Andre Przywara [Tue, 21 Dec 2010 10:12:00 +0000 (11:12 +0100)]
KVM: x86: fix CR8 handling
The handling of CR8 writes in KVM is currently somewhat cumbersome.
This patch makes it look like the other CR register handlers
and fixes a possible issue in VMX, where the RIP would be incremented
despite an injected #GP.
Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Sun, 12 Dec 2010 17:30:55 +0000 (19:30 +0200)]
KVM: MMU: Fix incorrect direct page write protection due to ro host page
If KVM sees a read-only host page, it will map it as read-only to prevent
breaking a COW. However, if the page was part of a large guest page, KVM
incorrectly extends the write protection to the entire large page frame
instead of limiting it to the normal host page.
This results in the instantiation of a new shadow page with read-only access.
If this happens for a MOVS instruction that moves memory between two normal
pages, within a single large page frame, and mapped within the guest as a
large page, and if, in addition, the source operand is not writeable in the
host (perhaps due to KSM), then KVM will instantiate a read-only direct
shadow page, instantiate an spte for the source operand, then instantiate
a new read/write direct shadow page and instantiate an spte for the
destination operand. Since these two sptes are in different shadow pages,
MOVS will never see them at the same time and the guest will not make
progress.
Fix by mapping the direct shadow page read/write, and only marking the
host page read-only.
Joerg Roedel [Tue, 7 Dec 2010 16:15:06 +0000 (17:15 +0100)]
KVM: SVM: Add xsetbv intercept
This patch implements the xsetbv intercept to the AMD part
of KVM. This makes AVX usable in a save way for the guest on
AVX capable AMD hardware.
The patch is tested by using AVX in the guest and host in
parallel and checking for data corruption. I also used the
KVM xsave unit-tests and they all pass.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: MMU: Make the way of accessing lpage_info more generic
Large page information has two elements but one of them, write_count, alone
is accessed by a helper function.
This patch replaces this helper function with more generic one which returns
newly named kvm_lpage_info structure and use it to access the other element
rmap_pde.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
In certain use-cases, we want to allocate guests fixed time slices where idle
guest cycles leave the machine idling. There are many approaches to achieve
this but the most direct is to simply avoid trapping the HLT instruction which
lets the guest directly execute the instruction putting the processor to sleep.
Introduce this as a module-level option for kvm-vmx.ko since if you do this
for one guest, you probably want to do it for all.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 3 Dec 2010 14:25:15 +0000 (15:25 +0100)]
KVM: SVM: Use svm_flush_tlb instead of force_new_asid
This patch replaces all calls to force_new_asid which are
intended to flush the guest-tlb by the more appropriate
function svm_flush_tlb. As a side-effect the force_new_asid
function is removed.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Xiao Guangrong [Tue, 7 Dec 2010 02:48:06 +0000 (10:48 +0800)]
KVM: MMU: rename 'no_apf' to 'prefault'
It's the speculative path if 'no_apf = 1' and we will specially handle this
speculative path in the later patch, so 'prefault' is better to fit the sense.
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 3 Dec 2010 10:45:50 +0000 (11:45 +0100)]
KVM: SVM: Add clean-bit for IOPM_BASE and MSRPM_BASE
This patch adds the clean bit for the physical addresses of
the MSRPM and the IOPM. It does not need to be set in the
code because the only place where these values are changed
is the nested-svm vmrun and vmexit path. These functions
already mark the complete VMCB as dirty.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 3 Dec 2010 10:45:49 +0000 (11:45 +0100)]
KVM: SVM: Add clean-bit for intercetps, tsc-offset and pause filter count
This patch adds the clean-bit for intercepts-vectors, the
TSC offset and the pause-filter count to the appropriate
places. The IO and MSR permission bitmaps are not subject to
this bit.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Thu, 2 Dec 2010 15:55:23 +0000 (17:55 +0200)]
KVM: VMX: Return 0 from a failed VMREAD
If we execute VMREAD during reboot we'll just skip over it. Instead of
returning garbage, return 0, which has a much smaller chance of confusing
the code. Otherwise we risk a flood of debug printk()s which block the
reboot process if a serial console or netconsole is enabled.
Avi Kivity [Thu, 2 Dec 2010 15:52:50 +0000 (17:52 +0200)]
KVM: Don't spin on virt instruction faults during reboot
Since vmx blocks INIT signals, we disable virtualization extensions during
reboot. This leads to virtualization instructions faulting; we trap these
faults and spin while the reboot continues.
Unfortunately spinning on a non-preemptible kernel may block a task that
reboot depends on; this causes the reboot to hang.
Fix by skipping over the instruction and hoping for the best.
Joerg Roedel [Tue, 30 Nov 2010 17:04:00 +0000 (18:04 +0100)]
KVM: SVM: Add manipulation functions for misc intercepts
This patch wraps changes to the misc intercepts of SVM
into seperate functions to abstract nested-svm better and
prepare the implementation of the vmcb-clean-bits feature.
Joerg Roedel [Tue, 30 Nov 2010 17:03:59 +0000 (18:03 +0100)]
KVM: SVM: Add manipulation functions for exception intercepts
This patch wraps changes to the exception intercepts of SVM
into seperate functions to abstract nested-svm better and
prepare the implementation of the vmcb-clean-bits feature.
Joerg Roedel [Tue, 30 Nov 2010 17:03:58 +0000 (18:03 +0100)]
KVM: SVM: Add manipulation functions for DRx intercepts
This patch wraps changes to the DRx intercepts of SVM into
seperate functions to abstract nested-svm better and prepare
the implementation of the vmcb-clean-bits feature.
Roedel, Joerg [Fri, 3 Dec 2010 09:50:51 +0000 (10:50 +0100)]
KVM: SVM: Add manipulation functions for CRx intercepts
This patch wraps changes to the CRx intercepts of SVM into
seperate functions to abstract nested-svm better and prepare
the implementation of the vmcb-clean-bits feature.
Joerg Roedel [Tue, 30 Nov 2010 17:03:56 +0000 (18:03 +0100)]
KVM: SVM: Add function to recalculate intercept masks
This patch adds a function to recalculate the effective
intercepts masks when the vcpu is in guest-mode and either
the host or the guest intercept masks change.
Joerg Roedel [Mon, 29 Nov 2010 16:51:49 +0000 (17:51 +0100)]
KVM: X86: Don't report L2 emulation failures to user-space
This patch prevents that emulation failures which result
from emulating an instruction for an L2-Guest results in
being reported to userspace.
Without this patch a malicious L2-Guest would be able to
kill the L1 by triggering a race-condition between an vmexit
and the instruction emulator.
With this patch the L2 will most likely only kill itself in
this situation.
This patch introduces a generic representation of guest-mode
fpr a vcpu. This currently only exists in the SVM code.
Having this representation generic will help making the
non-svm code aware of nesting when this is necessary.
Avi Kivity [Mon, 29 Nov 2010 14:12:30 +0000 (16:12 +0200)]
KVM: Pull extra page fault information into struct x86_exception
Currently page fault cr2 and nesting infomation are carried outside
the fault data structure. Instead they are placed in the vcpu struct,
which results in confusion as global variables are manipulated instead
of passing parameters.
Fix this issue by adding address and nested fields to struct x86_exception,
so this struct can carry all information associated with a fault.
Xiao Guangrong [Tue, 23 Nov 2010 03:13:00 +0000 (11:13 +0800)]
KVM: MMU: delay flush all tlbs on sync_page path
Quote from Avi:
| I don't think we need to flush immediately; set a "tlb dirty" bit somewhere
| that is cleareded when we flush the tlb. kvm_mmu_notifier_invalidate_page()
| can consult the bit and force a flush if set.
Avi Kivity [Thu, 18 Nov 2010 11:09:54 +0000 (13:09 +0200)]
KVM: Add instruction-set-specific exit qualifications to kvm_exit trace
The exit reason alone is insufficient to understand exactly why an exit
occured; add ISA-specific trace parameters for additional information.
Because fetching these parameters is expensive on vmx, and because these
parameters are fetched even if tracing is disabled, we fetch the
parameters via a callback instead of as traditional trace arguments.
Store irq routing table pointer in the irqfd object,
and use that to inject MSI directly without bouncing out to
a kernel thread.
While we touch this structure, rearrange irqfd fields to make fastpath
better packed for better cache utilization.
This also adds some comments about locking rules and rcu usage in code.
Some notes on the design:
- Use pointer into the rt instead of copying an entry,
to make it possible to use rcu, thus side-stepping
locking complexities. We also save some memory this way.
- Old workqueue code is still used for level irqs.
I don't think we DTRT with level anyway, however,
it seems easier to keep the code around as
it has been thought through and debugged, and fix level later than
rip out and re-instate it later.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Acked-by: Gregory Haskins <ghaskins@novell.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Thu, 18 Nov 2010 11:12:52 +0000 (13:12 +0200)]
KVM: VMX: Fold __vmx_vcpu_run() into vmx_vcpu_run()
cea15c2 ("KVM: Move KVM context switch into own function") split vmx_vcpu_run()
to prevent multiple copies of the context switch from being generated (causing
problems due to a label). This patch folds them back together again and adds
the __noclone attribute to prevent the label from being duplicated.
Avi Kivity [Wed, 17 Nov 2010 13:28:21 +0000 (15:28 +0200)]
KVM: x86 emulator: preserve an operand's segment identity
Currently the x86 emulator converts the segment register associated with
an operand into a segment base which is added into the operand address.
This loss of information results in us not doing segment limit checks properly.
Replace struct operand's addr.mem field by a segmented_address structure
which holds both the effetive address and segment. This will allow us to
do the limit check at the point of access.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Shane Wang [Wed, 17 Nov 2010 03:40:17 +0000 (11:40 +0800)]
KVM: VMX: Inform user about INTEL_TXT dependency
Inform user to either disable TXT in the BIOS or do TXT launch
with tboot before enabling KVM since some BIOSes do not set
FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX bit when TXT is enabled.
Signed-off-by: Shane Wang <shane.wang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Takuya Yoshikawa [Tue, 16 Nov 2010 08:37:41 +0000 (17:37 +0900)]
KVM: rename hardware_[dis|en]able() to *_nolock() and add locking wrappers
The naming convension of hardware_[dis|en]able family is little bit confusing
because only hardware_[dis|en]able_all are using _nolock suffix.
Renaming current hardware_[dis|en]able() to *_nolock() and using
hardware_[dis|en]able() as wrapper functions which take kvm_lock for them
reduces extra confusion.
Jan Kiszka [Tue, 16 Nov 2010 21:30:07 +0000 (22:30 +0100)]
KVM: Document device assigment API
Adds API documentation for KVM_[DE]ASSIGN_PCI_DEVICE,
KVM_[DE]ASSIGN_DEV_IRQ, KVM_SET_GSI_ROUTING, KVM_ASSIGN_SET_MSIX_NR, and
KVM_ASSIGN_SET_MSIX_ENTRY.
Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Tue, 16 Nov 2010 21:30:06 +0000 (22:30 +0100)]
KVM: Clean up kvm_vm_ioctl_assigned_device
Any arch not supporting device assigment will also not build
assigned-dev.c. So testing for KVM_CAP_DEVICE_DEASSIGNMENT is pointless.
KVM_CAP_ASSIGN_DEV_IRQ is unconditinally set. Moreover, add a default
case for dispatching the ioctl.
Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Tue, 16 Nov 2010 21:30:05 +0000 (22:30 +0100)]
KVM: Save/restore state of assigned PCI device
The guest may change states that pci_reset_function does not touch. So
we better save/restore the assigned device across guest usage.
Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Tue, 16 Nov 2010 21:30:04 +0000 (22:30 +0100)]
KVM: Refactor IRQ names of assigned devices
Cosmetic change, but it helps to correlate IRQs with PCI devices.
Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Tue, 16 Nov 2010 21:30:03 +0000 (22:30 +0100)]
KVM: Switch assigned device IRQ forwarding to threaded handler
This improves the IRQ forwarding for assigned devices: By using the
kernel's threaded IRQ scheme, we can get rid of the latency-prone work
queue and simplify the code in the same run.
Moreover, we no longer have to hold assigned_dev_lock while raising the
guest IRQ, which can be a lenghty operation as we may have to iterate
over all VCPUs. The lock is now only used for synchronizing masking vs.
unmasking of INTx-type IRQs, thus is renames to intx_lock.
Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Jan Kiszka [Tue, 16 Nov 2010 21:30:02 +0000 (22:30 +0100)]
KVM: Clear assigned guest IRQ on release
When we deassign a guest IRQ, clear the potentially asserted guest line.
There might be no chance for the guest to do this, specifically if we
switch from INTx to MSI mode.
Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Avi Kivity [Tue, 9 Nov 2010 14:15:42 +0000 (16:15 +0200)]
KVM: SVM: Replace svm_has() by standard Linux cpuid accessors
Instead of querying cpuid directly, use the Linux accessors (boot_cpu_has,
etc.). This allows the things like the clearcpuid kernel command line to
work (when it's fixed wrt scattered cpuid bits).
Jan Kiszka [Tue, 9 Nov 2010 16:02:49 +0000 (17:02 +0100)]
KVM: Clean up vm creation and release
IA64 support forces us to abstract the allocation of the kvm structure.
But instead of mixing this up with arch-specific initialization and
doing the same on destruction, split both steps. This allows to move
generic destruction calls into generic code.
It also fixes error clean-up on failures of kvm_create_vm for IA64.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Mon, 1 Nov 2010 21:20:48 +0000 (23:20 +0200)]
KVM: VMX: Disallow NMI while blocked by STI
While not mandated by the spec, Linux relies on NMI being blocked by an
IF-enabling STI. VMX also refuses to enter a guest in this state, at
least on some implementations.
Disallow NMI while blocked by STI by checking for the condition, and
requesting an interrupt window exit if it occurs.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Xiao Guangrong [Mon, 1 Nov 2010 09:03:44 +0000 (17:03 +0800)]
KVM: fix the race while wakeup all pv guest
In kvm_async_pf_wakeup_all(), we add a dummy apf to vcpu->async_pf.done
without holding vcpu->async_pf.lock, it will break if we are handling apfs
at this time.
Also use 'list_empty_careful()' instead of 'list_empty()'
Xiao Guangrong [Mon, 1 Nov 2010 09:01:28 +0000 (17:01 +0800)]
KVM: avoid unnecessary wait for a async pf
In current code, it checks async pf completion out of the wait context,
like this:
if (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE &&
!vcpu->arch.apf.halted)
r = vcpu_enter_guest(vcpu);
else {
......
kvm_vcpu_block(vcpu)
^- waiting until 'async_pf.done' is not empty
}
kvm_check_async_pf_completion(vcpu)
^- delete list from async_pf.done
So, if we check aysnc pf completion first, it can be blocked at
kvm_vcpu_block
Fixed by mark the vcpu is unhalted in kvm_check_async_pf_completion()
path
Gleb Natapov [Mon, 1 Nov 2010 13:35:01 +0000 (15:35 +0200)]
KVM: handle exit due to INVD in VMX
Currently the exit is unhandled, so guest halts with error if it tries
to execute INVD instruction. Call into emulator when INVD instruction
is executed by a guest instead. This instruction is not needed by ordinary
guests, but firmware (like OpenBIOS) use it and fail.
Jan Kiszka [Mon, 1 Nov 2010 13:01:29 +0000 (14:01 +0100)]
KVM: x86: Avoid issuing wbinvd twice
Micro optimization to avoid calling wbinvd twice on the CPU that has to
emulate it. As we might be preempted between smp_call_function_many and
the local wbinvd, the cache might be filled again so that real work
could be done uselessly.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Heiko Carstens [Wed, 27 Oct 2010 15:22:10 +0000 (17:22 +0200)]
KVM: get rid of warning within kvm_dev_ioctl_create_vm
Fixes this:
CC arch/s390/kvm/../../../virt/kvm/kvm_main.o
arch/s390/kvm/../../../virt/kvm/kvm_main.c: In function 'kvm_dev_ioctl_create_vm':
arch/s390/kvm/../../../virt/kvm/kvm_main.c:1828:10: warning: unused variable 'r'
Heiko Carstens [Wed, 27 Oct 2010 15:21:21 +0000 (17:21 +0200)]
KVM: add cast within kvm_clear_guest_page to fix warning
Fixes this:
CC arch/s390/kvm/../../../virt/kvm/kvm_main.o
arch/s390/kvm/../../../virt/kvm/kvm_main.c: In function 'kvm_clear_guest_page':
arch/s390/kvm/../../../virt/kvm/kvm_main.c:1224:2: warning: passing argument 3 of 'kvm_write_guest_page' makes pointer from integer without a cast
arch/s390/kvm/../../../virt/kvm/kvm_main.c:1185:5: note: expected 'const void *' but argument is of type 'long unsigned int'
Takuya Yoshikawa [Wed, 27 Oct 2010 09:23:54 +0000 (18:23 +0900)]
KVM: pre-allocate one more dirty bitmap to avoid vmalloc()
Currently x86's kvm_vm_ioctl_get_dirty_log() needs to allocate a bitmap by
vmalloc() which will be used in the next logging and this has been causing
bad effect to VGA and live-migration: vmalloc() consumes extra systime,
triggers tlb flush, etc.
This patch resolves this issue by pre-allocating one more bitmap and switching
between two bitmaps during dirty logging.
Performance improvement:
I measured performance for the case of VGA update by trace-cmd.
The result was 1.5 times faster than the original one.
In the case of live migration, the improvement ratio depends on the workload
and the guest memory size. In general, the larger the memory size is the more
benefits we get.
Note:
This does not change other architectures's logic but the allocation size
becomes twice. This will increase the actual memory consumption only when
the new size changes the number of pages allocated by vmalloc().
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Takuya Yoshikawa [Wed, 27 Oct 2010 09:22:19 +0000 (18:22 +0900)]
KVM: introduce wrapper functions for creating/destroying dirty bitmaps
This makes it easy to change the way of allocating/freeing dirty bitmaps.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
projects / mirror_ubuntu-artful-kernel.git / log