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2013-11-29KVM: x86: fix emulation of "movzbl %bpl, %eax"Paolo Bonzini
commit daf727225b8abfdfe424716abac3d15a3ac5626a upstream. 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: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03KVM: fix sil/dil/bpl/spl in the mod/rm fieldsPaolo Bonzini
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 Bonzini
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>
2013-05-09KVM: emulator: emulate SALCPaolo Bonzini
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 Bonzini
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 Bonzini
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 Natapov
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 Natapov
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-14KVM: emulator: Do not fail on emulation of undefined opcodeGleb Natapov
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 Natapov
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 Wolf
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 Natapov
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 Kivity
'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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Kivity
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 Natapov
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 Natapov
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 Amit
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 Natapov
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 Torvalds
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 ...
2012-12-11KVM: emulator: fix real mode segment checks in address linearizationGleb Natapov
In real mode CS register is writable, so do not #GP on write. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-11-26x86, kvm: Remove incorrect redundant assembly constraintH. Peter Anvin
In __emulate_1op_rax_rdx, we use "+a" and "+d" which are input/output constraints, and *then* use "a" and "d" as input constraints. This is incorrect, but happens to work on some versions of gcc. However, it breaks gcc with -O0 and icc, and may break on future versions of gcc. Reported-and-tested-by: Melanie Blower <melanie.blower@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/B3584E72CFEBED439A3ECA9BCE67A4EF1B17AF90@FMSMSX107.amr.corp.intel.com Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-09-06KVM: emulator: optimize "rep ins" handlingGleb Natapov
Optimize "rep ins" by allowing emulator to write back more than one datum at a time. Introduce new operand type OP_MEM_STR which tells writeback() that dst contains pointer to an array that should be written back as opposite to just one data element. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-06KVM: emulator: string_addr_inc() cleanupGleb Natapov
Remove unneeded segment argument. Address structure already has correct segment which was put there during decode. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-06KVM: emulator: make x86 emulation modes enum instead of definesGleb Natapov
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-05KVM: x86 emulator: constify emulate_opsMathias Krause
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>
2012-09-05KVM: x86 emulator: mark opcode tables constMathias Krause
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>
2012-09-05KVM: x86 emulator: use aligned variants of SSE register opsMathias Krause
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>
2012-08-27KVM: x86 emulator: Fix #GP error code during linearizationAvi Kivity
We want the segment selector, nor segment number. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-27KVM: x86 emulator: Check segment limits in real mode tooAvi Kivity
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>
2012-08-27KVM: x86 emulator: Leave segment limit and attributs alone in real modeAvi Kivity
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>
2012-08-27KVM: x86 emulator: access GPRs on demandAvi Kivity
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>
2012-08-26Merge remote-tracking branch 'upstream/master' into queueMarcelo Tosatti
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>
2012-08-22KVM: x86 emulator: use stack size attribute to mask rsp in stack opsAvi Kivity
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 a27685c33acccce (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>
2012-07-26KVM: x86 emulator: drop unneeded call to get_segment()Gleb Natapov
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>
2012-07-26KVM: x86 emulator: simplify read_emulatedXiao Guangrong
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>
2012-07-20KVM: x86: Fix typos in emulate.cGuo Chao
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>