This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write
functions. in_range now becomes unused so it is removed from device ops in
favor of read/write callbacks performing range checks internally.

This allows aliasing (mostly for in-kernel virtio), as well as better error
handling by making it possible to pass errors up to userspace.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Use slots_lock to protect device list on the bus.  slots_lock is already
taken for read everywhere, so we only need to take it for write when
registering devices.  This is in preparation to removing in_range and
kvm->lock around it.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

switch pit creation to slots_lock. slots_lock is already taken for read
everywhere, so we only need to take it for write when creating pit.
This is in preparation to removing in_range and kvm->lock around it.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

switch coalesced mmio slots_lock.  slots_lock is already taken for read
everywhere, so we only need to take it for write when changing zones.
This is in preparation to removing in_range and kvm->lock around it.

[avi: fix build]
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

slots_lock is taken everywhere when device ops are called.
Document this as we will use this to rework locking for io.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Change kvm_vcpu_is_bsp to use vcpu_id instead of bsp_vcpu pointer, which
is only initialized at the end of kvm_vm_ioctl_create_vcpu.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Return EOPNOTSUPP for KVM_TRACE_ENABLE/PAUSE/DISABLE ioctls.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

[avi: make it build]
[avi: fold trace-arch.h into trace.h]

CC: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

KVM will inject a #GP into the guest if that tries to access unhandled
MSRs. This will crash many guests. Although it would be the correct
way to actually handle these MSRs, we introduce a runtime switchable
module param called "ignore_msrs" (defaults to 0). If this is Y, unknown
MSR reads will return 0, while MSR writes are simply dropped. In both cases
we print a message to dmesg to inform the user about that.

You can change the behaviour at any time by saying:

 # echo 1 > /sys/modules/kvm/parameters/ignore_msrs
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

If the Linux kernel detects an C1E capable AMD processor (K8 RevF and
higher), it will access a certain MSR on every attempt to go to halt.
Explicitly handle this read and return 0 to let KVM run a Linux guest
with the native AMD host CPU propagated to the guest.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Linux tries to disable the flush filter on all AMD K8 CPUs. Since KVM
does not handle the needed MSR, the injected #GP will panic the Linux
kernel. Ignore setting of the HWCR.FFDIS bit in this MSR to let Linux
boot with an AMD K8 family guest CPU.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Correct missing locking in a few places in x86's vm_ioctl handling path.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

[avi: fix build on non-x86]
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This function is required by KVM.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Since
commit 854b5338196b1175706e99d63be43a4f8d8ab607
Author: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
    KVM: s390: streamline memslot handling

s390 uses the values of the memslot instead of doing everything in the arch
ioctl handler of the KVM_SET_USER_MEMORY_REGION. Unfortunately we missed to
set the userspace_addr of our memslot due to our s390 ifdef in
__kvm_set_memory_region.
Old s390 userspace launchers did not notice, since they started the guest at
userspace address 0.
Because of CONFIG_DEFAULT_MMAP_MIN_ADDR we now put the guest at 1M userspace,
which does not work. This patch makes sure that new.userspace_addr is set
on s390.
This fix should go in quickly. Nevertheless, looking at the code we should
clean up that ifdef in the long term. Any kernel janitors?
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Handle #UD intercept of the sysexit instruction in 64bit mode returning to
32bit compat mode on an AMD host.
Setup the segment descriptors for CS and SS and the EIP/ESP registers
according to the manual.
Signed-off-by: NChristoph Egger <christoph.egger@amd.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Handle #UD intercept of the sysenter instruction in 32bit compat mode on
an AMD host.
Setup the segment descriptors for CS and SS and the EIP/ESP registers
according to the manual.
Signed-off-by: NChristoph Egger <christoph.egger@amd.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Handle #UD intercept of the syscall instruction in 32bit compat mode on
an Intel host.
Setup the segment descriptors for CS and SS and the EIP/ESP registers
according to the manual. Save the RIP and EFLAGS to the correct registers.

[avi: fix build on i386 due to missing R11]
Signed-off-by: NChristoph Egger <christoph.egger@amd.com>
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Add the flags needed for syscall, sysenter and sysexit to the opcode table.
Catch (but for now ignore) the opcodes in the emulation switch/case.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NChristoph Egger <christoph.egger@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NChristoph Egger <christoph.egger@amd.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Add the opcodes for syscall, sysenter and sysexit to the list of instructions
handled by the undefined opcode handler.
Signed-off-by: NChristoph Egger <christoph.egger@amd.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This allows use of the powerful ftrace infrastructure.

See Documentation/trace/ for usage information.

[avi, stephen: various build fixes]
[sheng: fix control register breakage]
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

While trying to get Hyper-V running, I realized that the interrupt injection
mechanisms that are in place right now are not 100% correct.

This patch makes nested SVM's interrupt injection behave more like on a
real machine.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

SVM adds another way to do INVLPG by ASID which Hyper-V makes use of,
so let's implement it!

For now we just do the same thing invlpg does, as asid switching
means we flush the mmu anyways. That might change one day though.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Hyper-V uses some MSRs, some of which are actually reserved for BIOS usage.

But let's be nice today and have it its way, because otherwise it fails
terribly.

[jaswinder: fix build for linux-next changes]
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Hyper-V accesses MSR_IGNNE while running under KVM.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The host never reads cr2 in process context, so are free to clobber it.  The
vmx code does this, so we can safely remove the save/restore code.
Signed-off-by: NAvi Kivity <avi@redhat.com>

cr2 changes only rarely, and writing it is expensive.  Avoid the costly cr2
writes by checking if it does not already hold the desired value.

Shaves 70 cycles off the vmexit latency.
Signed-off-by: NAvi Kivity <avi@redhat.com>

The current code tries to optimize the setting of
KVM_REQ_PENDING_TIMER but used atomic_inc_and_test - which always
returns true unless pending had the invalid value of -1 on entry. This
patch drops the test part preserving the original semantic but
expressing it less confusingly.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Minor issue that likely had no practical relevance: the kvm timer
function so far incremented the pending counter and then may reset it
again to 1 in case reinjection was disabled. This opened a small racy
window with the corresponding VCPU loop that may have happened to run
on another (real) CPU and already consumed the value.

Fix it by skipping the incrementation in case pending is already > 0.
This opens a different race windows, but may only rarely cause lost
events in case we do not care about them anyway (!reinject).
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Most of the time IRR is empty, so instead of scanning the whole IRR on
each VM entry keep a variable that tells us if IRR is not empty. IRR
will have to be scanned twice on each IRQ delivery, but this is much
more rare than VM entry.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Replace previous exception with a new one in a hope that instruction
re-execution will regenerate lost exception.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Disable usage of 2M pages if VMX_EPT_2MB_PAGE_BIT (bit 16) is clear
in MSR_IA32_VMX_EPT_VPID_CAP and EPT is enabled.

[avi: s/largepages_disabled/largepages_enabled/ to avoid negative logic]
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Handler for EPT misconfiguration which checks for valid state
in the shadow pagetables, printing the spte on each level.

The separate WARN_ONs are useful for kerneloops.org.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Required by EPT misconfiguration handler.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

This way there is no need to add explicit checks in every
for_each_shadow_entry user.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Required for EPT misconfiguration handler.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The performance counter MSRs are different for AMD and Intel CPUs and they
are chosen mainly by the CPUID vendor string. This patch catches writes to
all addresses (regardless of VMX/SVM path) and handles them in the generic
MSR handler routine. Writing a 0 into the event select register is something
we perfectly emulate ;-), so don't print out a warning to dmesg in this
case.
This fixes booting a 64bit Windows guest with an AMD CPUID on an Intel host.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Make the audit code aware of largepages.
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

- Fail early in case gfn_to_pfn returns is_error_pfn.
- For the pre pte write case, avoid spurious "gva is valid but spte is notrap"
  messages (the emulation code does the guest write first, so this particular
  case is OK).
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>