Commit Graph

23 Commits

Author SHA1 Message Date
Gleb Natapov 8b9f44140b KVM: x86 emulator: Forbid modifying CS segment register by mov instruction
Inject #UD if guest attempts to do so. This is in accordance to Intel
SDM.

Cc: stable@kernel.org (2.6.33, 2.6.32)
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:13 -03:00
Gleb Natapov e424e19183 KVM: x86 emulator: disallow opcode 82 in 64-bit mode
Instructions with opcode 82 are not valid in 64 bit mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:12 -03:00
Wei Yongjun 1d327eac3c KVM: x86 emulator: code style cleanup
Just remove redundant semicolon.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:12 -03:00
Gleb Natapov d380a5e402 KVM: x86 emulator: Add LOCK prefix validity checking
Instructions which are not allowed to have LOCK prefix should
generate #UD if one is used.

[avi: fold opcode 82 fix from another patch]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov e92805ac12 KVM: x86 emulator: Check CPL level during privilege instruction emulation
Add CPL checking in case emulator is tricked into emulating
privilege instruction from userspace.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov d4c6a1549c KVM: x86 emulator: Fix popf emulation
POPF behaves differently depending on current CPU mode. Emulate correct
logic to prevent guest from changing flags that it can't change otherwise.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov f850e2e603 KVM: x86 emulator: Check IOPL level during io instruction emulation
Make emulator check that vcpu is allowed to execute IN, INS, OUT,
OUTS, CLI, STI.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov 1871c6020d KVM: x86 emulator: fix memory access during x86 emulation
Currently when x86 emulator needs to access memory, page walk is done with
broadest permission possible, so if emulated instruction was executed
by userspace process it can still access kernel memory. Fix that by
providing correct memory access to page walker during emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov a004475567 KVM: x86 emulator: Add Virtual-8086 mode of emulation
For some instructions CPU behaves differently for real-mode and
virtual 8086. Let emulator know which mode cpu is in, so it will
not poke into vcpu state directly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov 60a29d4ea4 KVM: x86 emulator: Add group9 instruction decoding
Use groups mechanism to decode 0F C7 instructions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:10 -03:00
Gleb Natapov 2db2c2eb62 KVM: x86 emulator: Add group8 instruction decoding
Use groups mechanism to decode 0F BA instructions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:10 -03:00
Avi Kivity 836a1b3c34 KVM: Move cr0/cr4/efer related helpers to x86.h
They have more general scope than the mmu.

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
Takuya Yoshikawa b60d513c32 KVM: x86: Use macros for x86_emulate_ops to avoid future mistakes
The return values from x86_emulate_ops are defined
in kvm_emulate.h as macros X86EMUL_*.

But in emulate.c, we are comparing the return values
from these ops with 0 to check if they're X86EMUL_CONTINUE
or not: X86EMUL_CONTINUE is defined as 0 now.

To avoid possible mistakes in the future, this patch
substitutes "X86EMUL_CONTINUE" for "0" that are being
compared with the return values from x86_emulate_ops.

  We think that there are more places we should use these
  macros, but the meanings of rc values in x86_emulate_insn()
  were not so clear at a glance. If we use proper macros in
  this function, we would be able to follow the flow of each
  emulation more easily and, maybe, more securely.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -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 eb3c79e64a KVM: x86 emulator: limit instructions to 15 bytes
While we are never normally passed an instruction that exceeds 15 bytes,
smp games can cause us to attempt to interpret one, which will cause
large latencies in non-preempt hosts.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:25 +02:00
Mohammed Gamal abcf14b560 KVM: x86 emulator: Add pusha and popa instructions
This adds pusha and popa instructions (opcodes 0x60-0x61), this enables booting
MINIX with invalid guest state emulation on.

[marcelo: remove unused variable]

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:09 +02:00
Mohammed Gamal 94677e61fd KVM: x86 emulator: Add missing decoder flags for 'or' instructions
Add missing decoder flags for or instructions (0xc-0xd).

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:09 +02:00
Avi Kivity 851ba6922a KVM: Don't pass kvm_run arguments
They're just copies of vcpu->run, which is readily accessible.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:06 +02:00
Mohammed Gamal d8769fedd4 KVM: x86 emulator: Introduce No64 decode option
Introduces a new decode option "No64", which is used for instructions that are
invalid in long mode.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:05 +02:00
Mohammed Gamal 0934ac9d13 KVM: x86 emulator: Add 'push/pop sreg' instructions
[avi: avoid buffer overflow]

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:05 +02:00
Mohammed Gamal 7bdb588827 KVM: x86 emulator: Add adc and sbb missing decoder flags
Add missing decoder flags for adc and sbb instructions
(opcodes 0x14-0x15, 0x1c-0x1d)

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:51 +03:00
Avi Kivity 56e8231841 KVM: Rename x86_emulate.c to emulate.c
We're in arch/x86, what could we possibly be emulating?

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:45 +03:00