
wrong choice and corrupted userspace's %gs.

This causes 32-on-64 host userspace to fault.

Fix not touching EFER.LMA; instead ask vmx_set_efer() to change it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-07-06 11:41:31 +03:00
Linus Torvalds 98edb6ca41 Merge branch 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (269 commits)
  KVM: x86: Add missing locking to arch specific vcpu ioctls
  KVM: PPC: Add missing vcpu_load()/vcpu_put() in vcpu ioctls
  KVM: MMU: Segregate shadow pages with different cr0.wp
  KVM: x86: Check LMA bit before set_efer
  KVM: Don't allow lmsw to clear cr0.pe
  KVM: Add cpuid.txt file
  KVM: x86: Tell the guest we'll warn it about tsc stability
  x86, paravirt: don't compute pvclock adjustments if we trust the tsc
  x86: KVM guest: Try using new kvm clock msrs
  KVM: x86: export paravirtual cpuid flags in KVM_GET_SUPPORTED_CPUID
  KVM: x86: add new KVMCLOCK cpuid feature
  KVM: x86: change msr numbers for kvmclock
  x86, paravirt: Add a global synchronization point for pvclock
  x86, paravirt: Enable pvclock flags in vcpu_time_info structure
  KVM: x86: Inject #GP with the right rip on efer writes
  KVM: SVM: Don't allow nested guest to VMMCALL into host
  KVM: x86: Fix exception reinjection forced to true
  KVM: Fix wallclock version writing race
  KVM: MMU: Don't read pdptrs with mmu spinlock held in mmu_alloc_roots
  KVM: VMX: enable VMXON check with SMX enabled (Intel TXT)
  ...
2010-05-21 17:16:21 -07:00
Shane Wang cafd66595d KVM: VMX: enable VMXON check with SMX enabled (Intel TXT)
Per document, for feature control MSR:

  Bit 1 enables VMXON in SMX operation. If the bit is clear, execution
        of VMXON in SMX operation causes a general-protection exception.
  Bit 2 enables VMXON outside SMX operation. If the bit is clear, execution
        of VMXON outside SMX operation causes a general-protection exception.

This patch is to enable this kind of check with SMX for VMXON in KVM.

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-19 11:36:34 +03:00
Avi Kivity 84ad33ef5d KVM: VMX: Atomically switch efer if EPT && !EFER.NX
When EPT is enabled, we cannot emulate EFER.NX=0 through the shadow page
tables.  This causes accesses through ptes with bit 63 set to succeed instead
of failing a reserved bit check.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-19 11:36:32 +03:00
Avi Kivity 61d2ef2ce3 KVM: VMX: Add facility to atomically switch MSRs on guest entry/exit
Some guest msr values cannot be used on the host (for example. EFER.NX=0),
so we need to switch them atomically during guest entry or exit.

Add a facility to program the vmx msr autoload registers accordingly.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-19 11:36:31 +03:00
Avi Kivity 0ee75bead8 KVM: Let vcpu structure alignment be determined at runtime
vmx and svm vcpus have different contents and therefore may have different
alignmment requirements.  Let each specify its required alignment.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-19 11:36:29 +03:00
Linus Torvalds 4d7b4ac22f Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (311 commits)
  perf tools: Add mode to build without newt support
  perf symbols: symbol inconsistency message should be done only at verbose=1
  perf tui: Add explicit -lslang option
  perf options: Type check all the remaining OPT_ variants
  perf options: Type check OPT_BOOLEAN and fix the offenders
  perf options: Check v type in OPT_U?INTEGER
  perf options: Introduce OPT_UINTEGER
  perf tui: Add workaround for slang < 2.1.4
  perf record: Fix bug mismatch with -c option definition
  perf options: Introduce OPT_U64
  perf tui: Add help window to show key associations
  perf tui: Make <- exit menus too
  perf newt: Add single key shortcuts for zoom into DSO and threads
  perf newt: Exit browser unconditionally when CTRL+C, q or Q is pressed
  perf newt: Fix the 'A'/'a' shortcut for annotate
  perf newt: Make <- exit the ui_browser
  x86, perf: P4 PMU - fix counters management logic
  perf newt: Make <- zoom out filters
  perf report: Report number of events, not samples
  perf hist: Clarify events_stats fields usage
  ...

Fix up trivial conflicts in kernel/fork.c and tools/perf/builtin-record.c
2010-05-18 08:19:03 -07:00
Joerg Roedel ce7ddec4bb KVM: x86: Allow marking an exception as reinjected
This patch adds logic to kvm/x86 which allows to mark an
injected exception as reinjected. This allows to remove an
ugly hack from svm_complete_interrupts that prevented
exceptions from being reinjected at all in the nested case.
The hack was necessary because an reinjected exception into
the nested guest could cause a nested vmexit emulation. But
reinjected exceptions must not intercept. The downside of
the hack is that a exception that in injected could get
lost.
This patch fixes the problem and puts the code for it into
generic x86 files because. Nested-VMX will likely have the
same problem and could reuse the code.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:26 +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
Lai Jiangshan cdbecfc398 KVM: VMX: free vpid when fail to create vcpu
Fix bug of the exception path, free allocated vpid when fail
to create vcpu.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:19:10 +03:00
Lai Jiangshan 90d83dc3d4 KVM: use the correct RCU API for PROVE_RCU=y
The RCU/SRCU API have already changed for proving RCU usage.

I got the following dmesg when PROVE_RCU=y because we used incorrect API.
This patch coverts rcu_deference() to srcu_dereference() or family API.

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
arch/x86/kvm/mmu.c:3020 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
2 locks held by qemu-system-x86/8550:
 #0:  (&kvm->slots_lock){+.+.+.}, at: [<ffffffffa011a6ac>] kvm_set_memory_region+0x29/0x50 [kvm]
 #1:  (&(&kvm->mmu_lock)->rlock){+.+...}, at: [<ffffffffa012262d>] kvm_arch_commit_memory_region+0xa6/0xe2 [kvm]

stack backtrace:
Pid: 8550, comm: qemu-system-x86 Not tainted 2.6.34-rc4-tip-01028-g939eab1 #27
Call Trace:
 [<ffffffff8106c59e>] lockdep_rcu_dereference+0xaa/0xb3
 [<ffffffffa012f6c1>] kvm_mmu_calculate_mmu_pages+0x44/0x7d [kvm]
 [<ffffffffa012263e>] kvm_arch_commit_memory_region+0xb7/0xe2 [kvm]
 [<ffffffffa011a5d7>] __kvm_set_memory_region+0x636/0x6e2 [kvm]
 [<ffffffffa011a6ba>] kvm_set_memory_region+0x37/0x50 [kvm]
 [<ffffffffa015e956>] vmx_set_tss_addr+0x46/0x5a [kvm_intel]
 [<ffffffffa0126592>] kvm_arch_vm_ioctl+0x17a/0xcf8 [kvm]
 [<ffffffff810a8692>] ? unlock_page+0x27/0x2c
 [<ffffffff810bf879>] ? __do_fault+0x3a9/0x3e1
 [<ffffffffa011b12f>] kvm_vm_ioctl+0x364/0x38d [kvm]
 [<ffffffff81060cfa>] ? up_read+0x23/0x3d
 [<ffffffff810f3587>] vfs_ioctl+0x32/0xa6
 [<ffffffff810f3b19>] do_vfs_ioctl+0x495/0x4db
 [<ffffffff810e6b2f>] ? fget_light+0xc2/0x241
 [<ffffffff810e416c>] ? do_sys_open+0x104/0x116
 [<ffffffff81382d6d>] ? retint_swapgs+0xe/0x13
 [<ffffffff810f3ba6>] sys_ioctl+0x47/0x6a
 [<ffffffff810021db>] system_call_fastpath+0x16/0x1b

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:18:01 +03:00
Avi Kivity 9beeaa2d68 Merge branch 'perf'
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:17:58 +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
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
Gui Jianfeng 3129994458 KVM: VMX: change to use bool return values
Make use of bool as return values, and remove some useless
bool value converting. Thanks Avi to point this out.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:51 +03:00
Wei Yongjun ec68798c8f KVM: x86: Use native_store_idt() instead of kvm_get_idt()
This patch use generic linux function native_store_idt()
instead of kvm_get_idt(), and also removed the useless
function kvm_get_idt().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:28 +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
Jan Kiszka f8c5fae166 KVM: VMX: blocked-by-sti must not defer NMI injections
As the processor may not consider GUEST_INTR_STATE_STI as a reason for
blocking NMI, it could return immediately with EXIT_REASON_NMI_WINDOW
when we asked for it. But as we consider this state as NMI-blocking, we
can run into an endless loop.

Resolve this by allowing NMI injection if just GUEST_INTR_STATE_STI is
active (originally suggested by Gleb). Intel confirmed that this is
safe, the processor will never complain about NMI injection in this
state.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
KVM-Stable-Tag
Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-13 01:31:37 -03:00
Gleb Natapov 2d49ec72d3 KVM: move segment_base() into vmx.c
segment_base() is used only by vmx so move it there.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:39 +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
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
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
Ingo Molnar 70bce3ba77 Merge branch 'linus' into perf/core
Merge reason: merge the latest fixes, update to latest -rc.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-23 11:10:30 +02:00
Avi Kivity 78ac8b47c5 KVM: VMX: Save/restore rflags.vm correctly in real mode
Currently we set eflags.vm unconditionally when entering real mode emulation
through virtual-8086 mode, and clear it unconditionally when we enter protected
mode.  The means that the following sequence

  KVM_SET_REGS  (rflags.vm=1)
  KVM_SET_SREGS (cr0.pe=1)

Ends up with rflags.vm clear due to KVM_SET_SREGS triggering enter_pmode().

Fix by shadowing rflags.vm (and rflags.iopl) correctly while in real mode:
reads and writes to those bits access a shadow register instead of the actual
register.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-04-20 12:59:31 +03:00
Zhang, Yanmin ff9d07a0e7 KVM: Implement perf callbacks for guest sampling
Below patch implements the perf_guest_info_callbacks on kvm.

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-19 12:36:50 +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
Jan Kiszka c573cd2293 KVM: VMX: Update instruction length on intercepted BP
We intercept #BP while in guest debugging mode. As VM exits due to
intercepted exceptions do not necessarily come with valid
idt_vectoring, we have to update event_exit_inst_len explicitly in such
cases. At least in the absence of migration, this ensures that
re-injections of #BP will find and use the correct instruction length.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: stable@kernel.org (2.6.32, 2.6.33)
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:14 -03:00
Sheng Yang a19a6d1131 KVM: VMX: Rename VMX_EPT_IGMT_BIT to VMX_EPT_IPAT_BIT
Following the new SDM. Now the bit is named "Ignore PAT memory type".

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:09 -03:00
Julia Lawall c45b4fd416 KVM: VMX: Remove redundant test in vmx_set_efer()
msr was tested above, so the second test is not needed.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
expression *x;
expression e;
identifier l;
@@

if (x == NULL || ...) {
    ... when forall
    return ...; }
... when != goto l;
    when != x = e
    when != &x
*x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:07 -03:00
Avi Kivity ebcbab4c03 KVM: VMX: Wire up .fpu_activate() callback
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:07 -03:00
Gui Jianfeng 6d3e435e70 KVM: VMX: Remove redundant check in vm_need_virtualize_apic_accesses()
flexpriority_enabled implies cpu_has_vmx_virtualize_apic_accesses() returning
true, so we don't need this check here.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:06 -03:00
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 81231c698a KVM: VMX: Pass cr0.mp through to the guest when the fpu is active
When cr0.mp is clear, the guest doesn't expect a #NM in response to
a WAIT instruction.  Because we always keep cr0.mp set, it will get
a #NM, and potentially be confused.

Fix by keeping cr0.mp set only when the fpu is inactive, and passing
it through when inactive.

Reported-by: Lorenzo Martignoni <martignlo@gmail.com>
Analyzed-by: Gleb Natapov <gleb@redhat.com>
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 3eeb3288bc KVM: Add a helper for checking if the guest is in protected mode
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 fd7373cce7 KVM: VMX: Clean up DR6 emulation
As we trap all debug register accesses, we do not need to switch real
DR6 at all. Clean up update_exception_bitmap at this chance, too.

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 138ac8d88f KVM: VMX: Fix emulation of DR4 and DR5
Make sure DR4 and DR5 are aliased to DR6 and DR7, respectively, if
CR4.DE is not set.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -03:00
Jan Kiszka f248341529 KVM: VMX: Fix exceptions of mov to dr
Injecting GP without an error code is a bad idea (causes unhandled guest
exits). Moreover, we must not skip the instruction if we injected an
exception.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -03:00
Sheng Yang 7062dcaa36 KVM: VMX: Remove emulation failure report
As Avi noted:

>There are two problems with the kernel failure report.  First, it
>doesn't report enough data - registers, surrounding instructions, etc.
>that are needed to explain what is going on.  Second, it can flood
>dmesg, which is a pretty bad thing to do.

So we remove the emulation failure report in handle_invalid_guest_state(),
and would inspected the guest using userspace tool in the future.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -03:00
Avi Kivity edcafe3c5a KVM: VMX: Give the guest ownership of cr0.ts when the fpu is active
If the guest fpu is loaded, there is nothing interesing about cr0.ts; let
the guest play with it as it will.  This makes context switches between fpu
intensive guest processes faster, as we won't trap the clts and cr0 write
instructions.

[marcelo: fix cr0 read shadow update on fpu deactivation; kills F8 install]

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity 02daab21d9 KVM: Lazify fpu activation and deactivation
Defer fpu deactivation as much as possible - if the guest fpu is loaded, keep
it loaded until the next heavyweight exit (where we are forced to unload it).
This reduces unnecessary exits.

We also defer fpu activation on clts; while clts signals the intent to use the
fpu, we can't be sure the guest will actually use it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity e8467fda83 KVM: VMX: Allow the guest to own some cr0 bits
We will use this later to give the guest ownership of cr0.ts.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity 4d4ec08745 KVM: Replace read accesses of vcpu->arch.cr0 by an accessor
Since we'd like to allow the guest to own a few bits of cr0 at times, we need
to know when we access those bits.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity a1f83a74fe KVM: VMX: trace clts and lmsw instructions as cr accesses
clts writes cr0.ts; lmsw writes cr0[0:15] - record that in ftrace.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Sheng Yang 878403b788 KVM: VMX: Enable EPT 1GB page support
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:46 -03:00
Sheng Yang 17cc393596 KVM: x86: Rename gb_page_enable() to get_lpage_level() in kvm_x86_ops
Then the callback can provide the maximum supported large page level, which
is more flexible.

Also move the gb page support into x86_64 specific.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:46 -03:00
Avi Kivity f4c9e87c83 KVM: Fill out ftrace exit reason strings
Some exit reasons missed their strings; fill out the table.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:45 -03:00
Marcelo Tosatti 79fac95ecf KVM: convert slots_lock to a mutex
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:45 -03:00
Marcelo Tosatti f656ce0185 KVM: switch vcpu context to use SRCU
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:45 -03:00
Marcelo Tosatti bc6678a33d KVM: introduce kvm->srcu and convert kvm_set_memory_region to SRCU update
Use two steps for memslot deletion: mark the slot invalid (which stops
instantiation of new shadow pages for that slot, but allows destruction),
then instantiate the new empty slot.

Also simplifies kvm_handle_hva locking.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:44 -03:00
Marcelo Tosatti 46a26bf557 KVM: modify memslots layout in struct kvm
Have a pointer to an allocated region inside struct kvm.

[alex: fix ppc book 3s]

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:43 -03:00
Sheng Yang 4e47c7a6d7 KVM: VMX: Add instruction rdtscp support for guest
Before enabling, execution of "rdtscp" in guest would result in #UD.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Sheng Yang 0e85188049 KVM: Add cpuid_update() callback to kvm_x86_ops
Sometime, we need to adjust some state in order to reflect guest CPUID
setting, e.g. if we don't expose rdtscp to guest, we won't want to enable
it on hardware. cpuid_update() is introduced for this purpose.

Also export kvm_find_cpuid_entry() for later use.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Sheng Yang 8a7e3f01e6 KVM: VMX: Remove redundant variable
It's no longer necessary.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Avi Kivity bc23008b61 KVM: VMX: Fold ept_update_paging_mode_cr4() into its caller
ept_update_paging_mode_cr4() accesses vcpu->arch.cr4 directly, which usually
needs to be accessed via kvm_read_cr4().  In this case, we can't, since cr4
is in the process of being updated.  Instead of adding inane comments, fold
the function into its caller (vmx_set_cr4), so it can use the not-yet-committed
cr4 directly.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Avi Kivity ce03e4f21a KVM: VMX: When using ept, allow the guest to own cr4.pge
We make no use of cr4.pge if ept is enabled, but the guest does (to flush
global mappings, as with vmap()), so give the guest ownership of this bit.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity 4c38609ac5 KVM: VMX: Make guest cr4 mask more conservative
Instead of specifying the bits which we want to trap on, specify the bits
which we allow the guest to change transparently.  This is safer wrt future
changes to cr4.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity fc78f51938 KVM: Add accessor for reading cr4 (or some bits of cr4)
Some bits of cr4 can be owned by the guest on vmx, so when we read them,
we copy them to the vcpu structure.  In preparation for making the set of
guest-owned bits dynamic, use helpers to access these bits so we don't need
to know where the bit resides.

No changes to svm since all bits are host-owned there.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity cdc0e24456 KVM: VMX: Move some cr[04] related constants to vmx.c
They have no place in common code.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Sheng Yang 59708670b6 KVM: VMX: Trap and invalid MWAIT/MONITOR instruction
We don't support these instructions, but guest can execute them even if the
feature('monitor') haven't been exposed in CPUID. So we would trap and inject
a #UD if guest try this way.

Cc: stable@kernel.org
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity d5696725b2 KVM: VMX: Fix comparison of guest efer with stale host value
update_transition_efer() masks out some efer bits when deciding whether
to switch the msr during guest entry; for example, NX is emulated using the
mmu so we don't need to disable it, and LMA/LME are handled by the hardware.

However, with shared msrs, the comparison is made against a stale value;
at the time of the guest switch we may be running with another guest's efer.

Fix by deferring the mask/compare to the actual point of guest entry.

Noted by Marcelo.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:34:20 +02:00