Commit graph

402 commits

Author SHA1 Message Date
Gleb Natapov
9d1b39a967 KVM: emulator: make x86 emulation modes enum instead of defines
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-06 18:07:01 +03:00
Mathias Krause
0225fb509d KVM: x86 emulator: constify emulate_ops
We never change emulate_ops[] at runtime so it should be r/o.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-05 12:41:48 +03:00
Mathias Krause
fd0a0d8208 KVM: x86 emulator: mark opcode tables const
The opcode tables never change at runtime, therefor mark them const.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-05 12:41:28 +03:00
Mathias Krause
89a87c6779 KVM: x86 emulator: use aligned variants of SSE register ops
As the the compiler ensures that the memory operand is always aligned
to a 16 byte memory location, use the aligned variant of MOVDQ for
read_sse_reg() and write_sse_reg().

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-05 12:41:11 +03:00
Avi Kivity
0afbe2f878 KVM: x86 emulator: Fix #GP error code during linearization
We want the segment selector, nor segment number.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-27 20:02:20 -03:00
Avi Kivity
a5625189f6 KVM: x86 emulator: Check segment limits in real mode too
Segment limits are verified in real mode, not just protected mode.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-27 20:02:20 -03:00
Avi Kivity
03ebebeb1f KVM: x86 emulator: Leave segment limit and attributs alone in real mode
When loading a segment in real mode, only the base and selector must
be modified.  The limit needs to be left alone, otherwise big real mode
users will hit a #GP due to limit checking (currently this is suppressed
because we don't check limits in real mode).

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-27 20:02:20 -03:00
Avi Kivity
dd856efafe KVM: x86 emulator: access GPRs on demand
Instead of populating the entire register file, read in registers
as they are accessed, and write back only the modified ones.  This
saves a VMREAD and VMWRITE on Intel (for rsp, since it is not usually
used during emulation), and a two 128-byte copies for the registers.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-27 18:38:55 -03:00
Marcelo Tosatti
c78aa4c4b9 Merge remote-tracking branch 'upstream/master' into queue
Merging critical fixes from upstream required for development.

* upstream/master: (809 commits)
  libata: Add a space to " 2GB ATA Flash Disk" DMA blacklist entry
  Revert "powerpc: Update g5_defconfig"
  powerpc/perf: Use pmc_overflow() to detect rolled back events
  powerpc: Fix VMX in interrupt check in POWER7 copy loops
  powerpc: POWER7 copy_to_user/copy_from_user patch applied twice
  powerpc: Fix personality handling in ppc64_personality()
  powerpc/dma-iommu: Fix IOMMU window check
  powerpc: Remove unnecessary ifdefs
  powerpc/kgdb: Restore current_thread_info properly
  powerpc/kgdb: Bail out of KGDB when we've been triggered
  powerpc/kgdb: Do not set kgdb_single_step on ppc
  powerpc/mpic_msgr: Add missing includes
  powerpc: Fix null pointer deref in perf hardware breakpoints
  powerpc: Fixup whitespace in xmon
  powerpc: Fix xmon dl command for new printk implementation
  xfs: check for possible overflow in xfs_ioc_trim
  xfs: unlock the AGI buffer when looping in xfs_dialloc
  xfs: fix uninitialised variable in xfs_rtbuf_get()
  powerpc/fsl: fix "Failed to mount /dev: No such device" errors
  powerpc/fsl: update defconfigs
  ...

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-26 13:58:41 -03:00
Avi Kivity
5ad105e569 KVM: x86 emulator: use stack size attribute to mask rsp in stack ops
The sub-register used to access the stack (sp, esp, or rsp) is not
determined by the address size attribute like other memory references,
but by the stack segment's B bit (if not in x86_64 mode).

Fix by using the existing stack_mask() to figure out the correct mask.

This long-existing bug was exposed by a combination of a27685c33a
(emulate invalid guest state by default), which causes many more
instructions to be emulated, and a seabios change (possibly a bug) which
causes the high 16 bits of esp to become polluted across calls to real
mode software interrupts.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-22 18:54:26 -03:00
Gleb Natapov
99245b507d KVM: x86 emulator: drop unneeded call to get_segment()
setup_syscalls_segments() calls get_segment() and than overwrites all
but one of the structure fields and this one should also be overwritten
anyway, so we can drop call to get_segment() and avoid a couple of vmreads
on vmx. Also drop zeroing ss/cs structures since most of the fields are
set anyway. Just set those that were not set explicitly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-26 12:21:29 +03:00
Xiao Guangrong
f23b070e66 KVM: x86 emulator: simplify read_emulated
No need split mmio read region into 8-bits pieces since we do it in
emulator_read_write_onepage

Changelog:
  Add a WARN_ON to check read-cache overflow

Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-26 12:10:58 +03:00
Guo Chao
fc0586807d KVM: x86: Fix typos in emulate.c
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-07-20 15:26:59 -03:00
Avi Kivity
8089000616 KVM: x86 emulator: implement LTR
Opcode 0F 00 /3.  Encountered during Windows XP secondary processor bringup.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:05 +03:00
Avi Kivity
869be99c75 KVM: x86 emulator: make loading TR set the busy bit
Guest software doesn't actually depend on it, but vmx will refuse us
entry if we don't.  Set the bit in both the cached segment and memory,
just to be nice.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:05 +03:00
Avi Kivity
e919464b53 KVM: x86 emulator: make read_segment_descriptor() return the address
Some operations want to modify the descriptor later on, so save the
address for future use.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:04 +03:00
Avi Kivity
a14e579f22 KVM: x86 emulator: emulate LLDT
Opcode 0F 00 /2. Used by isolinux durign the protected mode transition.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:04 +03:00
Avi Kivity
9299836e63 KVM: x86 emulator: emulate BSWAP
Opcodes 0F C8 - 0F CF.

Used by the SeaBIOS cdrom code (though not in big real mode).

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:04 +03:00
Avi Kivity
612e89f015 KVM: x86 emulator: implement ENTER
Opcode C8.

Only ENTER with lexical nesting depth 0 is implemented, since others are
very rare.  We'll fail emulation if nonzero lexical depth is used so data
is not corrupted.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:03 +03:00
Avi Kivity
51ddff50cb KVM: x86 emulator: split push logic from push opcode emulation
This allows us to reuse the code without populating ctxt->src and
overriding ctxt->op_bytes.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:03 +03:00
Avi Kivity
361cad2b50 KVM: x86 emulator: fix byte-sized MOVZX/MOVSX
Commit 2adb5ad9fe removed ByteOp from MOVZX/MOVSX, replacing them by
SrcMem8, but neglected to fix the dependency in the emulation code
on ByteOp.  This caused the instruction not to have any effect in
some circumstances.

Fix by replacing the check for ByteOp with the equivalent src.op_bytes == 1.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:03 +03:00
Avi Kivity
2dd7caa092 KVM: x86 emulator: emulate LAHF
Opcode 9F.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:03 +03:00
Avi Kivity
96051572c8 KVM: x86 emulator: emulate SGDT/SIDT
Opcodes 0F 01 /0 and 0F 01 /1

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:02 +03:00
Avi Kivity
a6e3407bb1 KVM: Fix SS default ESP/EBP based addressing
We correctly default to SS when BP is used as a base in 16-bit address mode,
but we don't do that for 32-bit mode.

Fix by adjusting the default to SS when either ESP or EBP is used as the base
register.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:02 +03:00
Avi Kivity
f47cfa3174 KVM: x86 emulator: emulate LEAVE
Opcode c9; used by some variants of Windows during boot, in big real mode.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:01 +03:00
Avi Kivity
510425ff33 KVM: x86 emulator: fix LIDT/LGDT in long mode
The operand size for these instructions is 8 bytes in long mode, even without
a REX prefix.  Set it explicitly.

Triggered while booting Linux with emulate_invalid_guest_state=1.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:01 +03:00
Avi Kivity
79d5b4c3cd KVM: x86 emulator: allow loading null SS in long mode
Null SS is valid in long mode; allow loading it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:01 +03:00
Avi Kivity
6d6eede4a0 KVM: x86 emulator: emulate cpuid
Opcode 0F A2.

Used by Linux during the mode change trampoline while in a state that is
not virtualizable on vmx without unrestricted_guest, so we need to emulate
it is emulate_invalid_guest_state=1.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:00 +03:00
Avi Kivity
0017f93a27 KVM: x86 emulator: change ->get_cpuid() accessor to use the x86 semantics
Instead of getting an exact leaf, follow the spec and fall back to the last
main leaf instead.  This lets us easily emulate the cpuid instruction in the
emulator.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-07-09 14:19:00 +03:00
Joerg Roedel
d54e4237bc KVM: x86 emulator: convert bsf/bsr instructions to emulate_2op_SrcV_nobyte()
The instruction emulation for bsrw is broken in KVM because
the code always uses bsr with 32 or 64 bit operand size for
emulation. Fix that by using emulate_2op_SrcV_nobyte() macro
to use guest operand size for emulation.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-05-14 11:32:38 +03:00
Takuya Yoshikawa
9f4260e73a KVM: x86 emulator: Avoid pushing back ModRM byte fetched for group decoding
Although ModRM byte is fetched for group decoding, it is soon pushed
back to make decode_modrm() fetch it later again.

Now that ModRM flag can be found in the top level opcode tables, fetch
ModRM byte before group decoding to make the code simpler.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-05-06 16:15:58 +03:00
Takuya Yoshikawa
1c2545be05 KVM: x86 emulator: Move ModRM flags for groups to top level opcode tables
Needed for the following patch which simplifies ModRM fetching code.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-05-06 16:15:57 +03:00
Avi Kivity
38e8a2ddc9 KVM: x86 emulator: fix asm constraint in flush_pending_x87_faults
'bool' wants 8-bit registers.

Reported-by: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-24 17:16:17 +03:00
Avi Kivity
e59717550e KVM: x86 emulator: implement MMX MOVQ (opcodes 0f 6f, 0f 7f)
Needed by some framebuffer drivers.  See

https://bugzilla.kernel.org/show_bug.cgi?id=42779

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-16 20:36:16 -03:00
Avi Kivity
cbe2c9d30a KVM: x86 emulator: MMX support
General support for the MMX instruction set.  Special care is taken
to trap pending x87 exceptions so that they are properly reflected
to the guest.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-16 20:36:16 -03:00
Avi Kivity
3e114eb4db KVM: x86 emulator: implement movntps
Used to write to framebuffers (by at least Icaros).

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-16 20:36:16 -03:00
Stefan Hajnoczi
49597d8116 KVM: x86: emulate movdqa
An Ubuntu 9.10 Karmic Koala guest is unable to boot or install due to
missing movdqa emulation:

kvm_exit: reason EXCEPTION_NMI rip 0x7fef3e025a7b info 7fef3e799000 80000b0e
kvm_page_fault: address 7fef3e799000 error_code f
kvm_emulate_insn: 0:7fef3e025a7b: 66 0f 7f 07 (prot64)

movdqa %xmm0,(%rdi)

[avi: mark it explicitly aligned]

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-16 20:36:15 -03:00
Avi Kivity
1c11b37669 KVM: x86 emulator: add support for vector alignment
x86 defines three classes of vector instructions: explicitly
aligned (#GP(0) if unaligned, explicitly unaligned, and default
(which depends on the encoding: AVX is unaligned, SSE is aligned).

Add support for marking an instruction as explicitly aligned or
unaligned, and mark MOVDQU as unaligned.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-04-16 20:36:15 -03:00
Kevin Wolf
4cee4798a3 KVM: x86 emulator: Allow PM/VM86 switch during task switch
Task switches can switch between Protected Mode and VM86. The current
mode must be updated during the task switch emulation so that the new
segment selectors are interpreted correctly.

In order to let privilege checks succeed, rflags needs to be updated in
the vcpu struct as this causes a CPL update.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-08 14:10:29 +02:00
Kevin Wolf
66b0ab8fac KVM: x86 emulator: VM86 segments must have DPL 3
Setting the segment DPL to 0 for at least the VM86 code segment makes
the VM entry fail on VMX.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-08 14:10:27 +02:00
Kevin Wolf
7f3d35fddd KVM: x86 emulator: Fix task switch privilege checks
Currently, all task switches check privileges against the DPL of the
TSS. This is only correct for jmp/call to a TSS. If a task gate is used,
the DPL of this take gate is used for the check instead. Exceptions,
external interrupts and iret shouldn't perform any check.

[avi: kill kvm-kmod remnants]

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-08 14:10:26 +02:00
Avi Kivity
1a18a69b76 KVM: x86 emulator: reject SYSENTER in compatibility mode on AMD guests
If the guest thinks it's an AMD, it will not have prepared the SYSENTER MSRs,
and if the guest executes SYSENTER in compatibility mode, it will fails.

Detect this condition and #UD instead, like the spec says.

Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:57:20 +02:00
Avi Kivity
2adb5ad9fe KVM: x86 emulator: Remove byte-sized MOVSX/MOVZX hack
Currently we treat MOVSX/MOVZX with a byte source as a byte instruction,
and change the destination operand size with a hack.  Change it to be
a word instruction, so the destination receives its natural size, and
change the source to be SrcMem8.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-03-05 14:52:42 +02:00
Avi Kivity
28867cee75 KVM: x86 emulator: add 8-bit memory operands
Useful for MOVSX/MOVZX.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-03-05 14:52:42 +02:00
Stephan Bärwolf
c2226fc9e8 KVM: x86: fix missing checks in syscall emulation
On hosts without this patch, 32bit guests will crash (and 64bit guests
may behave in a wrong way) for example by simply executing following
nasm-demo-application:

    [bits 32]
    global _start
    SECTION .text
    _start: syscall

(I tested it with winxp and linux - both always crashed)

    Disassembly of section .text:

    00000000 <_start>:
       0:   0f 05                   syscall

The reason seems a missing "invalid opcode"-trap (int6) for the
syscall opcode "0f05", which is not available on Intel CPUs
within non-longmodes, as also on some AMD CPUs within legacy-mode.
(depending on CPU vendor, MSR_EFER and cpuid)

Because previous mentioned OSs may not engage corresponding
syscall target-registers (STAR, LSTAR, CSTAR), they remain
NULL and (non trapping) syscalls are leading to multiple
faults and finally crashs.

Depending on the architecture (AMD or Intel) pretended by
guests, various checks according to vendor's documentation
are implemented to overcome the current issue and behave
like the CPUs physical counterparts.

[mtosatti: cleanup/beautify code]

Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-02-01 11:43:40 +02:00
Avi Kivity
222d21aa07 KVM: x86 emulator: implement RDPMC (0F 33)
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:24:43 +02:00
Avi Kivity
80bdec64c0 KVM: x86 emulator: fix RDPMC privilege check
RDPMC is only privileged if CR4.PCE=0.  check_rdpmc() already implements this,
so all we need to do is drop the Priv flag.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:24:41 +02:00
Takuya Yoshikawa
e0dac408d0 KVM: x86 emulator: Use opcode::execute for Group 9 instruction
Group 9: 0F C7

Rename em_grp9() to em_cmpxchg8b() and register it.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:23:38 +02:00
Takuya Yoshikawa
c04ec8393f KVM: x86 emulator: Use opcode::execute for Group 4/5 instructions
Group 4: FE
Group 5: FF

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:23:36 +02:00
Takuya Yoshikawa
c15af35f54 KVM: x86 emulator: Use opcode::execute for Group 1A instruction
Group 1A: 8F

Register em_pop() directly and remove em_grp1a().

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:23:35 +02:00