Commit graph

1088 commits

Author SHA1 Message Date
Gui Jianfeng 3129994458 KVM: VMX: change to use bool return values
Make use of bool as return values, and remove some useless
bool value converting. Thanks Avi to point this out.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:51 +03:00
Gleb Natapov 49c6799a2c KVM: Remove pointer to rflags from realmode_set_cr parameters.
Mov reg, cr instruction doesn't change flags in any meaningful way, so
no need to update rflags after instruction execution.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:50 +03:00
Gleb Natapov af5b4f7ff7 KVM: x86 emulator: check return value against correct define
Check return value against correct define instead of open code
the value.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:48 +03:00
Gleb Natapov c73e197bc5 KVM: x86 emulator: fix RCX access during rep emulation
During rep emulation access length to RCX depends on current address
mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:47 +03:00
Gleb Natapov d6d367d678 KVM: x86 emulator: Fix DstAcc decoding.
Set correct operation length. Add RAX (64bit) handling.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:45 +03:00
Avi Kivity 08e850c653 KVM: MMU: Reinstate pte prefetch on invlpg
Commit fb341f57 removed the pte prefetch on guest invlpg, citing guest races.
However, the SDM is adamant that prefetch is allowed:

  "The processor may create entries in paging-structure caches for
   translations required for prefetches and for accesses that are a
   result of speculative execution that would never actually occur
   in the executed code path."

And, in fact, there was a race in the prefetch code: we picked up the pte
without the mmu lock held, so an older invlpg could install the pte over
a newer invlpg.

Reinstate the prefetch logic, but this time note whether another invlpg has
executed using a counter.  If a race occured, do not install the pte.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:43 +03:00
Avi Kivity fbc5d139bb KVM: MMU: Do not instantiate nontrapping spte on unsync page
The update_pte() path currently uses a nontrapping spte when a nonpresent
(or nonaccessed) gpte is written.  This is fine since at present it is only
used on sync pages.  However, on an unsync page this will cause an endless
fault loop as the guest is under no obligation to invlpg a gpte that
transitions from nonpresent to present.

Needed for the next patch which reinstates update_pte() on invlpg.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:42 +03:00
Avi Kivity 4a5f48f666 KVM: Don't follow an atomic operation by a non-atomic one
Currently emulated atomic operations are immediately followed by a non-atomic
operation, so that kvm_mmu_pte_write() can be invoked.  This updates the mmu
but undoes the whole point of doing things atomically.

Fix by only performing the atomic operation and the mmu update, and avoiding
the non-atomic write.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:40 +03:00
Avi Kivity daea3e73cb KVM: Make locked operations truly atomic
Once upon a time, locked operations were emulated while holding the mmu mutex.
Since mmu pages were write protected, it was safe to emulate the writes in
a non-atomic manner, since there could be no other writer, either in the
guest or in the kernel.

These days emulation takes place without holding the mmu spinlock, so the
write could be preempted by an unshadowing event, which exposes the page
to writes by the guest.  This may cause corruption of guest page tables.

Fix by using an atomic cmpxchg for these operations.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:39 +03:00
Avi Kivity 72016f3a42 KVM: MMU: Consolidate two guest pte reads in kvm_mmu_pte_write()
kvm_mmu_pte_write() reads guest ptes in two different occasions, both to
allow a 32-bit pae guest to update a pte with 4-byte writes.  Consolidate
these into a single read, which also allows us to consolidate another read
from an invlpg speculating a gpte into the shadow page table.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:37 +03:00
Wei Yongjun 160d2f6c0c KVM: x86: fix the error of ioctl KVM_IRQ_LINE if no irq chip
If no irq chip in kernel, ioctl KVM_IRQ_LINE will return -EFAULT.
But I see in other place such as KVM_[GET|SET]IRQCHIP, -ENXIO is
return. So this patch used -ENXIO instead of -EFAULT.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:31 +03:00
Wei Yongjun ec68798c8f KVM: x86: Use native_store_idt() instead of kvm_get_idt()
This patch use generic linux function native_store_idt()
instead of kvm_get_idt(), and also removed the useless
function kvm_get_idt().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:28 +03:00
Avi Kivity 5c1c85d08d KVM: Trace exception injection
Often an exception can help point out where things start to go wrong.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:15:27 +03:00
Avi Kivity 5bfd8b5455 KVM: Move kvm_exit tracepoint rip reading inside tracepoint
Reading rip is expensive on vmx, so move it inside the tracepoint so we only
incur the cost if tracing is enabled.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:15:25 +03:00
Minchan Kim d4f64b6cad KVM: remove redundant initialization of page->private
The prep_new_page() in page allocator calls set_page_private(page, 0).
So we don't need to reinitialize private of page.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Avi Kivity<avi@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:15:24 +03:00
Xiao Guangrong 2ed152afc7 KVM: cleanup kvm trace
This patch does:

 - no need call tracepoint_synchronize_unregister() when kvm module
   is unloaded since ftrace can handle it

 - cleanup ftrace's macro

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:15:22 +03:00
Gleb Natapov 835e6b8047 KVM: x86 emulator mark VMMCALL and LMSW as privileged
LMSW is present in both group tables. It was marked privileged only in
one of them. Intel analog of VMMCALL is already marked privileged.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:18 +03:00
Joerg Roedel f71385383f KVM: SVM: Ignore lower 12 bit of nested msrpm_pa
These bits are ignored by the hardware too. Implement this
for nested svm too.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:16 +03:00
Joerg Roedel ce2ac085ff KVM; SVM: Add correct handling of nested iopm
This patch adds the correct handling of the nested io
permission bitmap. Old behavior was to not lookup the port
in the iopm but only reinject an io intercept to the guest.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:15 +03:00
Joerg Roedel 0d6b35378e KVM: SVM: Use svm_msrpm_offset in nested_svm_exit_handled_msr
There is a generic function now to calculate msrpm offsets.
Use that function in nested_svm_exit_handled_msr() remove
the duplicate logic (which had a bug anyway).

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:13 +03:00
Joerg Roedel 323c3d809b KVM: SVM: Optimize nested svm msrpm merging
This patch optimizes the way the msrpm of the host and the
guest are merged. The old code merged the 2 msrpm pages
completly. This code needed to touch 24kb of memory for that
operation. The optimized variant this patch introduces
merges only the parts where the host msrpm may contain zero
bits. This reduces the amount of memory which is touched to
48 bytes.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:12 +03:00
Joerg Roedel ac72a9b733 KVM: SVM: Introduce direct access msr list
This patch introduces a list with all msrs a guest might
have direct access to and changes the svm_vcpu_init_msrpm
function to use this list.
It also adds a check to set_msr_interception which triggers
a warning if a developer changes a msr intercept that is not
in the list.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:10 +03:00
Joerg Roedel 455716fa94 KVM: SVM: Move msrpm offset calculation to seperate function
The algorithm to find the offset in the msrpm for a given
msr is needed at other places too. Move that logic to its
own function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:08 +03:00
Joerg Roedel d24778265a KVM: SVM: Return correct values in nested_svm_exit_handled_msr
The nested_svm_exit_handled_msr() returned an bool which is
a bug. I worked by accident because the exected integer
return values match with the true and false values. This
patch changes the return value to int and let the function
return the correct values.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:07 +03:00
Andrea Gelmini 0fc5c3a54d KVM: arch/x86/kvm/kvm_timer.h checkpatch cleanup
arch/x86/kvm/kvm_timer.h:13: ERROR: code indent should use tabs where possible

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:14:42 +03:00
Gleb Natapov ea79849d4c KVM: x86 emulator: Implement jmp far opcode ff/5
Implement jmp far opcode ff/5. It is used by multiboot loader.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:45 +03:00
Gleb Natapov e35b7b9c9e KVM: x86 emulator: Add decoding of 16bit second in memory argument
Add decoding of Ep type of argument used by callf/jmpf.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:42 +03:00
Gleb Natapov 2d49ec72d3 KVM: move segment_base() into vmx.c
segment_base() is used only by vmx so move it there.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:39 +03:00
Gleb Natapov 254d4d48a5 KVM: fix segment_base() error checking
fix segment_base() to properly check for null segment selector and
avoid accessing NULL pointer if ldt selector in null.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:35 +03:00
Gleb Natapov d6ab1ed446 KVM: Drop kvm_get_gdt() in favor of generic linux function
Linux now has native_store_gdt() to do the same. Use it instead of
kvm local version.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:32 +03:00
Joerg Roedel 197717d581 KVM: SVM: Clear exit_info for injected INTR exits
When injecting an vmexit.intr into the nested hypervisor
there might be leftover values in the exit_info fields.
Clear them to not confuse nested hypervisors.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:26 +03:00
Joerg Roedel 7f5d8b5600 KVM: SVM: Handle nested selective_cr0 intercept correctly
If we have the following situation with nested svm:

1. Host KVM intercepts cr0 writes
2. Guest hypervisor intercepts only selective cr0 writes

Then we get an cr0 write intercept which is handled on the
host. But that intercepts may actually be a selective cr0
intercept for the guest. This patch checks for this
condition and injects a selective cr0 intercept if needed.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:23 +03:00
Joerg Roedel b44ea385d8 KVM: x86: Don't set arch.cr0 in kvm_set_cr0
The vcpu->arch.cr0 variable is already set in the
architecture specific set_cr0 callbacks. There is no need to
set it in the common code.
This allows the architecture code to keep the old arch.cr0
value if it wants. This is required for nested svm to decide
if a selective_cr0 exit needs to be injected.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:20 +03:00
Joerg Roedel 82494028df KVM: SVM: Ignore write of hwcr.ignne
Hyper-V as a guest wants to write this bit. This patch
ignores it.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:17 +03:00
Joerg Roedel 4a810181c8 KVM: SVM: Implement emulation of vm_cr msr
This patch implements the emulation of the vm_cr msr for
nested svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:14 +03:00
Joerg Roedel 2e554e8d67 KVM: SVM: Add kvm_nested_intercepts tracepoint
This patch adds a tracepoint to get information about the
most important intercept bitmasks from the nested vmcb.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:10 +03:00
Joerg Roedel ecf1405df2 KVM: SVM: Restore tracing of nested vmcb address
A recent change broke tracing of the nested vmcb address. It
was reported as 0 all the time. This patch fixes it.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:07 +03:00
Joerg Roedel 887f500ca1 KVM: SVM: Check for nested intercepts on NMI injection
This patch implements the NMI intercept checking for nested
svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:04 +03:00
Joerg Roedel 0e5cbe368b KVM: SVM: Reset MMU on nested_svm_vmrun for NPT too
Without resetting the MMU the gva_to_pga function will not
work reliably when the vcpu is running in nested context.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:53:01 +03:00
Joerg Roedel e02317153e KVM: SVM: Coding style cleanup
This patch removes whitespace errors, fixes comment formats
and most of checkpatch warnings. Now vim does not show
c-space-errors anymore.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:52:58 +03:00
Jan Kiszka 83bf0002c9 KVM: x86: Preserve injected TF across emulation
Call directly into the vendor services for getting/setting rflags in
emulate_instruction to ensure injected TF survives the emulation.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:52:55 +03:00
Jan Kiszka c310bac5a2 KVM: x86: Drop RF manipulation for guest single-stepping
RF is not required for injecting TF as the latter will trigger only
after an instruction execution anyway. So do not touch RF when arming or
disarming guest single-step mode.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:52:51 +03:00
Jan Kiszka 66b7138f91 KVM: SVM: Emulate nRIP feature when reinjecting INT3
When in guest debugging mode, we have to reinject those #BP software
exceptions that are caused by guest-injected INT3. As older AMD
processors do not support the required nRIP VMCB field, try to emulate
it by moving RIP past the instruction on exception injection. Fix it up
again in case the injection failed and we were able to catch this. This
does not work for unintercepted faults, but it is better than doing
nothing.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:00:43 +03:00
Jan Kiszka f92653eeb4 KVM: x86: Add kvm_is_linear_rip
Based on Gleb's suggestion: Add a helper kvm_is_linear_rip that matches
a given linear RIP against the current one. Use this for guest
single-stepping, more users will follow.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:00:40 +03:00
Jan Kiszka 116a4752c8 KVM: SVM: Move svm_queue_exception
Move svm_queue_exception past skip_emulated_instruction to allow calling
it later on.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 13:00:37 +03:00
Jan Kiszka 50a085bdd4 KVM: x86: Kick VCPU outside PIC lock again
This restores the deferred VCPU kicking before 956f97cf. We need this
over -rt as wake_up* requires non-atomic context in this configuration.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:39:28 +03:00
Jan Kiszka a1efbe77c1 KVM: x86: Add support for saving&restoring debug registers
So far user space was not able to save and restore debug registers for
migration or after reset. Plug this hole.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:39:10 +03:00
Jan Kiszka 48005f64d0 KVM: x86: Save&restore interrupt shadow mask
The interrupt shadow created by STI or MOV-SS-like operations is part of
the VCPU state and must be preserved across migration. Transfer it in
the spare padding field of kvm_vcpu_events.interrupt.

As a side effect we now have to make vmx_set_interrupt_shadow robust
against both shadow types being set. Give MOV SS a higher priority and
skip STI in that case to avoid that VMX throws a fault on next entry.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:38:28 +03:00
Jan Kiszka 03b82a30ea KVM: x86: Do not return soft events in vcpu_events
To avoid that user space migrates a pending software exception or
interrupt, mask them out on KVM_GET_VCPU_EVENTS. Without this, user
space would try to reinject them, and we would have to reconstruct the
proper instruction length for VMX event injection. Now the pending event
will be reinjected via executing the triggering instruction again.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:38:14 +03:00
Joerg Roedel 8fe546547c KVM: SVM: Fix wrong interrupt injection in enable_irq_windows
The nested_svm_intr() function does not execute the vmexit
anymore. Therefore we may still be in the nested state after
that function ran. This patch changes the nested_svm_intr()
function to return wether the irq window could be enabled.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:38:11 +03:00
Gleb Natapov 112592da0d KVM: drop unneeded kvm_run check in emulate_instruction()
vcpu->run is initialized on vcpu creation and can never be NULL
here.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:38:08 +03:00
Joerg Roedel 052ce6211c KVM: SVM: Remove newlines from nested trace points
The tracing infrastructure adds its own newlines. Remove
them from the trace point printk format strings.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:31 +03:00
Joerg Roedel 66a562f7e2 KVM: SVM: Make lazy FPU switching work with nested svm
The new lazy fpu switching code may disable cr0 intercepts
when running nested. This is a bug because the nested
hypervisor may still want to intercept cr0 which will break
in this situation. This patch fixes this issue and makes
lazy fpu switching working with nested svm.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:28 +03:00
Joerg Roedel 06fc777269 KVM: SVM: Activate nested state only when guest state is complete
Certain functions called during the emulated world switch
behave differently when the vcpu is running nested. This is
not the expected behavior during a world switch emulation.
This patch ensures that the nested state is activated only
if the vcpu is completly in nested state.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:25 +03:00
Joerg Roedel 88ab24adc7 KVM: SVM: Don't sync nested cr8 to lapic and back
This patch makes syncing of the guest tpr to the lapic
conditional on !nested. Otherwise a nested guest using the
TPR could freeze the guest.
Another important change this patch introduces is that the
cr8 intercept bits are no longer ORed at vmrun emulation if
the guest sets VINTR_MASKING in its VMCB. The reason is that
nested cr8 accesses need alway be handled by the nested
hypervisor because they change the shadow version of the
tpr.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:22 +03:00
Joerg Roedel 4c7da8cb43 KVM: SVM: Fix nested msr intercept handling
The nested_svm_exit_handled_msr() function maps only one
page of the guests msr permission bitmap. This patch changes
the code to use kvm_read_guest to fix the bug.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:19 +03:00
Joerg Roedel 6c3bd3d766 KVM: SVM: Annotate nested_svm_map with might_sleep()
The nested_svm_map() function can sleep and must not be
called from atomic context. So annotate that function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:16 +03:00
Joerg Roedel cdbbdc1210 KVM: SVM: Sync all control registers on nested vmexit
Currently the vmexit emulation does not sync control
registers were the access is typically intercepted by the
nested hypervisor. But we can not count on that intercepts
to sync these registers too and make the code
architecturally more correct.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:13 +03:00
Joerg Roedel b8e88bc8ff KVM: SVM: Fix schedule-while-atomic on nested exception handling
Move the actual vmexit routine out of code that runs with
irqs and preemption disabled.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:10 +03:00
Joerg Roedel 7597f129d8 KVM: SVM: Don't use kmap_atomic in nested_svm_map
Use of kmap_atomic disables preemption but if we run in
shadow-shadow mode the vmrun emulation executes kvm_set_cr3
which might sleep or fault. So use kmap instead for
nested_svm_map.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:34:07 +03:00
Takuya Yoshikawa 0e4176a15f KVM: x86 emulator: Fix x86_emulate_insn() not to use the variable rc for non-X86EMUL values
This patch makes non-X86EMUL_* family functions not to use
the variable rc.

Be sure that this changes nothing but makes the purpose of
the variable rc clearer.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:50 +03:00
Takuya Yoshikawa 1b30eaa846 KVM: x86 emulator: X86EMUL macro replacements: x86_emulate_insn() and its helpers
This patch just replaces integer values used inside
x86_emulate_insn() and its helper functions to X86EMUL_*.

The purpose of this is to make it clear what will happen
when the variable rc is compared to X86EMUL_* at the end
of x86_emulate_insn().

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:46 +03:00
Takuya Yoshikawa 3e2815e9fa KVM: x86 emulator: X86EMUL macro replacements: from do_fetch_insn_byte() to x86_decode_insn()
This patch just replaces the integer values used inside x86's
decode functions to X86EMUL_*.

By this patch, it becomes clearer that we are using X86EMUL_*
value propagated from ops->read_std() in do_fetch_insn_byte().

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:43 +03:00
Gleb Natapov 1161624f15 KVM: inject #UD in 64bit mode from instruction that are not valid there
Some instruction are obsolete in a long mode. Inject #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:40 +03:00
Gleb Natapov 89a27f4d0e KVM: use desc_ptr struct instead of kvm private descriptor_table
x86 arch defines desc_ptr for idt/gdt pointers, no need to define
another structure in kvm code.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-25 12:27:28 +03:00
Jan Kiszka e8861cfe2c KVM: x86: Fix TSS size check for 16-bit tasks
A 16-bit TSS is only 44 bytes long. So make sure to test for the correct
size on task switch.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-21 13:51:42 +03:00
Takuya Yoshikawa 87bf6e7de1 KVM: fix the handling of dirty bitmaps to avoid overflows
Int is not long enough to store the size of a dirty bitmap.

This patch fixes this problem with the introduction of a wrapper
function to calculate the sizes of dirty bitmaps.

Note: in mark_page_dirty(), we have to consider the fact that
  __set_bit() takes the offset as int, not long.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-04-20 13:06:55 +03:00
Xiao Guangrong 77662e0028 KVM: MMU: fix kvm_mmu_zap_page() and its calling path
This patch fix:

- calculate zapped page number properly in mmu_zap_unsync_children()
- calculate freeed page number properly kvm_mmu_change_mmu_pages()
- if zapped children page it shoud restart hlist walking

KVM-Stable-Tag.
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-04-20 12:59:32 +03:00
Avi Kivity 78ac8b47c5 KVM: VMX: Save/restore rflags.vm correctly in real mode
Currently we set eflags.vm unconditionally when entering real mode emulation
through virtual-8086 mode, and clear it unconditionally when we enter protected
mode.  The means that the following sequence

  KVM_SET_REGS  (rflags.vm=1)
  KVM_SET_SREGS (cr0.pe=1)

Ends up with rflags.vm clear due to KVM_SET_SREGS triggering enter_pmode().

Fix by shadowing rflags.vm (and rflags.iopl) correctly while in real mode:
reads and writes to those bits access a shadow register instead of the actual
register.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-04-20 12:59:31 +03:00
Andre Przywara 114be429c8 KVM: allow bit 10 to be cleared in MSR_IA32_MC4_CTL
There is a quirk for AMD K8 CPUs in many Linux kernels (see
arch/x86/kernel/cpu/mcheck/mce.c:__mcheck_cpu_apply_quirks()) that
clears bit 10 in that MCE related MSR. KVM can only cope with all
zeros or all ones, so it will inject a #GP into the guest, which
will let it panic.
So lets add a quirk to the quirk and ignore this single cleared bit.
This fixes -cpu kvm64 on all machines and -cpu host on K8 machines
with some guest Linux kernels.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-20 12:59:31 +03:00
Avi Kivity d6a23895aa KVM: Don't spam kernel log when injecting exceptions due to bad cr writes
These are guest-triggerable.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-20 12:55:05 +03:00
Takuya Yoshikawa b7af404338 KVM: SVM: Fix memory leaks that happen when svm_create_vcpu() fails
svm_create_vcpu() does not free the pages allocated during the creation
when it fails to complete the allocations. This patch fixes it.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-20 12:55:04 +03:00
Gleb Natapov 7567cae105 KVM: take srcu lock before call to complete_pio()
complete_pio() may use slot table which is protected by srcu.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-20 12:55:04 +03:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Linus Torvalds c812a51d11 Merge branch 'kvm-updates/2.6.34' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.34' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (145 commits)
  KVM: x86: Add KVM_CAP_X86_ROBUST_SINGLESTEP
  KVM: VMX: Update instruction length on intercepted BP
  KVM: Fix emulate_sys[call, enter, exit]()'s fault handling
  KVM: Fix segment descriptor loading
  KVM: Fix load_guest_segment_descriptor() to inject page fault
  KVM: x86 emulator: Forbid modifying CS segment register by mov instruction
  KVM: Convert kvm->requests_lock to raw_spinlock_t
  KVM: Convert i8254/i8259 locks to raw_spinlocks
  KVM: x86 emulator: disallow opcode 82 in 64-bit mode
  KVM: x86 emulator: code style cleanup
  KVM: Plan obsolescence of kernel allocated slots, paravirt mmu
  KVM: x86 emulator: Add LOCK prefix validity checking
  KVM: x86 emulator: Check CPL level during privilege instruction emulation
  KVM: x86 emulator: Fix popf emulation
  KVM: x86 emulator: Check IOPL level during io instruction emulation
  KVM: x86 emulator: fix memory access during x86 emulation
  KVM: x86 emulator: Add Virtual-8086 mode of emulation
  KVM: x86 emulator: Add group9 instruction decoding
  KVM: x86 emulator: Add group8 instruction decoding
  KVM: do not store wqh in irqfd
  ...

Trivial conflicts in Documentation/feature-removal-schedule.txt
2010-03-05 13:12:34 -08:00
Jan Kiszka d2be1651b7 KVM: x86: Add KVM_CAP_X86_ROBUST_SINGLESTEP
This marks the guest single-step API improvement of 94fe45da and
91586a3b with a capability flag to allow reliable detection by user
space.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: stable@kernel.org (2.6.33)
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:14 -03:00
Jan Kiszka c573cd2293 KVM: VMX: Update instruction length on intercepted BP
We intercept #BP while in guest debugging mode. As VM exits due to
intercepted exceptions do not necessarily come with valid
idt_vectoring, we have to update event_exit_inst_len explicitly in such
cases. At least in the absence of migration, this ensures that
re-injections of #BP will find and use the correct instruction length.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: stable@kernel.org (2.6.32, 2.6.33)
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:14 -03:00
Takuya Yoshikawa e54cfa97a9 KVM: Fix emulate_sys[call, enter, exit]()'s fault handling
This patch fixes emulate_syscall(), emulate_sysenter() and
emulate_sysexit() to handle injected faults properly.

Even though original code injects faults in these functions,
we cannot handle these unless we use the different return
value from the UNHANDLEABLE case. So this patch use X86EMUL_*
codes instead of -1 and 0 and makes x86_emulate_insn() to
handle these propagated faults.

Be sure that, in x86_emulate_insn(), goto cannot_emulate and
goto done with rc equals X86EMUL_UNHANDLEABLE have same effect.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:14 -03:00
Gleb Natapov c697518a86 KVM: Fix segment descriptor loading
Add proper error and permission checking. This patch also change task
switching code to load segment selectors before segment descriptors, like
SDM requires, otherwise permission checking during segment descriptor
loading will be incorrect.

Cc: stable@kernel.org (2.6.33, 2.6.32)
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:14 -03:00
Takuya Yoshikawa 6f550484a1 KVM: Fix load_guest_segment_descriptor() to inject page fault
This patch injects page fault when reading descriptor in
load_guest_segment_descriptor() fails with FAULT.

Effects of this injection: This function is used by
kvm_load_segment_descriptor() which is necessary for the
following instructions:

 - mov seg,r/m16
 - jmp far
 - pop ?s

This patch makes it possible to emulate the page faults
generated by these instructions. But be sure that unless
we change the kvm_load_segment_descriptor()'s ret value
propagation this patch has no effect.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:13 -03:00
Gleb Natapov 8b9f44140b KVM: x86 emulator: Forbid modifying CS segment register by mov instruction
Inject #UD if guest attempts to do so. This is in accordance to Intel
SDM.

Cc: stable@kernel.org (2.6.33, 2.6.32)
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:13 -03:00
Thomas Gleixner fa8273e954 KVM: Convert i8254/i8259 locks to raw_spinlocks
The i8254/i8259 locks need to be real spinlocks on preempt-rt. Convert
them to raw_spinlock. No change for !RT kernels.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:12 -03:00
Gleb Natapov e424e19183 KVM: x86 emulator: disallow opcode 82 in 64-bit mode
Instructions with opcode 82 are not valid in 64 bit mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:12 -03:00
Wei Yongjun 1d327eac3c KVM: x86 emulator: code style cleanup
Just remove redundant semicolon.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:12 -03:00
Gleb Natapov d380a5e402 KVM: x86 emulator: Add LOCK prefix validity checking
Instructions which are not allowed to have LOCK prefix should
generate #UD if one is used.

[avi: fold opcode 82 fix from another patch]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov e92805ac12 KVM: x86 emulator: Check CPL level during privilege instruction emulation
Add CPL checking in case emulator is tricked into emulating
privilege instruction from userspace.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov d4c6a1549c KVM: x86 emulator: Fix popf emulation
POPF behaves differently depending on current CPU mode. Emulate correct
logic to prevent guest from changing flags that it can't change otherwise.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov f850e2e603 KVM: x86 emulator: Check IOPL level during io instruction emulation
Make emulator check that vcpu is allowed to execute IN, INS, OUT,
OUTS, CLI, STI.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov 1871c6020d KVM: x86 emulator: fix memory access during x86 emulation
Currently when x86 emulator needs to access memory, page walk is done with
broadest permission possible, so if emulated instruction was executed
by userspace process it can still access kernel memory. Fix that by
providing correct memory access to page walker during emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov a004475567 KVM: x86 emulator: Add Virtual-8086 mode of emulation
For some instructions CPU behaves differently for real-mode and
virtual 8086. Let emulator know which mode cpu is in, so it will
not poke into vcpu state directly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:11 -03:00
Gleb Natapov 60a29d4ea4 KVM: x86 emulator: Add group9 instruction decoding
Use groups mechanism to decode 0F C7 instructions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:10 -03:00
Gleb Natapov 2db2c2eb62 KVM: x86 emulator: Add group8 instruction decoding
Use groups mechanism to decode 0F BA instructions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:10 -03:00
Wei Yongjun 72bb2fcd23 KVM: cleanup the failure path of KVM_CREATE_IRQCHIP ioctrl
If we fail to init ioapic device or the fail to setup the default irq
routing, the device register by kvm_create_pic() and kvm_ioapic_init()
remain unregister. This patch fixed to do this.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:10 -03:00
Wei Yongjun d225f53b76 KVM: PIT: unregister kvm irq notifier if fail to create pit
If fail to create pit, we should unregister kvm irq notifier
which register in kvm_create_pit().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:09 -03:00
Sheng Yang a19a6d1131 KVM: VMX: Rename VMX_EPT_IGMT_BIT to VMX_EPT_IPAT_BIT
Following the new SDM. Now the bit is named "Ignore PAT memory type".

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:09 -03:00
Avi Kivity 90bb6fc556 KVM: MMU: Add tracepoint for guest page aging
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:09 -03:00
Takuya Yoshikawa 1976d2d2c9 KVM: Remove redundant reading of rax on OUT instructions
kvm_emulate_pio() and complete_pio() both read out the
RAX register value and copy it to a place into which
the value read out from the port will be copied later.

This patch removes this redundancy.

/*** snippet from arch/x86/kvm/x86.c ***/
int complete_pio(struct kvm_vcpu *vcpu)
{
	...
	if (!io->string) {
		if (io->in) {
			val = kvm_register_read(vcpu, VCPU_REGS_RAX);
			memcpy(&val, vcpu->arch.pio_data, io->size);
			kvm_register_write(vcpu, VCPU_REGS_RAX, val);
		}
	...

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:09 -03:00
Rik van Riel 6316e1c8c6 KVM: VMX: emulate accessed bit for EPT
Currently KVM pretends that pages with EPT mappings never got
accessed.  This has some side effects in the VM, like swapping
out actively used guest pages and needlessly breaking up actively
used hugepages.

We can avoid those very costly side effects by emulating the
accessed bit for EPT PTEs, which should only be slightly costly
because pages pass through page_referenced infrequently.

TLB flushing is taken care of by kvm_mmu_notifier_clear_flush_young().

This seems to help prevent KVM guests from being swapped out when
they should not on my system.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:08 -03:00
Joerg Roedel 8f0b1ab6fb KVM: Introduce kvm_host_page_size
This patch introduces a generic function to find out the
host page size for a given gfn. This function is needed by
the kvm iommu code. This patch also simplifies the x86
host_mapping_level function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:08 -03:00
Julia Lawall c45b4fd416 KVM: VMX: Remove redundant test in vmx_set_efer()
msr was tested above, so the second test is not needed.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
expression *x;
expression e;
identifier l;
@@

if (x == NULL || ...) {
    ... when forall
    return ...; }
... when != goto l;
    when != x = e
    when != &x
*x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:07 -03:00