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2013-11-05KVM: emulator: cleanup decode_register_operand() a bitGleb Natapov1-7/+3
Make code shorter. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-05KVM: emulator: check rex prefix inside decode_register()Gleb Natapov1-11/+7
All decode_register() callers check if instruction has rex prefix to properly decode one byte operand. It make sense to move the check inside. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-03KVM: x86: fix emulation of "movzbl %bpl, %eax"Paolo Bonzini1-1/+4
When I was looking at RHEL5.9's failure to start with unrestricted_guest=0/emulate_invalid_guest_state=1, I got it working with a slightly older tree than kvm.git. I now debugged the remaining failure, which was introduced by commit 660696d1 (KVM: X86 emulator: fix source operand decoding for 8bit mov[zs]x instructions, 2013-04-24) introduced a similar mis-emulation to the one in commit 8acb4207 (KVM: fix sil/dil/bpl/spl in the mod/rm fields, 2013-05-30). The incorrect decoding occurs in 8-bit movzx/movsx instructions whose 8-bit operand is sil/dil/bpl/spl. Needless to say, "movzbl %bpl, %eax" does occur in RHEL5.9's decompression prolog, just a handful of instructions before finally giving control to the decompressed vmlinux and getting out of the invalid guest state. Because OpMem8 bypasses decode_modrm, the same handling of the REX prefix must be applied to OpMem8. Reported-by: Michele Baldessari <michele@redhat.com> Cc: stable@vger.kernel.org Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-31KVM: x86: emulate SAHF instructionPaolo Bonzini1-1/+14
Yet another instruction that we fail to emulate, this time found in Windows 2008R2 32-bit. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30kvm: Emulate MOVBEBorislav Petkov1-4/+49
This basically came from the need to be able to boot 32-bit Atom SMP guests on an AMD host, i.e. a host which doesn't support MOVBE. As a matter of fact, qemu has since recently received MOVBE support but we cannot share that with kvm emulation and thus we have to do this in the host. We're waay faster in kvm anyway. :-) So, we piggyback on the #UD path and emulate the MOVBE functionality. With it, an 8-core SMP guest boots in under 6 seconds. Also, requesting MOVBE emulation needs to happen explicitly to work, i.e. qemu -cpu n270,+movbe... Just FYI, a fairly straight-forward boot of a MOVBE-enabled 3.9-rc6+ kernel in kvm executes MOVBE ~60K times. Signed-off-by: Andre Przywara <andre@andrep.de> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30kvm, emulator: Add initial three-byte insns supportBorislav Petkov1-0/+30
Add initial support for handling three-byte instructions in the emulator. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30kvm, emulator: Rename VendorSpecific flagBorislav Petkov1-7/+7
Call it EmulateOnUD which is exactly what we're trying to do with vendor-specific instructions. Rename ->only_vendor_specific_insn to something shorter, while at it. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30kvm, emulator: Use opcode lengthBorislav Petkov1-2/+3
Add a field to the current emulation context which contains the instruction opcode length. This will streamline handling of opcodes of different length. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-17KVM: x86 emulator: emulate RETF immBruce Rogers1-1/+13
Opcode CA This gets used by a DOS based NetWare guest. Signed-off-by: Bruce Rogers <brogers@suse.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-03Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-282/+109
Pull KVM fixes from Paolo Bonzini: "On the x86 side, there are some optimizations and documentation updates. The big ARM/KVM change for 3.11, support for AArch64, will come through Catalin Marinas's tree. s390 and PPC have misc cleanups and bugfixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (87 commits) KVM: PPC: Ignore PIR writes KVM: PPC: Book3S PR: Invalidate SLB entries properly KVM: PPC: Book3S PR: Allow guest to use 1TB segments KVM: PPC: Book3S PR: Don't keep scanning HPTEG after we find a match KVM: PPC: Book3S PR: Fix invalidation of SLB entry 0 on guest entry KVM: PPC: Book3S PR: Fix proto-VSID calculations KVM: PPC: Guard doorbell exception with CONFIG_PPC_DOORBELL KVM: Fix RTC interrupt coalescing tracking kvm: Add a tracepoint write_tsc_offset KVM: MMU: Inform users of mmio generation wraparound KVM: MMU: document fast invalidate all mmio sptes KVM: MMU: document fast invalidate all pages KVM: MMU: document fast page fault KVM: MMU: document mmio page fault KVM: MMU: document write_flooding_count KVM: MMU: document clear_spte_count KVM: MMU: drop kvm_mmu_zap_mmio_sptes KVM: MMU: init kvm generation close to mmio wrap-around value KVM: MMU: add tracepoint for check_mmio_spte KVM: MMU: fast invalidate all mmio sptes ...
2013-06-03KVM: fix sil/dil/bpl/spl in the mod/rm fieldsPaolo Bonzini1-1/+4
The x86-64 extended low-byte registers were fetched correctly from reg, but not from mod/rm. This fixes another bug in the boot of RHEL5.9 64-bit, but it is still not enough. Cc: <stable@vger.kernel.org> # 3.9 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-03KVM: Emulate multibyte NOPPaolo Bonzini1-1/+3
This is encountered when booting RHEL5.9 64-bit. There is another bug after this one that is not a simple emulation failure, but this one lets the boot proceed a bit. Cc: <stable@vger.kernel.org> # 3.9 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: convert XADD to fastopAvi Kivity1-7/+3
Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: drop unused old-style inline emulationAvi Kivity1-198/+0
Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: convert DIV/IDIV to fastopAvi Kivity1-25/+26
Since DIV and IDIV can generate exceptions, we need an additional output parameter indicating whether an execption has occured. To avoid increasing register pressure on i386, we use %rsi, which is already allocated for the fastop code pointer. Gleb: added comment about fop usage as exception indication. Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: convert single-operand MUL/IMUL to fastopAvi Kivity1-19/+16
Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: Switch fastop src operand to RDXAvi Kivity1-13/+13
This makes OpAccHi useful. Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: switch MUL/DIV to DstXaccAvi Kivity1-7/+8
Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: decode extended accumulator explicityAvi Kivity1-0/+24
Single-operand MUL and DIV access an extended accumulator: AX for byte instructions, and DX:AX, EDX:EAX, or RDX:RAX for larger-sized instructions. Add support for fetching the extended accumulator. In order not to change things too much, RDX is loaded into Src2, which is already loaded by fastop(). This avoids increasing register pressure on i386. Gleb: disable src writeback for ByteOp div/mul. Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-21KVM: x86 emulator: add support for writing back the source operandAvi Kivity1-21/+27
Some instructions write back the source operand, not just the destination. Add support for doing this via the decode flags. Gleb: add BUG_ON() to prevent source to be memory operand. Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09KVM: emulator: emulate SALCPaolo Bonzini1-1/+5
This is an almost-undocumented instruction available in 32-bit mode. I say "almost" undocumented because AMD documents it in their opcode maps just to say that it is unavailable in 64-bit mode (sections "A.2.1 One-Byte Opcodes" and "B.3 Invalid and Reassigned Instructions in 64-Bit Mode"). It is roughly equivalent to "sbb %al, %al" except it does not set the flags. Use fastop to emulate it, but do not use the opcode directly because it would fail if the host is 64-bit! Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Cc: stable@vger.kernel.org # 3.9 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09KVM: emulator: emulate XLATPaolo Bonzini1-1/+14
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1. It is just a MOV in disguise, with a funny source address. Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Cc: stable@vger.kernel.org # 3.9 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-09KVM: emulator: emulate AAMPaolo Bonzini1-1/+24
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1. AAM needs the source operand to be unsigned; do the same in AAD as well for consistency, even though it does not affect the result. Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Cc: stable@vger.kernel.org # 3.9 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-25KVM: X86 emulator: fix source operand decoding for 8bit mov[zs]x instructionsGleb Natapov1-0/+4
Source operand for one byte mov[zs]x is decoded incorrectly if it is in high byte register. Fix that. Cc: stable@vger.kernel.org Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-14KVM: emulator: mark 0xff 0x7d opcode as undefined.Gleb Natapov1-1/+1
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-14KVM: emulator: Do not fail on emulation of undefined opcodeGleb Natapov1-2/+3
Emulation of undefined opcode should inject #UD instead of causing emulation failure. Do that by moving Undefined flag check to emulation stage and injection #UD there. Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-14KVM: emulator: fix unimplemented instruction detectionGleb Natapov1-3/+4
Unimplemented instruction detection is broken for group instructions since it relies on "flags" field of opcode to be zero, but all instructions in a group inherit flags from a group encoding. Fix that by having a separate flag for unimplemented instructions. Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-11KVM: x86 emulator: Fix segment loading in VM86Kevin Wolf1-3/+12
This fixes a regression introduced in commit 03ebebeb1 ("KVM: x86 emulator: Leave segment limit and attributs alone in real mode"). The mentioned commit changed the segment descriptors for both real mode and VM86 to only update the segment base instead of creating a completely new descriptor with limit 0xffff so that unreal mode keeps working across a segment register reload. This leads to an invalid segment descriptor in the eyes of VMX, which seems to be okay for real mode because KVM will fix it up before the next VM entry or emulate the state, but it doesn't do this if the guest is in VM86, so we end up with: KVM: entry failed, hardware error 0x80000021 Fix this by effectively reverting commit 03ebebeb1 for VM86 and leaving it only in place for real mode, which is where it's really needed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-02-13x86 emulator: fix parity calculation for AAD instructionGleb Natapov1-8/+5
Reported-by: Paolo Bonzini <pbonzini@redhat.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-01-27KVM: x86 emulator: fix test_cc() build failure on i386Avi Kivity1-1/+1
'pushq' doesn't exist on i386. Replace with 'push', which should work since the operand is a register. Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-01-23KVM: x86 emulator: convert a few freestanding emulations to fastopAvi Kivity1-3/+3
Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: rearrange fastop definitionsAvi Kivity1-35/+35
Make fastop opcodes usable in other emulations. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: convert 2-operand IMUL to fastopAvi Kivity1-8/+6
Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: convert BT/BTS/BTR/BTC/BSF/BSR to fastopAvi Kivity1-50/+26
Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: convert INC/DEC to fastopAvi Kivity1-17/+7
Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: covert SETCC to fastopAvi Kivity1-31/+29
This is a bit of a special case since we don't have the usual byte/word/long/quad switch; instead we switch on the condition code embedded in the instruction. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: convert shift/rotate instructions to fastopAvi Kivity1-41/+31
SHL, SHR, ROL, ROR, RCL, RCR, SAR, SAL Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-23KVM: x86 emulator: Convert SHLD, SHRD to fastopAvi Kivity1-12/+21
Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: convert basic ALU ops to fastopAvi Kivity1-78/+34
Opcodes: TEST CMP ADD ADC SUB SBB XOR OR AND Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: add macros for defining 2-operand fastop emulationAvi Kivity1-0/+12
Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: convert NOT, NEG to fastopAvi Kivity1-13/+4
Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: mark CMP, CMPS, SCAS, TEST as NoWriteAvi Kivity1-12/+8
Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: introduce NoWrite flagAvi Kivity1-0/+4
Instead of disabling writeback via OP_NONE, just specify NoWrite. Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: Support for declaring single operand fastopsAvi Kivity1-0/+25
Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-09KVM: x86 emulator: framework for streamlining arithmetic opcodesAvi Kivity1-0/+41
We emulate arithmetic opcodes by executing a "similar" (same operation, different operands) on the cpu. This ensures accurate emulation, esp. wrt. eflags. However, the prologue and epilogue around the opcode is fairly long, consisting of a switch (for the operand size) and code to load and save the operands. This is repeated for every opcode. This patch introduces an alternative way to emulate arithmetic opcodes. Instead of the above, we have four (three on i386) functions consisting of just the opcode and a ret; one for each operand size. For example: .align 8 em_notb: not %al ret .align 8 em_notw: not %ax ret .align 8 em_notl: not %eax ret .align 8 em_notq: not %rax ret The prologue and epilogue are shared across all opcodes. Note the functions use a special calling convention; notably eflags is an input/output parameter and is not clobbered. Rather than dispatching the four functions through a jump table, the functions are declared as a constant size (8) so their address can be calculated. Acked-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi.kivity@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-02KVM: emulator: implement fninit, fnstsw, fnstcwGleb Natapov1-1/+125
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-02KVM: emulator: drop RPL check from linearize() functionGleb Natapov1-6/+1
According to Intel SDM Vol3 Section 5.5 "Privilege Levels" and 5.6 "Privilege Level Checking When Accessing Data Segments" RPL checking is done during loading of a segment selector, not during data access. We already do checking during segment selector loading, so drop the check during data access. Checking RPL during data access triggers #GP if after transition from real mode to protected mode RPL bits in a segment selector are set. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-12-13KVM: x86: fix mov immediate emulation for 64-bit operandsNadav Amit1-2/+10
MOV immediate instruction (opcodes 0xB8-0xBF) may take 64-bit operand. The previous emulation implementation assumes the operand is no longer than 32. Adding OpImm64 for this matter. Fixes https://bugzilla.redhat.com/show_bug.cgi?id=881579 Signed-off-by: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-12-13KVM: emulator: implement AAD instructionGleb Natapov1-1/+22
Windows2000 uses it during boot. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=50921 Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-12-13Merge tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-2/+3
Pull KVM updates from Marcelo Tosatti: "Considerable KVM/PPC work, x86 kvmclock vsyscall support, IA32_TSC_ADJUST MSR emulation, amongst others." Fix up trivial conflict in kernel/sched/core.c due to cross-cpu migration notifier added next to rq migration call-back. * tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (156 commits) KVM: emulator: fix real mode segment checks in address linearization VMX: remove unneeded enable_unrestricted_guest check KVM: VMX: fix DPL during entry to protected mode x86/kexec: crash_vmclear_local_vmcss needs __rcu kvm: Fix irqfd resampler list walk KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary KVM: MMU: optimize for set_spte KVM: PPC: booke: Get/set guest EPCR register using ONE_REG interface KVM: PPC: bookehv: Add EPCR support in mtspr/mfspr emulation KVM: PPC: bookehv: Add guest computation mode for irq delivery KVM: PPC: Make EPCR a valid field for booke64 and bookehv KVM: PPC: booke: Extend MAS2 EPN mask for 64-bit KVM: PPC: e500: Mask MAS2 EPN high 32-bits in 32/64 tlbwe emulation KVM: PPC: Mask ea's high 32-bits in 32/64 instr emulation KVM: PPC: e500: Add emulation helper for getting instruction ea KVM: PPC: bookehv64: Add support for interrupt handling KVM: PPC: bookehv: Remove GET_VCPU macro from exception handler KVM: PPC: booke: Fix get_tb() compile error on 64-bit KVM: PPC: e500: Silence bogus GCC warning in tlb code ...