Commit Graph

602031 Commits

Author SHA1 Message Date
Radim Krčmář 64aa47bfc4 KVM: x86: add kvm_apic_map_get_dest_lapic
kvm_irq_delivery_to_apic_fast and kvm_intr_is_single_vcpu_fast both
compute the interrupt destination.  Factor the code.

'struct kvm_lapic **dst = NULL' had to be added to silence GCC.
GCC might complain about potential NULL access in the future, because it
missed conditions that avoided uninitialized uses of dst.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:51 +02:00
Radim Krčmář 757883de41 KVM: x86: bump KVM_SOFT_MAX_VCPUS to 240
240 has been well tested by Red Hat.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:51 +02:00
Bandan Das 02120c45b0 kvm: vmx: advertise support for ept execute only
MMU now knows about execute only mappings, so
advertise the feature to L1 hypervisors

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:50 +02:00
Bandan Das d95c55687e kvm: mmu: track read permission explicitly for shadow EPT page tables
To support execute only mappings on behalf of L1 hypervisors,
reuse ACC_USER_MASK to signify if the L1 hypervisor has the R bit
set.

For the nested EPT case, we assumed that the U bit was always set
since there was no equivalent in EPT page tables.  Strictly
speaking, this was not necessary because handle_ept_violation
never set PFERR_USER_MASK in the error code (uf=0 in the
parlance of update_permission_bitmask).  We now have to set
both U and UF correctly, respectively in FNAME(gpte_access)
and in handle_ept_violation.

Also in handle_ept_violation bit 3 of the exit qualification is
not enough to detect a present PTE; all three bits 3-5 have to
be checked.

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:50 +02:00
Bandan Das ffb128c89b kvm: mmu: don't set the present bit unconditionally
To support execute only mappings on behalf of L1
hypervisors, we need to teach set_spte() to honor all three of
L1's XWR bits.  As a start, add a new variable "shadow_present_mask"
that will be set for non-EPT shadow paging and clear for EPT.

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:14 +02:00
Bandan Das 812f30b234 kvm: mmu: remove is_present_gpte()
We have two versions of the above function.
To prevent confusion and bugs in the future, remove
the non-FNAME version entirely and replace all calls
with the actual check.

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:02:47 +02:00
Bandan Das 8d5cf1610d kvm: mmu: extend the is_present check to 32 bits
This is safe because this function is called
on host controlled page table and non-present/non-MMIO
sptes never use bits 1..31. For the EPT case, this
ensures that cases where only the execute bit is set
is marked valid.

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:02:46 +02:00
Paolo Bonzini 6d5315b3a6 Merge branch 'kvm-ppc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD 2016-07-11 18:10:06 +02:00
Paolo Bonzini 8391ce447f KVM: VMX: introduce vm_{entry,exit}_control_reset_shadow
There is no reason to read the entry/exit control fields of the
VMCS and immediately write back the same value.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-11 10:07:49 +02:00
Paolo Bonzini 9314006db8 KVM: nVMX: keep preemption timer enabled during L2 execution
Because the vmcs12 preemption timer is emulated through a separate hrtimer,
we can keep on using the preemption timer in the vmcs02 to emulare L1's
TSC deadline timer.

However, the corresponding bit in the pin-based execution control field
must be kept consistent between vmcs01 and vmcs02.  On vmentry we copy
it into the vmcs02; on vmexit the preemption timer must be disabled in
the vmcs01 if a preemption timer vmexit happened while in guest mode.

The preemption timer value in the vmcs02 is set by vmx_vcpu_run, so it
need not be considered in prepare_vmcs02.

Cc: Yunhong Jiang <yunhong.jiang@intel.com>
Cc: Haozhong Zhang <haozhong.zhang@intel.com>
Tested-by: Wanpeng Li <kernellwp@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-11 09:49:29 +02:00
Wanpeng Li 55123e3c86 KVM: nVMX: avoid incorrect preemption timer vmexit in nested guest
The preemption timer for nested VMX is emulated by hrtimer which is started on L2
entry, stopped on L2 exit and evaluated via the check_nested_events hook. However,
nested_vmx_exit_handled is always returning true for preemption timer vmexit.  Then,
the L1 preemption timer vmexit is captured and be treated as a L2 preemption
timer vmexit, causing NULL pointer dereferences or worse in the L1 guest's
vmexit handler:

    BUG: unable to handle kernel NULL pointer dereference at           (null)
    IP: [<          (null)>]           (null)
    PGD 0
    Oops: 0010 [#1] SMP
    Call Trace:
     ? kvm_lapic_expired_hv_timer+0x47/0x90 [kvm]
     handle_preemption_timer+0xe/0x20 [kvm_intel]
     vmx_handle_exit+0x169/0x15a0 [kvm_intel]
     ? kvm_arch_vcpu_ioctl_run+0xd5d/0x19d0 [kvm]
     kvm_arch_vcpu_ioctl_run+0xdee/0x19d0 [kvm]
     ? kvm_arch_vcpu_ioctl_run+0xd5d/0x19d0 [kvm]
     ? vcpu_load+0x1c/0x60 [kvm]
     ? kvm_arch_vcpu_load+0x57/0x260 [kvm]
     kvm_vcpu_ioctl+0x2d3/0x7c0 [kvm]
     do_vfs_ioctl+0x96/0x6a0
     ? __fget_light+0x2a/0x90
     SyS_ioctl+0x79/0x90
     do_syscall_64+0x68/0x180
     entry_SYSCALL64_slow_path+0x25/0x25
    Code:  Bad RIP value.
    RIP  [<          (null)>]           (null)
     RSP <ffff8800b5263c48>
    CR2: 0000000000000000
    ---[ end trace 9c70c48b1a2bc66e ]---

This can be reproduced readily by preemption timer enabled on L0 and disabled
on L1.

Return false since preemption timer vmexits must never be reflected to L2.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Yunhong Jiang <yunhong.jiang@intel.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-11 09:49:26 +02:00
Paolo Bonzini 1c17c3e6bf KVM: VMX: reflect broken preemption timer in vmcs_config
Simplify cpu_has_vmx_preemption_timer.  This is consistent with the
rest of setup_vmcs_config and preparatory for the next patch.

Tested-by: Wanpeng Li <kernellwp@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-11 09:48:49 +02:00
James Hogan 8426097258 MIPS: KVM: Emulate generic QEMU machine on r6 T&E
Default the guest PRId register to represent a generic QEMU machine
instead of a 24kc on MIPSr6. 24kc isn't supported by r6 Linux kernels.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:20 +02:00
James Hogan 8eeab81c3d MIPS: KVM: Decode RDHWR more strictly
When KVM emulates the RDHWR instruction, decode the instruction more
strictly. The rs field (bits 25:21) should be zero, as should bits 10:9.
Bits 8:6 is the register select field in MIPSr6, so we aren't strict
about those bits (no other operations should use that encoding space).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:18 +02:00
James Hogan 5cc4aafced MIPS: KVM: Recognise r6 CACHE encoding
Recognise the new MIPSr6 CACHE instruction encoding rather than the
pre-r6 one when an r6 kernel is being built. A SPECIAL3 opcode is used
and the immediate field is reduced to 9 bits wide since MIPSr6.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:17 +02:00
James Hogan 2e0badfaac MIPS: KVM: Support r6 compact branch emulation
Add support in KVM for emulation of instructions in the forbidden slot
of MIPSr6 compact branches. If we hit an exception on the forbidden
slot, then the branch must not have been taken, which makes calculation
of the resume PC trivial.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:16 +02:00
James Hogan 70e92c7ee9 MIPS: KVM: Don't save/restore lo/hi for r6
MIPSr6 doesn't have lo/hi registers, so don't bother saving or
restoring them, and don't expose them to userland with the KVM ioctl
interface either.

In fact the lo/hi registers aren't callee saved in the MIPS ABIs anyway,
so there is no need to preserve the host lo/hi values at all when
transitioning to and from the guest (which happens via a function call).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:14 +02:00
James Hogan d85ebff007 MIPS: KVM: Fix pre-r6 ll/sc instructions on r6
The atomic KVM register access macros in kvm_host.h (for the guest Cause
register with KVM in trap & emulate mode) use ll/sc instructions,
however they still .set mips3, which causes pre-MIPSr6 instruction
encodings to be emitted, even for a MIPSr6 build.

Fix it to use MIPS_ISA_ARCH_LEVEL as other parts of arch/mips already
do.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:13 +02:00
James Hogan d14740fed8 MIPS: KVM: Fix fpu.S misassembly with r6
__kvm_save_fpu and __kvm_restore_fpu use .set mips64r2 so that they can
access the odd FPU registers as well as the even, however this causes
misassembly of the return instruction on MIPSr6.

Fix by replacing .set mips64r2 with .set fp=64, which doesn't change the
architecture revision.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:11 +02:00
Paul Burton 1b49260006 MIPS: inst.h: Rename cbcond{0,1}_op to pop{1,3}0_op
The opcodes currently defined in inst.h as cbcond0_op & cbcond1_op are
actually defined in the MIPS base instruction set manuals as pop10 &
pop30 respectively. Rename them as such, for consistency with the
documentation.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:09:07 +02:00
Paul Burton 1c66b79bb3 MIPS: inst.h: Rename b{eq,ne}zcji[al]c_op to pop{6,7}6_op
The opcodes currently defined in inst.h as beqzcjic_op & bnezcjialc_op
are actually defined in the MIPS base instruction set manuals as pop66 &
pop76 respectively. Rename them as such, for consistency with the
documentation.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:59 +02:00
James Hogan eadfb501a5 MIPS: KVM: Save k0 straight into VCPU structure
Currently on a guest exception the guest's k0 register is saved to the
scratch temp register and the guest k1 saved to the exception base
address + 0x3000 using k0 to extract the Exception Base field of the
EBase register and as the base operand to the store. Both are then
copied into the VCPU structure after the other general purpose registers
have been saved there.

This bouncing to exception base + 0x3000 is not actually necessary as
the VCPU pointer can be determined and written through just as easily
with only a single spare register. The VCPU pointer is already needed in
k1 for saving the other GP registers, so lets save the guest k0 register
straight into the VCPU structure through k1, first saving k1 into the
scratch temp register instead of k0.

This could potentially pave the way for having a single exception base
area for use by all guests.

The ehb after saving the k register to the scratch temp register is also
delayed until just before it needs to be read back.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:57 +02:00
James Hogan 1f9ca62cbc MIPS: KVM: Relative branch to common exit handler
Use a relative branch to get from the individual exception vectors to
the common guest exit handler, rather than loading the address of the
exit handler and jumping to it.

This is made easier due to the fact we are now generating the entry code
dynamically. This will also allow the exception code to be further
reduced in future patches.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:55 +02:00
James Hogan 1e5217f542 MIPS: KVM: Dynamically choose scratch registers
Scratch cop0 registers are needed by KVM to be able to save/restore all
the GPRs, including k0/k1, and for storing the VCPU pointer. However no
registers are universally suitable for these purposes, so the decision
should be made at runtime.

Until now, we've used DDATA_LO to store the VCPU pointer, and ErrorEPC
as a temporary. It could be argued that this is abuse of those
registers, and DDATA_LO is known not to be usable on certain
implementations (Cavium Octeon). If KScratch registers are present, use
them instead.

We save & restore the temporary register in addition to the VCPU pointer
register when using a KScratch register for it, as it may be used for
normal host TLB handling too.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:54 +02:00
James Hogan 025014e3fb MIPS: KVM: Drop redundant restore of DDATA_LO
On return from the exit handler to the host (without re-entering the
guest) we restore the saved value of the DDATA_LO register which we use
as a scratch register. However we've already restored it ready for
calling the exit handler so there is no need to do it again, so drop
that code.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:53 +02:00
James Hogan 38ea7a715d MIPS: KVM: Check MSA presence at uasm time
Check for presence of MSA at uasm assembly time rather than at runtime
in the generated KVM host entry code. This optimises the guest exit path
by eliminating the MSA code entirely if not present, and eliminating the
read of Config3.MSAP and conditional branch if MSA is present.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:51 +02:00
James Hogan d37f4038d1 MIPS: KVM: Omit FPU handling entry code if possible
The FPU handling code on entry from guest is unnecessary if no FPU is
present, so allow it to be dropped at uasm assembly time.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:50 +02:00
James Hogan 9c98865840 MIPS: KVM: Drop now unused asm offsets
Now that locore.S is converted to uasm, remove a bunch of the assembly
offset definitions created by asm-offsets.c, including the CPUINFO_ ones
for reading the variable asid mask, and the non FPU/MSA related VCPU_
definitions. KVM's fpu.S and msa.S still use the remaining definitions.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:48 +02:00
James Hogan d7b8f890b6 MIPS: KVM: Add dumping of generated entry code
Dump the generated entry code with pr_debug(), similar to how it is done
in tlbex.c, so it can be more easily debugged.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:47 +02:00
James Hogan 90e9311a34 MIPS; KVM: Convert exception entry to uasm
Convert the whole of locore.S (assembly to enter guest and handle
exception entry) to be generated dynamically with uasm. This is done
with minimal changes to the resulting code.

The main changes are:
- Some constants are generated by uasm using LUI+ADDIU instead of
  LUI+ORI.
- Loading of lo and hi are swapped around in vcpu_run but not when
  resuming the guest after an exit. Both bits of logic are now generated
  by the same code.
- Register MOVEs in uasm use different ADDU operand ordering to GNU as,
  putting zero register into rs instead of rt.
- The JALR.HB to call the C exit handler is switched to JALR, since the
  hazard barrier would appear to be unnecessary.

This will allow further optimisation in the future to dynamically handle
the capabilities of the CPU.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:46 +02:00
James Hogan 6f63405cb6 MIPS: uasm: Add r6 MUL encoding
Add the R6 MUL instruction encoding for 3 operand signed multiply to
uasm so that KVM can use uasm for generating its entry point code at
runtime on R6.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:40 +02:00
James Hogan 9f730a60e5 MIPS: uasm: Add MTHI/MTLO instructions
Add MTHI/MTLO instructions for writing to the hi & lo registers to uasm
so that KVM can use uasm for generating its entry point code at runtime.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:35 +02:00
James Hogan 61c64cf99a MIPS: uasm: Add DI instruction
Add DI instruction for disabling interrupts to uasm so that KVM can use
uasm for generating its entry point code at runtime.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:29 +02:00
James Hogan 59e3559f48 MIPS: uasm: Add CFCMSA/CTCMSA instructions
Add CFCMSA/CTCMSA instructions for accessing MSA control registers to
uasm so that KVM can use uasm for generating its entry point code at
runtime.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:20 +02:00
James Hogan c29732a179 MIPS: uasm: Add CFC1/CTC1 instructions
Add CFC1/CTC1 instructions for accessing FP control registers to uasm so
that KVM can use uasm for generating its entry point code at runtime.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 16:08:11 +02:00
Paolo Bonzini 77cb7a3e15 KVM: s390: Fix for kvm/next (4.8) part 3
This contains a fix for PER ifetch events. As we now have a handler
 for a problem state instruction (sthyi) that could be stepped with a
 debugger we should try to do the right thing regarding PER in our
 instruction handlers.  With this fix the handling for intercepted
 instructions is fixed in general, thus fixing other oddball cases as
 well (e.g. kprobes single stepping)
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Merge tag 'kvm-s390-next-4.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fix for kvm/next (4.8) part 3

This contains a fix for PER ifetch events. As we now have a handler
for a problem state instruction (sthyi) that could be stepped with a
debugger we should try to do the right thing regarding PER in our
instruction handlers.  With this fix the handling for intercepted
instructions is fixed in general, thus fixing other oddball cases as
well (e.g. kprobes single stepping)
2016-07-05 14:42:00 +02:00
Wei Yongjun 03f6a22a39 KVM: x86: Use ARRAY_SIZE instead of dividing sizeof array with sizeof an element
Use ARRAY_SIZE instead of dividing sizeof array with sizeof an element

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 14:41:45 +02:00
Paolo Bonzini add6a0cd1c KVM: MMU: try to fix up page faults before giving up
The vGPU folks would like to trap the first access to a BAR by setting
vm_ops on the VMAs produced by mmap-ing a VFIO device.  The fault handler
then can use remap_pfn_range to place some non-reserved pages in the VMA.

This kind of VM_PFNMAP mapping is not handled by KVM, but follow_pfn
and fixup_user_fault together help supporting it.  The patch also supports
VM_MIXEDMAP vmas where the pfns are not reserved and thus subject to
reference counting.

Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Neo Jia <cjia@nvidia.com>
Reported-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 14:41:26 +02:00
Paolo Bonzini 92176a8ede KVM: MMU: prepare to support mapping of VM_IO and VM_PFNMAP frames
Handle VM_IO like VM_PFNMAP, as is common in the rest of Linux; extract
the formula to convert hva->pfn into a new function, which will soon
gain more capabilities.

Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-05 14:41:03 +02:00
David Hildenbrand 5ffe466cd3 KVM: s390: inject PER i-fetch events on applicable icpts
In case we have to emuluate an instruction or part of it (instruction,
partial instruction, operation exception), we have to inject a PER
instruction-fetching event for that instruction, if hardware told us to do
so.

In case we retry an instruction, we must not inject the PER event.

Please note that we don't filter the events properly yet, so guest
debugging will be visible for the guest.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-07-05 12:02:56 +02:00
Wanpeng Li 196f20ca52 KVM: vmx: fix missed cancellation of TSC deadline timer
INFO: rcu_sched detected stalls on CPUs/tasks:
 1-...: (11800 GPs behind) idle=45d/140000000000000/0 softirq=0/0 fqs=21663
 (detected by 0, t=65016 jiffies, g=11500, c=11499, q=719)
Task dump for CPU 1:
qemu-system-x86 R  running task        0  3529   3525 0x00080808
 ffff8802021791a0 ffff880212895040 0000000000000001 00007f1c2c00db40
 ffff8801dd20fcd3 ffffc90002b98000 ffff8801dd20fc88 ffff8801dd20fcf8
 0000000000000286 ffff8801dd2ac538 ffff8801dd20fcc0 ffffffffc06949c9
Call Trace:
? kvm_write_guest_cached+0xb9/0x160 [kvm]
? __delay+0xf/0x20
? wait_lapic_expire+0x14a/0x200 [kvm]
? kvm_arch_vcpu_ioctl_run+0xcbe/0x1b00 [kvm]
? kvm_arch_vcpu_ioctl_run+0xe34/0x1b00 [kvm]
? kvm_vcpu_ioctl+0x2d3/0x7c0 [kvm]
? __fget+0x5/0x210
? do_vfs_ioctl+0x96/0x6a0
? __fget_light+0x2a/0x90
? SyS_ioctl+0x79/0x90
? do_syscall_64+0x7c/0x1e0
? entry_SYSCALL64_slow_path+0x25/0x25

This can be reproduced readily by running a full dynticks guest(since hrtimer
in guest is heavily used) w/ lapic_timer_advance disabled.

If fail to program hardware preemption timer, we will fallback to hrtimer based
method, however, a previous programmed preemption timer miss to cancel in this
scenario which results in one hardware preemption timer and one hrtimer emulated
tsc deadline timer run simultaneously. So sometimes the target guest deadline
tsc is earlier than guest tsc, which leads to the computation in vmx_set_hv_timer
can underflow and cause delta_tsc to be set a huge value, then host soft lockup
as above.

This patch fix it by cancelling the previous programmed preemption timer if there
is once we failed to program the new preemption timer and fallback to hrtimer
based method.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:42 +02:00
Wanpeng Li bd97ad0e7e KVM: x86: introduce cancel_hv_tscdeadline
Introduce cancel_hv_tscdeadline() to encapsulate preemption
timer cancel stuff.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:41 +02:00
Paolo Bonzini 9175d2e97b KVM: vmx: fix underflow in TSC deadline calculation
If the TSC deadline timer is programmed really close to the deadline or
even in the past, the computation in vmx_set_hv_timer can underflow and
cause delta_tsc to be set to a huge value.  This generally results
in vmx_set_hv_timer returning -ERANGE, but we can fix it by limiting
delta_tsc to be positive or zero.

Reported-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:39 +02:00
Paolo Bonzini f2485b3e0c KVM: x86: use guest_exit_irqoff
This gains a few clock cycles per vmexit.  On Intel there is no need
anymore to enable the interrupts in vmx_handle_external_intr, since
we are using the "acknowledge interrupt on exit" feature.  AMD
needs to do that, and must be careful to avoid the interrupt shadow.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:38 +02:00
Paolo Bonzini 91fa0f8e9e KVM: x86: always use "acknowledge interrupt on exit"
This is necessary to simplify handle_external_intr in the next patch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:36 +02:00
Paolo Bonzini 6edaa5307f KVM: remove kvm_guest_enter/exit wrappers
Use the functions from context_tracking.h directly.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:21 +02:00
Paolo Bonzini ebaac17362 context_tracking: move rcu_virt_note_context_switch out of kvm_host.h
Make kvm_guest_{enter,exit} and __kvm_guest_{enter,exit} trivial wrappers
around the code in context_tracking.h.  Name the context_tracking.h functions
consistently with what those for kernel<->user switch.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-28 14:15:25 +02:00
James Hogan fb6cec1492 MIPS: KVM: Combine entry trace events into class
Combine the kvm_enter, kvm_reenter and kvm_out trace events into a
single kvm_transition event class to reduce duplication and bloat.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 93258604ab ("MIPS: KVM: Add guest mode switch trace events")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-23 19:17:30 +02:00
Arnd Bergmann 87aeb54f1b kvm: x86: use getboottime64
KVM reads the current boottime value as a struct timespec in order to
calculate the guest wallclock time, resulting in an overflow in 2038
on 32-bit systems.

The data then gets passed as an unsigned 32-bit number to the guest,
and that in turn overflows in 2106.

We cannot do much about the second overflow, which affects both 32-bit
and 64-bit hosts, but we can ensure that they both behave the same
way and don't overflow until 2106, by using getboottime64() to read
a timespec64 value.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-23 19:17:30 +02:00
Ashok Raj c45dcc71b7 KVM: VMX: enable guest access to LMCE related MSRs
On Intel platforms, this patch adds LMCE to KVM MCE supported
capabilities and handles guest access to LMCE related MSRs.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
[Haozhong: macro KVM_MCE_CAP_SUPPORTED => variable kvm_mce_cap_supported
           Only enable LMCE on Intel platform
           Check MSR_IA32_FEATURE_CONTROL when handling guest
             access to MSR_IA32_MCG_EXT_CTL]
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-23 19:17:29 +02:00