Commit Graph

576 Commits

Author SHA1 Message Date
Gleb Natapov
5951c44237 KVM: x86 emulator: add get_cached_segment_base() callback to x86_emulate_ops
On VMX it is expensive to call get_cached_descriptor() just to get segment
base since multiple vmcs_reads are done instead of only one. Introduce
new call back get_cached_segment_base() for efficiency.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:31 +03:00
Gleb Natapov
3fb1b5dbd3 KVM: x86 emulator: add (set|get)_msr callbacks to x86_emulate_ops
Add (set|get)_msr callbacks to x86_emulate_ops instead of calling
them directly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:30 +03:00
Gleb Natapov
35aa5375d4 KVM: x86 emulator: add (set|get)_dr callbacks to x86_emulate_ops
Add (set|get)_dr callbacks to x86_emulate_ops instead of calling
them directly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:30 +03:00
Gleb Natapov
414e6277fd KVM: x86 emulator: handle "far address" source operand
ljmp/lcall instruction operand contains address and segment.
It can be 10 bytes long. Currently we decode it as two different
operands. Fix it by introducing new kind of operand that can hold
entire far address.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:30 +03:00
Gleb Natapov
b8a98945ea KVM: x86 emulator: cleanup nop emulation
Make it more explicit what we are checking for.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:29 +03:00
Gleb Natapov
f0c13ef1a8 KVM: x86 emulator: cleanup xchg emulation
Dst operand is already initialized during decoding stage. No need to
reinitialize.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:29 +03:00
Gleb Natapov
054fe9f6e3 KVM: x86 emulator: fix Move r/m16 to segment register decoding
This instruction does not need generic decoding for its dst operand.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:28 +03:00
Gleb Natapov
9de4157367 KVM: x86 emulator: introduce read cache
Introduce read cache which is needed for instruction that require more
then one exit to userspace. After returning from userspace the instruction
will be re-executed with cached read value.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-08-01 10:35:28 +03:00
Gleb Natapov
19d0443726 KVM: fix emulator_task_switch() return value.
emulator_task_switch() should return -1 for failure and 0 for success to
the caller, just like x86_emulate_insn() does.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:49 +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
Jan Kiszka
0760d44868 KVM: x86: Terminate early if task_switch_16/32 failed
Stop the switch immediately if task_switch_16/32 returned an error. Only
if that step succeeded, the switch should actually take place and update
any register states.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:44 +03:00
Avi Kivity
2fb53ad811 KVM: x86 emulator: Don't overwrite decode cache
Currently if we an instruction spans a page boundary, when we fetch the
second half we overwrite the first half.  This prevents us from tracing
the full instruction opcodes.

Fix by appending the second half to the first.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:33 +03:00
Gleb Natapov
de3e6480f7 KVM: x86 emulator: fix unlocked CMPXCHG8B emulation
When CMPXCHG8B is executed without LOCK prefix it is racy. Preserve this
behaviour in emulator too.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:38 +03:00
Gleb Natapov
6550e1f165 KVM: x86 emulator: add decoding of CMPXCHG8B dst operand
Decode CMPXCHG8B destination operand in decoding stage. Fixes regression
introduced by "If LOCK prefix is used dest arg should be memory" commit.
This commit relies on dst operand be decoded at the beginning of an
instruction emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:37 +03:00
Gleb Natapov
482ac18ae2 KVM: x86 emulator: commit rflags as part of registers commit
Make sure that rflags is committed only after successful instruction
emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:35 +03:00
Gleb Natapov
7b262e90fc KVM: x86 emulator: introduce pio in string read ahead.
To optimize "rep ins" instruction do IO in big chunks ahead of time
instead of doing it only when required during instruction emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:31 +03:00
Gleb Natapov
5cd21917da KVM: x86 emulator: restart string instruction without going back to a guest.
Currently when string instruction is only partially complete we go back
to a guest mode, guest tries to reexecute instruction and exits again
and at this point emulation continues. Avoid all of this by restarting
instruction without going back to a guest mode, but return to a guest
mode each 1024 iterations to allow interrupt injection. Pending
exception causes immediate guest entry too.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:29 +03:00
Gleb Natapov
cb404fe089 KVM: x86 emulator: remove saved_eip
c->eip is never written back in case of emulation failure, so no need to
set it to old value.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:28 +03:00
Gleb Natapov
7972995b0c KVM: x86 emulator: Move string pio emulation into emulator.c
Currently emulation is done outside of emulator so things like doing
ins/outs to/from mmio are broken it also makes it hard (if not impossible)
to implement single stepping in the future. The implementation in this
patch is not efficient since it exits to userspace for each IO while
previous implementation did 'ins' in batches. Further patch that
implements pio in string read ahead address this problem.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:26 +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
Gleb Natapov
d9271123a4 KVM: x86 emulator: during rep emulation decrement ECX only if emulation succeeded
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:23 +03:00
Gleb Natapov
a682e35449 KVM: x86 emulator: add decoding of X,Y parameters from Intel SDM
Add decoding of X,Y parameters from Intel SDM which are used by string
instruction to specify source and destination. Use this new decoding
to implement movs, cmps, stos, lods in a generic way.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:21 +03:00
Gleb Natapov
69f55cb11e KVM: x86 emulator: populate OP_MEM operand during decoding.
All struct operand fields are initialized during decoding for all
operand types except OP_MEM, but there is no reason for that. Move
OP_MEM operand initialization into decoding stage for consistency.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:20 +03:00
Gleb Natapov
ceffb45972 KVM: Use task switch from emulator.c
Remove old task switch code from x86.c

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:18 +03:00
Gleb Natapov
2e873022f5 KVM: x86 emulator: Use load_segment_descriptor() instead of kvm_load_segment_descriptor()
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:17 +03:00
Gleb Natapov
38ba30ba51 KVM: x86 emulator: Emulate task switch in emulator.c
Implement emulation of 16/32 bit task switch in emulator.c

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:15 +03:00
Gleb Natapov
aca06a8307 KVM: x86 emulator: cleanup grp3 return value
When x86_emulate_insn() does not know how to emulate instruction it
exits via cannot_emulate label in all cases except when emulating
grp3. Fix that.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:12 +03:00
Gleb Natapov
a41ffb7540 KVM: x86 emulator: If LOCK prefix is used dest arg should be memory.
If LOCK prefix is used dest arg should be memory, otherwise instruction
should generate #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:11 +03:00
Gleb Natapov
fd5253658b KVM: x86 emulator: do not call writeback if msr access fails.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:09 +03:00
Gleb Natapov
2e901c4cf4 KVM: x86 emulator: fix return values of syscall/sysenter/sysexit emulations
Return X86EMUL_PROPAGATE_FAULT is fault was injected. Also inject #UD
for those instruction when appropriate.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:08 +03:00
Gleb Natapov
1e470be5a1 KVM: x86 emulator: fix mov dr to inject #UD when needed.
If CR4.DE=1 access to registers DR4/DR5 cause #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:06 +03:00
Gleb Natapov
6aebfa6ea7 KVM: x86 emulator: inject #UD on access to non-existing CR
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:05 +03:00
Gleb Natapov
ab8557b2b3 KVM: x86 emulator: 0f (20|21|22|23) ignore mod bits.
Resent spec says that for 0f (20|21|22|23) the 2 bits in the mod field
are ignored. Interestingly enough older spec says that 11 is only valid
encoding.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:03 +03:00
Gleb Natapov
6e1e5ffee8 KVM: x86 emulator: fix 0f 01 /5 emulation
It is undefined and should generate #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:02 +03:00
Gleb Natapov
5e3ae6c540 KVM: x86 emulator: fix mov r/m, sreg emulation.
mov r/m, sreg generates #UD ins sreg is incorrect.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:00 +03:00
Gleb Natapov
063db061b9 KVM: Provide current eip as part of emulator context.
Eliminate the need to call back into KVM to get it from emulator.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:59 +03:00
Gleb Natapov
9c5372445c KVM: Provide x86_emulate_ctxt callback to get current cpl
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:57 +03:00
Gleb Natapov
93a152be5a KVM: remove realmode_lmsw function.
Use (get|set)_cr callback to emulate lmsw inside emulator.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:56 +03:00
Gleb Natapov
52a4661737 KVM: Provide callback to get/set control registers in emulator ops.
Use this callback instead of directly call kvm function. Also rename
realmode_(set|get)_cr to emulator_(set|get)_cr since function has nothing
to do with real mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:54 +03:00
Gleb Natapov
49c6799a2c KVM: Remove pointer to rflags from realmode_set_cr parameters.
Mov reg, cr instruction doesn't change flags in any meaningful way, so
no need to update rflags after instruction execution.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:50 +03:00
Gleb Natapov
af5b4f7ff7 KVM: x86 emulator: check return value against correct define
Check return value against correct define instead of open code
the value.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:48 +03:00
Gleb Natapov
c73e197bc5 KVM: x86 emulator: fix RCX access during rep emulation
During rep emulation access length to RCX depends on current address
mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:47 +03:00
Gleb Natapov
d6d367d678 KVM: x86 emulator: Fix DstAcc decoding.
Set correct operation length. Add RAX (64bit) handling.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:45 +03:00
Gleb Natapov
835e6b8047 KVM: x86 emulator mark VMMCALL and LMSW as privileged
LMSW is present in both group tables. It was marked privileged only in
one of them. Intel analog of VMMCALL is already marked privileged.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:18 +03:00
Gleb Natapov
ea79849d4c KVM: x86 emulator: Implement jmp far opcode ff/5
Implement jmp far opcode ff/5. It is used by multiboot loader.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:45 +03:00
Gleb Natapov
e35b7b9c9e KVM: x86 emulator: Add decoding of 16bit second in memory argument
Add decoding of Ep type of argument used by callf/jmpf.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:42 +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
Takuya Yoshikawa
0e4176a15f KVM: x86 emulator: Fix x86_emulate_insn() not to use the variable rc for non-X86EMUL values
This patch makes non-X86EMUL_* family functions not to use
the variable rc.

Be sure that this changes nothing but makes the purpose of
the variable rc clearer.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:50 +03:00
Takuya Yoshikawa
1b30eaa846 KVM: x86 emulator: X86EMUL macro replacements: x86_emulate_insn() and its helpers
This patch just replaces integer values used inside
x86_emulate_insn() and its helper functions to X86EMUL_*.

The purpose of this is to make it clear what will happen
when the variable rc is compared to X86EMUL_* at the end
of x86_emulate_insn().

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:46 +03:00
Takuya Yoshikawa
3e2815e9fa KVM: x86 emulator: X86EMUL macro replacements: from do_fetch_insn_byte() to x86_decode_insn()
This patch just replaces the integer values used inside x86's
decode functions to X86EMUL_*.

By this patch, it becomes clearer that we are using X86EMUL_*
value propagated from ops->read_std() in do_fetch_insn_byte().

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:43 +03:00
Gleb Natapov
1161624f15 KVM: inject #UD in 64bit mode from instruction that are not valid there
Some instruction are obsolete in a long mode. Inject #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:40 +03:00
Takuya Yoshikawa
e54cfa97a9 KVM: Fix emulate_sys[call, enter, exit]()'s fault handling
This patch fixes emulate_syscall(), emulate_sysenter() and
emulate_sysexit() to handle injected faults properly.

Even though original code injects faults in these functions,
we cannot handle these unless we use the different return
value from the UNHANDLEABLE case. So this patch use X86EMUL_*
codes instead of -1 and 0 and makes x86_emulate_insn() to
handle these propagated faults.

Be sure that, in x86_emulate_insn(), goto cannot_emulate and
goto done with rc equals X86EMUL_UNHANDLEABLE have same effect.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:14 -03:00
Gleb Natapov
c697518a86 KVM: Fix segment descriptor loading
Add proper error and permission checking. This patch also change task
switching code to load segment selectors before segment descriptors, like
SDM requires, otherwise permission checking during segment descriptor
loading will be incorrect.

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 12:36:14 -03:00
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