Matt T. Yourst notes that kvm_arch_vcpu_ioctl_set_sregs lacks validity
checking for the new cr3 value:
"Userspace callers of KVM_SET_SREGS can pass a bogus value of cr3 to
the kernel. This will trigger a NULL pointer access in gfn_to_rmap()
when userspace next tries to call KVM_RUN on the affected VCPU and kvm
attempts to activate the new non-existent page table root.
This happens since kvm only validates that cr3 points to a valid guest
physical memory page when code *inside* the guest sets cr3. However, kvm
currently trusts the userspace caller (e.g. QEMU) on the host machine to
always supply a valid page table root, rather than properly validating
it along with the rest of the reloaded guest state."
http://sourceforge.net/tracker/?func=detail&atid=893831&aid=2687641&group_id=180599
Check for a valid cr3 address in kvm_arch_vcpu_ioctl_set_sregs, triple
fault in case of failure.
Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Reorder locking to avoid holding the slots_lock when entering
the guest.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by : Xiantao Zhang<xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If a task switch was initiated because off a task gate in IDT and IDT
was accessed because of an external even the instruction should not
be skipped.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
In the new mode instruction is decoded, but not executed. The EIP
is moved to point after the instruction.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Extend "Source operand type" opcode description field to 4 bites
to accommodate new option.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Two things needed fixing: 1) g++ does not allow a named structure type
within an anonymous union and 2) Avoid name clash between two padding
fields within the same struct by giving them different names as is
done elsewhere in the header.
Signed-off-by: Nathan Binkert <nate@binkert.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
Commit 46ee278652f4cbd51013471b64c7897ba9bcd1b1 causes Solaris 10
to hang on boot.
Assuming that PIT counter reads should return 0 for an expired timer
is wrong: when it is active, the counter never stops (see comment on
__kpit_elapsed).
Also arm a one shot timer for mode 0.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Since kvm-intel modue can't be built-in, make kvm depend on
CONFIG_MODULES.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The length of pushed on to the stack return address depends on operand
size not address size.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
1. It's related to a Linux kernel bug which fixed by Ingo on
07a66d7c53. The original code exists for quite a
long time, and it would convert a PDE for large page into a normal PDE. But it
fail to fit normal PDE well. With the code before Ingo's fix, the kernel would
fall reserved bit checking with bit 8 - the remaining global bit of PTE. So the
kernel would receive a double-fault.
2. After discussion, we decide to discard PDE bit 7-8 reserved checking for now.
For this marked as reserved in SDM, but didn't checked by the processor in
fact...
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There is no need to skip instruction if the reason for a task switch
is a task gate in IDT and access to it is caused by an external even.
The problem is currently solved only for VMX since there is no reliable
way to skip an instruction in SVM. We should emulate it instead.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
We will need it later in task_switch().
Code in handle_exception() is dead. is_external_interrupt(vect_info)
will always be false since idt_vectoring_info is zeroed in
vmx_complete_interrupts().
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
...with a more straightforward switch().
Also fix a bug when NMI could be dropped on exit. Although this should
never happen in practice, since NMIs can only be injected, never triggered
internally by the guest like exceptions.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Bit 12 is undefined in any of the following cases:
If the VM exit sets the valid bit in the IDT-vectoring information field.
If the VM exit is due to a double fault.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The testing of feature is too early now, before vmcs_config complete initialization.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
A pte that is shadowed when the guest EFER.NXE=1 is not valid when
EFER.NXE=0; if bit 63 is set, the pte should cause a fault, and since the
shadow EFER always has NX enabled, this won't happen.
Fix by using a different shadow page table for different EFER.NXE bits. This
allows vcpus to run correctly with different values of EFER.NXE, and for
transitions on this bit to be handled correctly without requiring a full
flush.
Signed-off-by: Avi Kivity <avi@redhat.com>
Detect, indicate, and propagate page faults where reserved bits are set.
Take care to handle the different paging modes, each of which has different
sets of reserved bits.
[avi: fix pte reserved bits for efer.nxe=0]
Signed-off-by: Eddie Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently, the interrupt enable bit is cleared when in
the vmm. This patch sets the bit and the external interrupts can
be dealt with when in the vmm. This improves the I/O performance.
Signed-off-by: Yang Zhang <yang.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The original one is for the code before refactoring.
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
EXIT_QUALIFICATION and GUEST_LINEAR_ADDRESS are natural width, not 64-bit.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
kvm_vcpu_block() unhalts vpu on an interrupt/timer without checking
if interrupt window is actually opened.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently timer events are processed before entering guest mode. Move it
to main vcpu event loop since timer events should be processed even while
vcpu is halted. Timer may cause interrupt/nmi to be injected and only then
vcpu will be unhalted.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The prioritized bit vector manipulation functions are useful in both vmx and
svm.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
We ignore writes to the performance counters and performance event
selector registers already. Kaspersky antivirus reads the eventsel
MSR causing it to crash with the current behaviour.
Return 0 as data when the eventsel registers are read to stop the
crash.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
free_mmu_pages() should only undo what alloc_mmu_pages() does.
Free mmu pages from the generic VM destruction function, kvm_destroy_vm().
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
After discussion with Marcelo, we decided to rework device assignment framework
together. The old problems are kernel logic is unnecessary complex. So Marcelo
suggest to split it into a more elegant way:
1. Split host IRQ assign and guest IRQ assign. And userspace determine the
combination. Also discard msi2intx parameter, userspace can specific
KVM_DEV_IRQ_HOST_MSI | KVM_DEV_IRQ_GUEST_INTX in assigned_irq->flags to
enable MSI to INTx convertion.
2. Split assign IRQ and deassign IRQ. Import two new ioctls:
KVM_ASSIGN_DEV_IRQ and KVM_DEASSIGN_DEV_IRQ.
This patch also fixed the reversed _IOR vs _IOW in definition(by deprecated the
old interface).
[avi: replace homemade bitcount() by hweight_long()]
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Fix this sparse warnings:
arch/x86/kvm/lapic.c:916:22: warning: symbol 'lapic_timer_ops' was not declared. Should it be static?
arch/x86/kvm/i8254.c:268:22: warning: symbol 'kpit_ops' was not declared. Should it be static?
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>