Commit graph

242 commits

Author SHA1 Message Date
Gleb Natapov
cf8f70bfe3 KVM: x86 emulator: fix in/out emulation.
in/out emulation is broken now. The breakage is different depending
on where IO device resides. If it is in userspace emulator reports
emulation failure since it incorrectly interprets kvm_emulate_pio()
return value. If IO device is in the kernel emulation of 'in' will do
nothing since kvm_emulate_pio() stores result directly into vcpu
registers, so emulator will overwrite result of emulation during
commit of shadowed register.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:25 +03:00
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
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
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
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
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
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
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
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
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
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
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
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
Avi Kivity
ebcbab4c03 KVM: VMX: Wire up .fpu_activate() callback
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:07 -03:00
Gui Jianfeng
6d3e435e70 KVM: VMX: Remove redundant check in vm_need_virtualize_apic_accesses()
flexpriority_enabled implies cpu_has_vmx_virtualize_apic_accesses() returning
true, so we don't need this check here.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:06 -03:00
Avi Kivity
59200273c4 KVM: Trace failed msr reads and writes
Record failed msrs reads and writes, and the fact that they failed as well.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:06 -03:00
Avi Kivity
81231c698a KVM: VMX: Pass cr0.mp through to the guest when the fpu is active
When cr0.mp is clear, the guest doesn't expect a #NM in response to
a WAIT instruction.  Because we always keep cr0.mp set, it will get
a #NM, and potentially be confused.

Fix by keeping cr0.mp set only when the fpu is inactive, and passing
it through when inactive.

Reported-by: Lorenzo Martignoni <martignlo@gmail.com>
Analyzed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:06 -03:00
Avi Kivity
f6801dff23 KVM: Rename vcpu->shadow_efer to efer
None of the other registers have the shadow_ prefix.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:04 -03:00
Avi Kivity
3eeb3288bc KVM: Add a helper for checking if the guest is in protected mode
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:04 -03:00
Avi Kivity
6b52d18605 KVM: Activate fpu on clts
Assume that if the guest executes clts, it knows what it's doing, and load the
guest fpu to prevent an #NM exception.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:04 -03:00
Jan Kiszka
fd7373cce7 KVM: VMX: Clean up DR6 emulation
As we trap all debug register accesses, we do not need to switch real
DR6 at all. Clean up update_exception_bitmap at this chance, too.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:02 -03:00
Jan Kiszka
138ac8d88f KVM: VMX: Fix emulation of DR4 and DR5
Make sure DR4 and DR5 are aliased to DR6 and DR7, respectively, if
CR4.DE is not set.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -03:00
Jan Kiszka
f248341529 KVM: VMX: Fix exceptions of mov to dr
Injecting GP without an error code is a bad idea (causes unhandled guest
exits). Moreover, we must not skip the instruction if we injected an
exception.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -03:00
Sheng Yang
7062dcaa36 KVM: VMX: Remove emulation failure report
As Avi noted:

>There are two problems with the kernel failure report.  First, it
>doesn't report enough data - registers, surrounding instructions, etc.
>that are needed to explain what is going on.  Second, it can flood
>dmesg, which is a pretty bad thing to do.

So we remove the emulation failure report in handle_invalid_guest_state(),
and would inspected the guest using userspace tool in the future.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:36:01 -03:00
Avi Kivity
edcafe3c5a KVM: VMX: Give the guest ownership of cr0.ts when the fpu is active
If the guest fpu is loaded, there is nothing interesing about cr0.ts; let
the guest play with it as it will.  This makes context switches between fpu
intensive guest processes faster, as we won't trap the clts and cr0 write
instructions.

[marcelo: fix cr0 read shadow update on fpu deactivation; kills F8 install]

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity
02daab21d9 KVM: Lazify fpu activation and deactivation
Defer fpu deactivation as much as possible - if the guest fpu is loaded, keep
it loaded until the next heavyweight exit (where we are forced to unload it).
This reduces unnecessary exits.

We also defer fpu activation on clts; while clts signals the intent to use the
fpu, we can't be sure the guest will actually use it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity
e8467fda83 KVM: VMX: Allow the guest to own some cr0 bits
We will use this later to give the guest ownership of cr0.ts.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity
4d4ec08745 KVM: Replace read accesses of vcpu->arch.cr0 by an accessor
Since we'd like to allow the guest to own a few bits of cr0 at times, we need
to know when we access those bits.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Avi Kivity
a1f83a74fe KVM: VMX: trace clts and lmsw instructions as cr accesses
clts writes cr0.ts; lmsw writes cr0[0:15] - record that in ftrace.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:50 -03:00
Sheng Yang
878403b788 KVM: VMX: Enable EPT 1GB page support
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:46 -03:00
Sheng Yang
17cc393596 KVM: x86: Rename gb_page_enable() to get_lpage_level() in kvm_x86_ops
Then the callback can provide the maximum supported large page level, which
is more flexible.

Also move the gb page support into x86_64 specific.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:46 -03:00
Avi Kivity
f4c9e87c83 KVM: Fill out ftrace exit reason strings
Some exit reasons missed their strings; fill out the table.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:45 -03:00
Marcelo Tosatti
79fac95ecf KVM: convert slots_lock to a mutex
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:45 -03:00
Marcelo Tosatti
f656ce0185 KVM: switch vcpu context to use SRCU
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:45 -03:00
Marcelo Tosatti
bc6678a33d KVM: introduce kvm->srcu and convert kvm_set_memory_region to SRCU update
Use two steps for memslot deletion: mark the slot invalid (which stops
instantiation of new shadow pages for that slot, but allows destruction),
then instantiate the new empty slot.

Also simplifies kvm_handle_hva locking.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:44 -03:00
Marcelo Tosatti
46a26bf557 KVM: modify memslots layout in struct kvm
Have a pointer to an allocated region inside struct kvm.

[alex: fix ppc book 3s]

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-03-01 12:35:43 -03:00
Sheng Yang
4e47c7a6d7 KVM: VMX: Add instruction rdtscp support for guest
Before enabling, execution of "rdtscp" in guest would result in #UD.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Sheng Yang
0e85188049 KVM: Add cpuid_update() callback to kvm_x86_ops
Sometime, we need to adjust some state in order to reflect guest CPUID
setting, e.g. if we don't expose rdtscp to guest, we won't want to enable
it on hardware. cpuid_update() is introduced for this purpose.

Also export kvm_find_cpuid_entry() for later use.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Sheng Yang
8a7e3f01e6 KVM: VMX: Remove redundant variable
It's no longer necessary.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Avi Kivity
bc23008b61 KVM: VMX: Fold ept_update_paging_mode_cr4() into its caller
ept_update_paging_mode_cr4() accesses vcpu->arch.cr4 directly, which usually
needs to be accessed via kvm_read_cr4().  In this case, we can't, since cr4
is in the process of being updated.  Instead of adding inane comments, fold
the function into its caller (vmx_set_cr4), so it can use the not-yet-committed
cr4 directly.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:40 -03:00
Avi Kivity
ce03e4f21a KVM: VMX: When using ept, allow the guest to own cr4.pge
We make no use of cr4.pge if ept is enabled, but the guest does (to flush
global mappings, as with vmap()), so give the guest ownership of this bit.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity
4c38609ac5 KVM: VMX: Make guest cr4 mask more conservative
Instead of specifying the bits which we want to trap on, specify the bits
which we allow the guest to change transparently.  This is safer wrt future
changes to cr4.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity
fc78f51938 KVM: Add accessor for reading cr4 (or some bits of cr4)
Some bits of cr4 can be owned by the guest on vmx, so when we read them,
we copy them to the vcpu structure.  In preparation for making the set of
guest-owned bits dynamic, use helpers to access these bits so we don't need
to know where the bit resides.

No changes to svm since all bits are host-owned there.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity
cdc0e24456 KVM: VMX: Move some cr[04] related constants to vmx.c
They have no place in common code.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Sheng Yang
59708670b6 KVM: VMX: Trap and invalid MWAIT/MONITOR instruction
We don't support these instructions, but guest can execute them even if the
feature('monitor') haven't been exposed in CPUID. So we would trap and inject
a #UD if guest try this way.

Cc: stable@kernel.org
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:39 -03:00
Avi Kivity
d5696725b2 KVM: VMX: Fix comparison of guest efer with stale host value
update_transition_efer() masks out some efer bits when deciding whether
to switch the msr during guest entry; for example, NX is emulated using the
mmu so we don't need to disable it, and LMA/LME are handled by the hardware.

However, with shared msrs, the comparison is made against a stale value;
at the time of the guest switch we may be running with another guest's efer.

Fix by deferring the mask/compare to the actual point of guest entry.

Noted by Marcelo.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:34:20 +02:00
Sheng Yang
046d87103a KVM: VMX: Disable unrestricted guest when EPT disabled
Otherwise would cause VMEntry failure when using ept=0 on unrestricted guest
supported processors.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-12-03 09:32:25 +02:00
Jan Kiszka
3cfc3092f4 KVM: x86: Add KVM_GET/SET_VCPU_EVENTS
This new IOCTL exports all yet user-invisible states related to
exceptions, interrupts, and NMIs. Together with appropriate user space
changes, this fixes sporadic problems of vmsave/restore, live migration
and system reset.

[avi: future-proof abi by adding a flags field]

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:25 +02:00
Avi Kivity
65ac726404 KVM: VMX: Report unexpected simultaneous exceptions as internal errors
These happen when we trap an exception when another exception is being
delivered; we only expect these with MCEs and page faults.  If something
unexpected happens, things probably went south and we're better off reporting
an internal error and freezing.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:24 +02:00
Avi Kivity
a9c7399d6c KVM: Allow internal errors reported to userspace to carry extra data
Usually userspace will freeze the guest so we can inspect it, but some
internal state is not available.  Add extra data to internal error
reporting so we can expose it to the debugger.  Extra data is specific
to the suberror.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-03 09:32:24 +02:00