If two conditions apply:
- no bits outside TS and EM differ between the host and guest cr0
- the fpu is active
then we can activate the selective cr0 write intercept and drop the
unconditional cr0 read and write intercept, and allow the guest to run
with the host fpu state. This reduces cr0 exits due to guest fpu management
while the guest fpu is loaded.
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently we don't intercept cr0 at all when npt is enabled. This improves
performance but requires us to activate the fpu at all times.
Remove this behaviour in preparation for adding selective cr0 intercepts.
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
init_vmcb() sets up the intercepts as if the fpu is active, so initialize it
there. This avoids an INIT from setting up intercepts inconsistent with
fpu_active.
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If the guest fpu is loaded, there is nothing interesing about cr0.ts; let
the guest play with it as it will. This makes context switches between fpu
intensive guest processes faster, as we won't trap the clts and cr0 write
instructions.
[marcelo: fix cr0 read shadow update on fpu deactivation; kills F8 install]
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Defer fpu deactivation as much as possible - if the guest fpu is loaded, keep
it loaded until the next heavyweight exit (where we are forced to unload it).
This reduces unnecessary exits.
We also defer fpu activation on clts; while clts signals the intent to use the
fpu, we can't be sure the guest will actually use it.
Signed-off-by: Avi Kivity <avi@redhat.com>
Since we'd like to allow the guest to own a few bits of cr0 at times, we need
to know when we access those bits.
Signed-off-by: Avi Kivity <avi@redhat.com>
Then the callback can provide the maximum supported large page level, which
is more flexible.
Also move the gb page support into x86_64 specific.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Some exit reasons missed their strings; fill out the table.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Use two steps for memslot deletion: mark the slot invalid (which stops
instantiation of new shadow pages for that slot, but allows destruction),
then instantiate the new empty slot.
Also simplifies kvm_handle_hva locking.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Have a pointer to an allocated region inside struct kvm.
[alex: fix ppc book 3s]
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
The tsc_offset adjustment in svm_vcpu_load is executed
unconditionally even if Linux considers the host tsc as
stable. This causes a Linux guest detecting an unstable tsc
in any case.
This patch removes the tsc_offset adjustment if the host tsc
is stable. The guest will now get the benefit of a stable
tsc too.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Before enabling, execution of "rdtscp" in guest would result in #UD.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Sometime, we need to adjust some state in order to reflect guest CPUID
setting, e.g. if we don't expose rdtscp to guest, we won't want to enable
it on hardware. cpuid_update() is introduced for this purpose.
Also export kvm_find_cpuid_entry() for later use.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
shared_msr_global saved host value of relevant MSRs, but it have an
assumption that all MSRs it tracked shared the value across the different
CPUs. It's not true with some MSRs, e.g. MSR_TSC_AUX.
Extend it to per CPU to provide the support of MSR_TSC_AUX, and more
alike MSRs.
Notice now the shared_msr_global still have one assumption: it can only deal
with the MSRs that won't change in host after KVM module loaded.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
ept_update_paging_mode_cr4() accesses vcpu->arch.cr4 directly, which usually
needs to be accessed via kvm_read_cr4(). In this case, we can't, since cr4
is in the process of being updated. Instead of adding inane comments, fold
the function into its caller (vmx_set_cr4), so it can use the not-yet-committed
cr4 directly.
Signed-off-by: Avi Kivity <avi@redhat.com>
We make no use of cr4.pge if ept is enabled, but the guest does (to flush
global mappings, as with vmap()), so give the guest ownership of this bit.
Signed-off-by: Avi Kivity <avi@redhat.com>
Instead of specifying the bits which we want to trap on, specify the bits
which we allow the guest to change transparently. This is safer wrt future
changes to cr4.
Signed-off-by: Avi Kivity <avi@redhat.com>
Some bits of cr4 can be owned by the guest on vmx, so when we read them,
we copy them to the vcpu structure. In preparation for making the set of
guest-owned bits dynamic, use helpers to access these bits so we don't need
to know where the bit resides.
No changes to svm since all bits are host-owned there.
Signed-off-by: Avi Kivity <avi@redhat.com>
We don't support these instructions, but guest can execute them even if the
feature('monitor') haven't been exposed in CPUID. So we would trap and inject
a #UD if guest try this way.
Cc: stable@kernel.org
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
In the past we've had errors of single-bit in the other two cases; the
printk() may confirm it for the third case (many->many).
Signed-off-by: Avi Kivity <avi@redhat.com>
Windows 2003 uses task switch to triple fault and reboot (the other
exception being reserved pdptrs bits).
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Move Double-Fault generation logic out of page fault
exception generating function to cover more generic case.
Signed-off-by: Eddie Dong <eddie.dong@intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Current kvm wallclock does not consider the total_sleep_time which could cause
wrong wallclock in guest after host suspend/resume. This patch solve
this issue by counting total_sleep_time to get the correct host boot time.
Cc: stable@kernel.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
In function kvm_arch_vcpu_init(), if the memory malloc for
vcpu->arch.mce_banks is fail, it does not free the memory
of lapic date. This patch fixed it.
Cc: stable@kernel.org
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
vcpu->arch.mce_banks is malloc in kvm_arch_vcpu_init(), but
never free in any place, this may cause memory leak. So this
patch fixed to free it in kvm_arch_vcpu_uninit().
Cc: stable@kernel.org
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Exit the guest pagetable walk loop if reading gpte failed. Otherwise its
possible to enter an endless loop processing the previous present pte.
Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
When found a error hva, should not return PAGE_SIZE but the level...
Also clean up the coding style of the following loop.
Cc: stable@kernel.org
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
When we queue an interrupt to the local apic, we set the IRR before the TMR.
The vcpu can pick up the IRR and inject the interrupt before setting the TMR,
and perhaps even EOI it, causing incorrect behaviour.
The race is really insignificant since it can only occur on the first
interrupt (usually following interrupts will not change TMR), but it's better
closed than open.
Fixed by reordering setting the TMR vs IRR.
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
User space may not want to overwrite asynchronously changing VCPU event
states on write-back. So allow to skip nmi.pending and sipi_vector by
setting corresponding bits in the flags field of kvm_vcpu_events.
[avi: advertise the bits in KVM_GET_VCPU_EVENTS]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The vcpus are initialized with irr_pending set to false, but
loading the LAPIC registers with pending IRR fails to reset
the irr_pending variable.
Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The invlpg prefault optimization breaks Windows 2008 R2 occasionally.
The visible effect is that the invlpg handler instantiates a pte which
is, microseconds later, written with a different gfn by another vcpu.
The OS could have other mechanisms to prevent a present translation from
being used, which the hypervisor is unaware of.
While the documentation states that the cpu is at liberty to prefetch tlb
entries, it looks like this is not heeded, so remove tlb prefetch from
invlpg.
Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
m68k: rename global variable vmalloc_end to m68k_vmalloc_end
percpu: add missing per_cpu_ptr_to_phys() definition for UP
percpu: Fix kdump failure if booted with percpu_alloc=page
percpu: make misc percpu symbols unique
percpu: make percpu symbols in ia64 unique
percpu: make percpu symbols in powerpc unique
percpu: make percpu symbols in x86 unique
percpu: make percpu symbols in xen unique
percpu: make percpu symbols in cpufreq unique
percpu: make percpu symbols in oprofile unique
percpu: make percpu symbols in tracer unique
percpu: make percpu symbols under kernel/ and mm/ unique
percpu: remove some sparse warnings
percpu: make alloc_percpu() handle array types
vmalloc: fix use of non-existent percpu variable in put_cpu_var()
this_cpu: Use this_cpu_xx in trace_functions_graph.c
this_cpu: Use this_cpu_xx for ftrace
this_cpu: Use this_cpu_xx in nmi handling
this_cpu: Use this_cpu operations in RCU
this_cpu: Use this_cpu ops for VM statistics
...
Fix up trivial (famous last words) global per-cpu naming conflicts in
arch/x86/kvm/svm.c
mm/slab.c
* 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (84 commits)
KVM: VMX: Fix comparison of guest efer with stale host value
KVM: s390: Fix prefix register checking in arch/s390/kvm/sigp.c
KVM: Drop user return notifier when disabling virtualization on a cpu
KVM: VMX: Disable unrestricted guest when EPT disabled
KVM: x86 emulator: limit instructions to 15 bytes
KVM: s390: Make psw available on all exits, not just a subset
KVM: x86: Add KVM_GET/SET_VCPU_EVENTS
KVM: VMX: Report unexpected simultaneous exceptions as internal errors
KVM: Allow internal errors reported to userspace to carry extra data
KVM: Reorder IOCTLs in main kvm.h
KVM: x86: Polish exception injection via KVM_SET_GUEST_DEBUG
KVM: only clear irq_source_id if irqchip is present
KVM: x86: disallow KVM_{SET,GET}_LAPIC without allocated in-kernel lapic
KVM: x86: disallow multiple KVM_CREATE_IRQCHIP
KVM: VMX: Remove vmx->msr_offset_efer
KVM: MMU: update invlpg handler comment
KVM: VMX: move CR3/PDPTR update to vmx_set_cr3
KVM: remove duplicated task_switch check
KVM: powerpc: Fix BUILD_BUG_ON condition
KVM: VMX: Use shared msr infrastructure
...
Trivial conflicts due to new Kconfig options in arch/Kconfig and kernel/Makefile
