Commit Graph

852 Commits

Author SHA1 Message Date
Joerg Roedel
7fcdb5103d KVM: SVM: reorganize svm_interrupt_allowed
This patch reorganizes the logic in svm_interrupt_allowed to
make it better to read. This is important because the logic
is a lot more complicated with Nested SVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-12-03 09:32:11 +02:00
Huang Weiyi
bfc33beaed KVM: remove duplicated #include
Remove duplicated #include('s) in
  arch/x86/kvm/lapic.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-12-03 09:32:10 +02:00
Alexander Graf
10474ae894 KVM: Activate Virtualization On Demand
X86 CPUs need to have some magic happening to enable the virtualization
extensions on them. This magic can result in unpleasant results for
users, like blocking other VMMs from working (vmx) or using invalid TLB
entries (svm).

Currently KVM activates virtualization when the respective kernel module
is loaded. This blocks us from autoloading KVM modules without breaking
other VMMs.

To circumvent this problem at least a bit, this patch introduces on
demand activation of virtualization. This means, that instead
virtualization is enabled on creation of the first virtual machine
and disabled on destruction of the last one.

So using this, KVM can be easily autoloaded, while keeping other
hypervisors usable.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:10 +02:00
Marcelo Tosatti
e8b3433a5c KVM: SVM: remove needless mmap_sem acquision from nested_svm_map
nested_svm_map unnecessarily takes mmap_sem around gfn_to_page, since
gfn_to_page / get_user_pages are responsible for it.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:10 +02:00
Mohammed Gamal
80ced186d1 KVM: VMX: Enhance invalid guest state emulation
- Change returned handle_invalid_guest_state() to return relevant exit codes
- Move triggering the emulation from vmx_vcpu_run() to vmx_handle_exit()
- Return to userspace instead of repeatedly trying to emulate instructions that have already failed

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-12-03 09:32:09 +02:00
Mohammed Gamal
abcf14b560 KVM: x86 emulator: Add pusha and popa instructions
This adds pusha and popa instructions (opcodes 0x60-0x61), this enables booting
MINIX with invalid guest state emulation on.

[marcelo: remove unused variable]

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:09 +02:00
Mohammed Gamal
94677e61fd KVM: x86 emulator: Add missing decoder flags for 'or' instructions
Add missing decoder flags for or instructions (0xc-0xd).

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:09 +02:00
Avi Kivity
bfd99ff5d4 KVM: Move assigned device code to own file
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:09 +02:00
Avi Kivity
367e1319b2 KVM: Return -ENOTTY on unrecognized ioctls
Not the incorrect -EINVAL.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:08 +02:00
Gleb Natapov
680b3648ba KVM: Drop kvm->irq_lock lock from irq injection path
The only thing it protects now is interrupt injection into lapic and
this can work lockless. Even now with kvm->irq_lock in place access
to lapic is not entirely serialized since vcpu access doesn't take
kvm->irq_lock.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:08 +02:00
Gleb Natapov
eba0226bdf KVM: Move IO APIC to its own lock
The allows removal of irq_lock from the injection path.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:08 +02:00
Gleb Natapov
1a6e4a8c27 KVM: Move irq sharing information to irqchip level
This removes assumptions that max GSIs is smaller than number of pins.
Sharing is tracked on pin level not GSI level.

[avi: no PIC on ia64]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:06 +02:00
Gleb Natapov
79c727d437 KVM: Call pic_clear_isr() on pic reset to reuse logic there
Also move call of ack notifiers after pic state change.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:06 +02:00
Avi Kivity
851ba6922a KVM: Don't pass kvm_run arguments
They're just copies of vcpu->run, which is readily accessible.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:06 +02:00
Mohammed Gamal
d8769fedd4 KVM: x86 emulator: Introduce No64 decode option
Introduces a new decode option "No64", which is used for instructions that are
invalid in long mode.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:05 +02:00
Mohammed Gamal
0934ac9d13 KVM: x86 emulator: Add 'push/pop sreg' instructions
[avi: avoid buffer overflow]

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:05 +02:00
Ingo Molnar
96200591a3 Merge branch 'tracing/hw-breakpoints' into perf/core
Conflicts:
	arch/x86/kernel/kprobes.c
	kernel/trace/Makefile

Merge reason: hw-breakpoints perf integration is looking
              good in testing and in reviews, plus conflicts
              are mounting up - so merge & resolve.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:07:23 +01:00
Frederic Weisbecker
59d8eb53ea hw-breakpoints: Wrap in the KVM breakpoint active state check
Wrap in the cpu dr7 check that tells if we have active
breakpoints that need to be restored in the cpu.

This wrapper makes the check more self-explainable and also
reusable for any further other uses.

Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
2009-11-10 11:23:43 +01:00
Frederic Weisbecker
24f1e32c60 hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events
This patch rebase the implementation of the breakpoints API on top of
perf events instances.

Each breakpoints are now perf events that handle the
register scheduling, thread/cpu attachment, etc..

The new layering is now made as follows:

       ptrace       kgdb      ftrace   perf syscall
          \          |          /         /
           \         |         /         /
                                        /
            Core breakpoint API        /
                                      /
                     |               /
                     |              /

              Breakpoints perf events

                     |
                     |

               Breakpoints PMU ---- Debug Register constraints handling
                                    (Part of core breakpoint API)
                     |
                     |

             Hardware debug registers

Reasons of this rewrite:

- Use the centralized/optimized pmu registers scheduling,
  implying an easier arch integration
- More powerful register handling: perf attributes (pinned/flexible
  events, exclusive/non-exclusive, tunable period, etc...)

Impact:

- New perf ABI: the hardware breakpoints counters
- Ptrace breakpoints setting remains tricky and still needs some per
  thread breakpoints references.

Todo (in the order):

- Support breakpoints perf counter events for perf tools (ie: implement
  perf_bpcounter_event())
- Support from perf tools

Changes in v2:

- Follow the perf "event " rename
- The ptrace regression have been fixed (ptrace breakpoint perf events
  weren't released when a task ended)
- Drop the struct hw_breakpoint and store generic fields in
  perf_event_attr.
- Separate core and arch specific headers, drop
  asm-generic/hw_breakpoint.h and create linux/hw_breakpoint.h
- Use new generic len/type for breakpoint
- Handle off case: when breakpoints api is not supported by an arch

Changes in v3:

- Fix broken CONFIG_KVM, we need to propagate the breakpoint api
  changes to kvm when we exit the guest and restore the bp registers
  to the host.

Changes in v4:

- Drop the hw_breakpoint_restore() stub as it is only used by KVM
- EXPORT_SYMBOL_GPL hw_breakpoint_restore() as KVM can be built as a
  module
- Restore the breakpoints unconditionally on kvm guest exit:
  TIF_DEBUG_THREAD doesn't anymore cover every cases of running
  breakpoints and vcpu->arch.switch_db_regs might not always be
  set when the guest used debug registers.
  (Waiting for a reliable optimization)

Changes in v5:

- Split-up the asm-generic/hw-breakpoint.h moving to
  linux/hw_breakpoint.h into a separate patch
- Optimize the breakpoints restoring while switching from kvm guest
  to host. We only want to restore the state if we have active
  breakpoints to the host, otherwise we don't care about messed-up
  address registers.
- Add asm/hw_breakpoint.h to Kbuild
- Fix bad breakpoint type in trace_selftest.c

Changes in v6:

- Fix wrong header inclusion in trace.h (triggered a build
  error with CONFIG_FTRACE_SELFTEST

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jan Kiszka <jan.kiszka@web.de>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
2009-11-08 15:34:42 +01:00
Gleb Natapov
abb3911965 KVM: get_tss_base_addr() should return a gpa_t
If TSS we are switching to resides in high memory task switch will fail
since address will be truncated. Windows2k3 does this sometimes when
running with more then 4G

Cc: stable@kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-11-04 12:42:36 -02:00
Jan Kiszka
a9e38c3e01 KVM: x86: Catch potential overrun in MCE setup
We only allocate memory for 32 MCE banks (KVM_MAX_MCE_BANKS) but we
allow user space to fill up to 255 on setup (mcg_cap & 0xff), corrupting
kernel memory. Catch these overflows.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-11-04 12:42:35 -02:00
Frederic Weisbecker
0f8f86c7bd Merge commit 'perf/core' into perf/hw-breakpoint
Conflicts:
	kernel/Makefile
	kernel/trace/Makefile
	kernel/trace/trace.h
	samples/Makefile

Merge reason: We need to be uptodate with the perf events development
branch because we plan to rewrite the breakpoints API on top of
perf events.
2009-10-18 01:12:33 +02:00
Frederik Deweerdt
8a8365c560 KVM: MMU: fix pointer cast
On a 32 bits compile, commit 3da0dd433d
introduced the following warnings:

arch/x86/kvm/mmu.c: In function ‘kvm_set_pte_rmapp’:
arch/x86/kvm/mmu.c:770: warning: cast to pointer from integer of different size
arch/x86/kvm/mmu.c: In function ‘kvm_set_spte_hva’:
arch/x86/kvm/mmu.c:849: warning: cast from pointer to integer of different size

The following patch uses 'unsigned long' instead of u64 to match the
pointer size on both arches.

Signed-off-by: Frederik Deweerdt <frederik.deweerdt@xprog.eu>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-16 12:30:26 -03:00
Marcelo Tosatti
ace1546487 KVM: use proper hrtimer function to retrieve expiration time
hrtimer->base can be temporarily NULL due to racing hrtimer_start.
See switch_hrtimer_base/lock_hrtimer_base.

Use hrtimer_get_remaining which is robust against it.

CC: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-10-16 12:30:25 -03:00
Izik Eidus
3da0dd433d KVM: add support for change_pte mmu notifiers
this is needed for kvm if it want ksm to directly map pages into its
shadow page tables.

[marcelo: cast pfn assignment to u64]

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 17:04:53 +02:00
Izik Eidus
1403283acc KVM: MMU: add SPTE_HOST_WRITEABLE flag to the shadow ptes
this flag notify that the host physical page we are pointing to from
the spte is write protected, and therefore we cant change its access
to be write unless we run get_user_pages(write = 1).

(this is needed for change_pte support in kvm)

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 17:04:50 +02:00
Izik Eidus
acb66dd051 KVM: MMU: dont hold pagecount reference for mapped sptes pages
When using mmu notifiers, we are allowed to remove the page count
reference tooken by get_user_pages to a specific page that is mapped
inside the shadow page tables.

This is needed so we can balance the pagecount against mapcount
checking.

(Right now kvm increase the pagecount and does not increase the
mapcount when mapping page into shadow page table entry,
so when comparing pagecount against mapcount, you have no
reliable result.)

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 17:04:48 +02:00
Avi Kivity
6a54435560 KVM: Prevent overflow in KVM_GET_SUPPORTED_CPUID
The number of entries is multiplied by the entry size, which can
overflow on 32-bit hosts.  Bound the entry count instead.

Reported-by: David Wagner <daw@cs.berkeley.edu>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-10-04 17:04:16 +02:00
Marcelo Tosatti
eb5109e311 KVM: VMX: flush TLB with INVEPT on cpu migration
It is possible that stale EPTP-tagged mappings are used, if a
vcpu migrates to a different pcpu.

Set KVM_REQ_TLB_FLUSH in vmx_vcpu_load, when switching pcpus, which
will invalidate both VPID and EPT mappings on the next vm-entry.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 13:57:24 +02:00
Aurelien Jarno
b2d83cfa3f KVM: fix LAPIC timer period overflow
Don't overflow when computing the 64-bit period from 32-bit registers.

Fixes sourceforge bug #2826486.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 13:57:23 +02:00
Joerg Roedel
20824f30bb KVM: SVM: Handle tsc in svm_get_msr/svm_set_msr correctly
When running nested we need to touch the l1 guests
tsc_offset. Otherwise changes will be lost or a wrong value
be read.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 13:57:23 +02:00
Joerg Roedel
77b1ab1732 KVM: SVM: Fix tsc offset adjustment when running nested
When svm_vcpu_load is called while the vcpu is running in
guest mode the tsc adjustment made there is lost on the next
emulated #vmexit. This causes the tsc running backwards in
the guest. This patch fixes the issue by also adjusting the
tsc_offset in the emulated hsave area so that it will not
get lost.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04 13:57:22 +02:00
Ingo Molnar
dca2d6ac09 Merge branch 'linus' into tracing/hw-breakpoints
Conflicts:
	arch/x86/kernel/process_64.c

Semantic conflict fixed in:
	arch/x86/kvm/x86.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 12:18:15 +02:00
Linus Torvalds
69def9f05d Merge branch 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (202 commits)
  MAINTAINERS: update KVM entry
  KVM: correct error-handling code
  KVM: fix compile warnings on s390
  KVM: VMX: Check cpl before emulating debug register access
  KVM: fix misreporting of coalesced interrupts by kvm tracer
  KVM: x86: drop duplicate kvm_flush_remote_tlb calls
  KVM: VMX: call vmx_load_host_state() only if msr is cached
  KVM: VMX: Conditionally reload debug register 6
  KVM: Use thread debug register storage instead of kvm specific data
  KVM guest: do not batch pte updates from interrupt context
  KVM: Fix coalesced interrupt reporting in IOAPIC
  KVM guest: fix bogus wallclock physical address calculation
  KVM: VMX: Fix cr8 exiting control clobbering by EPT
  KVM: Optimize kvm_mmu_unprotect_page_virt() for tdp
  KVM: Document KVM_CAP_IRQCHIP
  KVM: Protect update_cr8_intercept() when running without an apic
  KVM: VMX: Fix EPT with WP bit change during paging
  KVM: Use kvm_{read,write}_guest_virt() to read and write segment descriptors
  KVM: x86 emulator: Add adc and sbb missing decoder flags
  KVM: Add missing #include
  ...
2009-09-14 17:43:43 -07:00
Avi Kivity
0a79b00952 KVM: VMX: Check cpl before emulating debug register access
Debug registers may only be accessed from cpl 0.  Unfortunately, vmx will
code to emulate the instruction even though it was issued from guest
userspace, possibly leading to an unexpected trap later.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 18:11:10 +03:00
Gleb Natapov
4da748960a KVM: fix misreporting of coalesced interrupts by kvm tracer
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 18:11:09 +03:00
Marcelo Tosatti
e3904e6ed0 KVM: x86: drop duplicate kvm_flush_remote_tlb calls
kvm_mmu_slot_remove_write_access already calls it.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 18:11:08 +03:00
Gleb Natapov
542423b0dd KVM: VMX: call vmx_load_host_state() only if msr is cached
No need to call it before each kvm_(set|get)_msr_common()

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 18:11:07 +03:00
Avi Kivity
e8a48342e9 KVM: VMX: Conditionally reload debug register 6
Only reload debug register 6 if we're running with the guest's
debug registers.  Saves around 150 cycles from the guest lightweight
exit path.

dr6 contains a couple of bits that are updated on #DB, so intercept
that unconditionally and update those bits then.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 18:11:06 +03:00
Avi Kivity
3d53c27d05 KVM: Use thread debug register storage instead of kvm specific data
Instead of saving the debug registers from the processor to a kvm data
structure, rely in the debug registers stored in the thread structure.
This allows us not to save dr6 and dr7.

Reduces lightweight vmexit cost by 350 cycles, or 11 percent.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 18:11:04 +03:00
Gleb Natapov
5fff7d270b KVM: VMX: Fix cr8 exiting control clobbering by EPT
Don't call adjust_vmx_controls() two times for the same control.
It restores options that were dropped earlier.  This loses us the cr8
exit control, which causes a massive performance regression Windows x64.

Cc: stable@kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:57 +03:00
Avi Kivity
60f24784a9 KVM: Optimize kvm_mmu_unprotect_page_virt() for tdp
We know no pages are protected, so we can short-circuit the whole thing
(including fairly nasty guest memory accesses).

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:56 +03:00
Avi Kivity
88c808fd42 KVM: Protect update_cr8_intercept() when running without an apic
update_cr8_intercept() can be triggered from userspace while there
is no apic present.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:54 +03:00
Sheng Yang
95eb84a758 KVM: VMX: Fix EPT with WP bit change during paging
QNX update WP bit when paging enabled, which is not covered yet. This one fix
QNX boot with EPT.

Cc: stable@kernel.org
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:53 +03:00
Mikhail Ershov
d9048d3278 KVM: Use kvm_{read,write}_guest_virt() to read and write segment descriptors
Segment descriptors tables can be placed on two non-contiguous pages.
This patch makes reading segment descriptors by linear address.

Signed-off-by: Mikhail Ershov <Mike.Ershov@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:52 +03:00
Mohammed Gamal
7bdb588827 KVM: x86 emulator: Add adc and sbb missing decoder flags
Add missing decoder flags for adc and sbb instructions
(opcodes 0x14-0x15, 0x1c-0x1d)

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:51 +03:00
Avi Kivity
56e8231841 KVM: Rename x86_emulate.c to emulate.c
We're in arch/x86, what could we possibly be emulating?

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:45 +03:00
Anthony Liguori
c0c7c04b87 KVM: When switching to a vm8086 task, load segments as 16-bit
According to 16.2.5 in the SDM, eflags.vm in the tss is consulted before loading
and new segments.  If eflags.vm == 1, then the segments are treated as 16-bit
segments.  The LDTR and TR are not normally available in vm86 mode so if they
happen to somehow get loaded, they need to be treated as 32-bit segments.

This fixes an invalid vmentry failure in a custom OS that was happening after
a task switch into vm8086 mode.  Since the segments were being mistakenly
treated as 32-bit, we loaded garbage state.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:44 +03:00
Avi Kivity
345dcaa8fd KVM: VMX: Adjust rflags if in real mode emulation
We set rflags.vm86 when virtualizing real mode to do through vm8086 mode;
so we need to take it out again when reading rflags.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:43 +03:00
Avi Kivity
52c7847d12 KVM: SVM: Drop tlb flush workaround in npt
It is no longer possible to reproduce the problem any more, so presumably
it has been fixed.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:40 +03:00
Gleb Natapov
cb142eb743 KVM: Update cr8 intercept when APIC TPR is changed by userspace
Since on vcpu entry we do it only if apic is enabled we should do
it when TPR is changed while apic is disabled. This happens when windows
resets HW without setting TPR to zero.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:39 +03:00
Joerg Roedel
4b6e4dca70 KVM: SVM: enable nested svm by default
Nested SVM is (in my experience) stable enough to be enabled by
default. So omit the requirement to pass a module parameter.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:38 +03:00
Joerg Roedel
108768de55 KVM: SVM: check for nested VINTR flag in svm_interrupt_allowed
Not checking for this flag breaks any nested hypervisor that does not
set VINTR. So fix it with this patch.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:37 +03:00
Joerg Roedel
26666957a5 KVM: SVM: move nested_svm_intr main logic out of if-clause
This patch removes one indentation level from nested_svm_intr and
makes the logic more readable.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:36 +03:00
Joerg Roedel
cda0ffdd86 KVM: SVM: remove unnecessary is_nested check from svm_cpu_run
This check is not necessary. We have to sync the vcpu->arch.cr2 always
back to the VMCB. This patch remove the is_nested check.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:34 +03:00
Joerg Roedel
410e4d573d KVM: SVM: move special nested exit handling to separate function
This patch moves the handling for special nested vmexits like #pf to a
separate function. This makes the kvm_override parameter obsolete and
makes the code more readable.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:33 +03:00
Joerg Roedel
1f8da47805 KVM: SVM: handle errors in vmrun emulation path appropriatly
If nested svm fails to load the msrpm the vmrun succeeds with the old
msrpm which is not correct. This patch changes the logic to roll back
to host mode in case the msrpm cannot be loaded.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:32 +03:00
Joerg Roedel
ea8e064fe2 KVM: SVM: remove nested_svm_do and helper functions
This function is not longer required. So remove it.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:31 +03:00
Joerg Roedel
9738b2c97d KVM: SVM: clean up nested vmrun path
This patch removes the usage of nested_svm_do from the vmrun emulation
path.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:29 +03:00
Joerg Roedel
9966bf6872 KVM: SVM: clean up nestec vmload/vmsave paths
This patch removes the usage of nested_svm_do from the vmload and
vmsave emulation code paths.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:46:28 +03:00
Joerg Roedel
3d62d9aa98 KVM: SVM: clean up nested_svm_exit_handled_msr
This patch changes nested svm to call nested_svm_exit_handled_msr
directly and not through nested_svm_do.

[alex: fix oops due to nested kmap_atomics]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 10:45:43 +03:00
Joerg Roedel
34f80cfad5 KVM: SVM: get rid of nested_svm_vmexit_real
This patch is the starting point of removing nested_svm_do from the
nested svm code. The nested_svm_do function basically maps two guest
physical pages to host virtual addresses and calls a passed function
on it. This function pointer code flow is hard to read and not the
best technical solution here.
As a side effect this patch indroduces the nested_svm_[un]map helper
functions.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:26 +03:00
Joerg Roedel
0295ad7de8 KVM: SVM: simplify nested_svm_check_exception
Makes the code of this function more readable by removing on
indentation level for the core logic.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:25 +03:00
Joerg Roedel
9c4e40b994 KVM: SVM: do nested vmexit in nested_svm_exit_handled
If this function returns true a nested vmexit is required. Move that
vmexit into the nested_svm_exit_handled function. This also simplifies
the handling of nested #pf intercepts in this function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:25 +03:00
Joerg Roedel
4c2161aed5 KVM: SVM: consolidate nested_svm_exit_handled
When caching guest intercepts there is no need anymore for the
nested_svm_exit_handled_real function. So move its code into
nested_svm_exit_handled.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:24 +03:00
Joerg Roedel
aad42c641c KVM: SVM: cache nested intercepts
When the nested intercepts are cached we don't need to call
get_user_pages and/or map the nested vmcb on every nested #vmexit to
check who will handle the intercept.
Further this patch aligns the emulated svm behavior better to real
hardware.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:24 +03:00
Joerg Roedel
e6aa9abd73 KVM: SVM: move nested svm state into seperate struct
This makes it more clear for which purpose these members in the vcpu_svm
exist.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:24 +03:00
Joerg Roedel
a5c3832dfe KVM: SVM: complete interrupts after handling nested exits
The interrupt completion code must run after nested exits are handled
because not injected interrupts or exceptions may be handled by the l1
guest first.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:24 +03:00
Joerg Roedel
0460a979b4 KVM: SVM: copy only necessary parts of the control area on vmrun/vmexit
The vmcb control area contains more then 800 bytes of reserved fields
which are unnecessarily copied. Fix this by introducing a copy
function which only copies the relevant part and saves time.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:23 +03:00
Joerg Roedel
defbba5660 KVM: SVM: optimize nested vmrun
Only copy the necessary parts of the vmcb save area on vmrun and save
precious time.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:23 +03:00
Joerg Roedel
33740e4009 KVM: SVM: optimize nested #vmexit
It is more efficient to copy only the relevant parts of the vmcb back to
the nested vmcb when we emulate an vmexit.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:23 +03:00
Joerg Roedel
2af9194d1b KVM: SVM: add helper functions for global interrupt flag
This patch makes the code easier to read when it comes to setting,
clearing and checking the status of the virtualized global
interrupt flag for the VCPU.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:23 +03:00
Gleb Natapov
88ba63c265 KVM: Replace pic_lock()/pic_unlock() with direct call to spinlock functions
They are not doing anything else now.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:22 +03:00
Gleb Natapov
938396a234 KVM: Call ack notifiers from PIC when guest OS acks an IRQ.
Currently they are called when irq vector is been delivered.  Calling ack
notifiers at this point is wrong.  Device assignment ack notifier enables
host interrupts, but guest not yet had a chance to clear interrupt
condition in a device.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:22 +03:00
Gleb Natapov
956f97cf66 KVM: Call kvm_vcpu_kick() inside pic spinlock
d5ecfdd25 moved it out because back than it was impossible to
call it inside spinlock. This restriction no longer exists.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:21 +03:00
Roel Kluin
3a34a8810b KVM: fix EFER read buffer overflow
Check whether index is within bounds before grabbing the element.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:21 +03:00
Amit Shah
1f3ee616dd KVM: ignore reads to perfctr msrs
We ignore writes to the perfctr msrs. Ignore reads as well.

Kaspersky antivirus crashes Windows guests if it can't read
these MSRs.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:21 +03:00
Avi Kivity
eab4b8aa34 KVM: VMX: Optimize vmx_get_cpl()
Instead of calling vmx_get_segment() (which reads a whole bunch of
vmcs fields), read only the cs selector which contains the cpl.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:21 +03:00
Jan Kiszka
07708c4af1 KVM: x86: Disallow hypercalls for guest callers in rings > 0
So far unprivileged guest callers running in ring 3 can issue, e.g., MMU
hypercalls. Normally, such callers cannot provide any hand-crafted MMU
command structure as it has to be passed by its physical address, but
they can still crash the guest kernel by passing random addresses.

To close the hole, this patch considers hypercalls valid only if issued
from guest ring 0. This may still be relaxed on a per-hypercall base in
the future once required.

Cc: stable@kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:20 +03:00
Marcelo Tosatti
b90c062c65 KVM: MMU: fix bogus alloc_mmu_pages assignment
Remove the bogus n_free_mmu_pages assignment from alloc_mmu_pages.

It breaks accounting of mmu pages, since n_free_mmu_pages is modified
but the real number of pages remains the same.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:20 +03:00
Izik Eidus
3b80fffe2b KVM: MMU: make __kvm_mmu_free_some_pages handle empty list
First check if the list is empty before attempting to look at list
entries.

Cc: stable@kernel.org
Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:20 +03:00
Bartlomiej Zolnierkiewicz
95fb4eb698 KVM: remove superfluous NULL pointer check in kvm_inject_pit_timer_irqs()
This takes care of the following entries from Dan's list:

arch/x86/kvm/i8254.c +714 kvm_inject_pit_timer_irqs(6) warning: variable derefenced in initializer 'vcpu'
arch/x86/kvm/i8254.c +714 kvm_inject_pit_timer_irqs(6) warning: variable derefenced before check 'vcpu'

Reported-by: Dan Carpenter <error27@gmail.com>
Cc: corbet@lwn.net
Cc: eteo@redhat.com
Cc: Julia Lawall <julia@diku.dk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:19 +03:00
Joerg Roedel
344f414fa0 KVM: report 1GB page support to userspace
If userspace knows that the kernel part supports 1GB pages it can enable
the corresponding cpuid bit so that guests actually use GB pages.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:19 +03:00
Joerg Roedel
7e4e4056f7 KVM: MMU: shadow support for 1gb pages
This patch adds support for shadow paging to the 1gb page table code in KVM.
With this code the guest can use 1gb pages even if the host does not support
them.

[ Marcelo: fix shadow page collision on pmd level if a guest 1gb page is mapped
           with 4kb ptes on host level ]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:19 +03:00
Joerg Roedel
e04da980c3 KVM: MMU: make page walker aware of mapping levels
The page walker may be used with nested paging too when accessing mmio
areas.  Make it support the additional page-level too.

[ Marcelo: fix reserved bit check for 1gb pte ]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:18 +03:00
Joerg Roedel
852e3c19ac KVM: MMU: make direct mapping paths aware of mapping levels
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:18 +03:00
Joerg Roedel
d25797b24c KVM: MMU: rename is_largepage_backed to mapping_level
With the new name and the corresponding backend changes this function
can now support multiple hugepage sizes.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:18 +03:00
Joerg Roedel
44ad9944f1 KVM: MMU: make rmap code aware of mapping levels
This patch removes the largepage parameter from the rmap_add function.
Together with rmap_remove this function now uses the role.level field to
find determine if the page is a huge page.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:18 +03:00
Marcelo Tosatti
1444885a04 KVM: limit lapic periodic timer frequency
Otherwise its possible to starve the host by programming lapic timer
with a very high frequency.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:17 +03:00
Mikhail Ershov
5f0269f5d7 KVM: Align cr8 threshold when userspace changes cr8
Commit f0a3602c20 ("KVM: Move interrupt injection logic to x86.c") does not
update the cr8 intercept if the lapic is disabled, so when userspace updates
cr8, the cr8 threshold control is not updated and we are left with illegal
control fields.

Fix by explicitly resetting the cr8 threshold.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:17 +03:00
Jan Kiszka
7f582ab6d8 KVM: VMX: Avoid to return ENOTSUPP to userland
Choose some allowed error values for the cases VMX returned ENOTSUPP so
far as these values could be returned by the KVM_RUN IOCTL.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:17 +03:00
Gleb Natapov
84fde248fe KVM: PIT: Unregister ack notifier callback when freeing
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:16 +03:00
Sheng Yang
b927a3cec0 KVM: VMX: Introduce KVM_SET_IDENTITY_MAP_ADDR ioctl
Now KVM allow guest to modify guest's physical address of EPT's identity mapping page.

(change from v1, discard unnecessary check, change ioctl to accept parameter
address rather than value)

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:16 +03:00
Akinobu Mita
b792c344df KVM: x86: use kvm_get_gdt() and kvm_read_ldt()
Use kvm_get_gdt() and kvm_read_ldt() to reduce inline assembly code.

Cc: Avi Kivity <avi@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:15 +03:00
Akinobu Mita
46a359e715 KVM: x86: use get_desc_base() and get_desc_limit()
Use get_desc_base() and get_desc_limit() to get the base address and
limit in desc_struct.

Cc: Avi Kivity <avi@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:15 +03:00
Marcelo Tosatti
6a1ac77110 KVM: MMU: fix missing locking in alloc_mmu_pages
n_requested_mmu_pages/n_free_mmu_pages are used by
kvm_mmu_change_mmu_pages to calculate the number of pages to zap.

alloc_mmu_pages, called from the vcpu initialization path, modifies this
variables without proper locking, which can result in a negative value
in kvm_mmu_change_mmu_pages (say, with cpu hotplug).

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:14 +03:00
Sheng Yang
3662cb1cd6 KVM: Discard unnecessary kvm_mmu_flush_tlb() in kvm_mmu_load()
set_cr3() should already cover the TLB flushing.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:14 +03:00
Gleb Natapov
4088bb3cae KVM: silence lapic kernel messages that can be triggered by a guest
Some Linux versions (f8) try to read EOI register that is write only.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10 08:33:14 +03:00
Gleb Natapov
a1b37100d9 KVM: Reduce runnability interface with arch support code
Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from
interface between general code and arch code. kvm_arch_vcpu_runnable()
checks for interrupts instead.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:13 +03:00
Gleb Natapov
b59bb7bdf0 KVM: Move exception handling to the same place as other events
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:13 +03:00