Commit Graph

1143 Commits

Author SHA1 Message Date
Gleb Natapov
acb5451789 KVM: prevent spurious exit to userspace during task switch emulation.
If kvm_task_switch() fails code exits to userspace without specifying
exit reason, so the previous exit reason is reused by userspace. Fix
this by specifying exit reason correctly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:55 +03:00
Xiao Guangrong
6b18493d60 KVM: MMU: remove unused parameter in mmu_parent_walk()
'vcpu' is unused, remove it

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:53 +03:00
Xiao Guangrong
1b8c7934a4 KVM: MMU: remove unused struct kvm_unsync_walk
Remove 'struct kvm_unsync_walk' since it's not used.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:50 +03:00
Gleb Natapov
19d0443726 KVM: fix emulator_task_switch() return value.
emulator_task_switch() should return -1 for failure and 0 for success to
the caller, just like x86_emulate_insn() does.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:49 +03:00
Avi Kivity
5b7e0102ae KVM: MMU: Replace role.glevels with role.cr4_pae
There is no real distinction between glevels=3 and glevels=4; both have
exactly the same format and the code is treated exactly the same way.  Drop
role.glevels and replace is with role.cr4_pae (which is meaningful).  This
simplifies the code a bit.

As a side effect, it allows sharing shadow page tables between pae and
longmode guest page tables at the same guest page.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:47 +03:00
Jan Kiszka
e269fb2189 KVM: x86: Push potential exception error code on task switches
When a fault triggers a task switch, the error code, if existent, has to
be pushed on the new task's stack. Implement the missing bits.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:46 +03:00
Jan Kiszka
0760d44868 KVM: x86: Terminate early if task_switch_16/32 failed
Stop the switch immediately if task_switch_16/32 returned an error. Only
if that step succeeded, the switch should actually take place and update
any register states.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:44 +03:00
Gleb Natapov
8f6abd06f5 KVM: x86: get rid of mmu_only parameter in emulator_write_emulated()
We can call kvm_mmu_pte_write() directly from
emulator_cmpxchg_emulated() instead of passing mmu_only down to
emulator_write_emulated_onepage() and call it there.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:43 +03:00
Gleb Natapov
020df0794f KVM: move DR register access handling into generic code
Currently both SVM and VMX have their own DR handling code. Move it to
x86.c.

Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:39 +03:00
Andre Przywara
6bc31bdc55 KVM: SVM: implement NEXTRIPsave SVM feature
On SVM we set the instruction length of skipped instructions
to hard-coded, well known values, which could be wrong when (bogus,
but valid) prefixes (REX, segment override) are used.
Newer AMD processors (Fam10h 45nm and better, aka. PhenomII or
AthlonII) have an explicit NEXTRIP field in the VMCB containing the
desired information.
Since it is cheap to do so, we use this field to override the guessed
value on newer processors.
A fix for older CPUs would be rather expensive, as it would require
to fetch and partially decode the instruction. As the problem is not
a security issue and needs special, handcrafted code to trigger
(no compiler will ever generate such code), I omit a fix for older
CPUs.
If someone is interested, I have both a patch for these CPUs as well as
demo code triggering this issue: It segfaults under KVM, but runs
perfectly on native Linux.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:38 +03:00
Avi Kivity
f7a711971e KVM: Fix MAXPHYADDR calculation when cpuid does not support it
MAXPHYADDR is derived from cpuid 0x80000008, but when that isn't present, we
get some random value.

Fix by checking first that cpuid 0x80000008 is supported.

Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:36 +03:00
Avi Kivity
e46479f852 KVM: Trace emulated instructions
Log emulated instructions in ftrace, especially if they failed.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:35 +03:00
Avi Kivity
2fb53ad811 KVM: x86 emulator: Don't overwrite decode cache
Currently if we an instruction spans a page boundary, when we fetch the
second half we overwrite the first half.  This prevents us from tracing
the full instruction opcodes.

Fix by appending the second half to the first.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:33 +03:00
Xiao Guangrong
24222c2fec KVM: MMU: remove unnecessary NX check in walk_addr
After is_rsvd_bits_set() checks, EFER.NXE must be enabled if NX bit is seted

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:30 +03:00
Xiao Guangrong
f84cbb0561 KVM: MMU: remove unused field
kvm_mmu_page.oos_link is not used, so remove it

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:29 +03:00
Xiao Guangrong
805d32dea4 KVM: MMU: cleanup/fix mmu audit code
This patch does:
- 'sp' parameter in inspect_spte_fn() is not used, so remove it
- fix 'kvm' and 'slots' is not defined in count_rmaps()
- fix a bug in inspect_spte_has_rmap()

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:27 +03:00
Avi Kivity
84b0c8c6a6 KVM: MMU: Disassociate direct maps from guest levels
Direct maps are linear translations for a section of memory, used for
real mode or with large pages.  As such, they are independent of the guest
levels.

Teach the mmu about this by making page->role.glevels = 0 for direct maps.
This allows direct maps to be shared among real mode and the various paging
modes.

Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:44 +03:00
Xiao Guangrong
f815bce894 KVM: MMU: check reserved bits only if CR4.PSE=1 or CR4.PAE=1
- Check reserved bits only if CR4.PAE=1 or CR4.PSE=1 when guest #PF occurs
- Fix a typo in reset_rsvds_bits_mask()

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:42 +03:00
Marcelo Tosatti
041b1359a2 KVM: x86: document KVM_REQ_PENDING_TIMER usage
Document that KVM_REQ_PENDING_TIMER is implicitly used during guest
entry.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:40 +03:00
Gleb Natapov
de3e6480f7 KVM: x86 emulator: fix unlocked CMPXCHG8B emulation
When CMPXCHG8B is executed without LOCK prefix it is racy. Preserve this
behaviour in emulator too.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:38 +03:00
Gleb Natapov
6550e1f165 KVM: x86 emulator: add decoding of CMPXCHG8B dst operand
Decode CMPXCHG8B destination operand in decoding stage. Fixes regression
introduced by "If LOCK prefix is used dest arg should be memory" commit.
This commit relies on dst operand be decoded at the beginning of an
instruction emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:37 +03:00
Gleb Natapov
482ac18ae2 KVM: x86 emulator: commit rflags as part of registers commit
Make sure that rflags is committed only after successful instruction
emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:35 +03:00
Jan Kiszka
9749a6c0f0 KVM: x86: Fix 32-bit build breakage due to typo
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:16:34 +03:00
Gleb Natapov
92bf9748b5 KVM: small kvm_arch_vcpu_ioctl_run() cleanup.
Unify all conditions that get us back into emulator after returning from
userspace.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:32 +03:00
Gleb Natapov
7b262e90fc KVM: x86 emulator: introduce pio in string read ahead.
To optimize "rep ins" instruction do IO in big chunks ahead of time
instead of doing it only when required during instruction emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:31 +03:00
Gleb Natapov
5cd21917da KVM: x86 emulator: restart string instruction without going back to a guest.
Currently when string instruction is only partially complete we go back
to a guest mode, guest tries to reexecute instruction and exits again
and at this point emulation continues. Avoid all of this by restarting
instruction without going back to a guest mode, but return to a guest
mode each 1024 iterations to allow interrupt injection. Pending
exception causes immediate guest entry too.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:29 +03:00
Gleb Natapov
cb404fe089 KVM: x86 emulator: remove saved_eip
c->eip is never written back in case of emulation failure, so no need to
set it to old value.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:28 +03:00
Gleb Natapov
7972995b0c KVM: x86 emulator: Move string pio emulation into emulator.c
Currently emulation is done outside of emulator so things like doing
ins/outs to/from mmio are broken it also makes it hard (if not impossible)
to implement single stepping in the future. The implementation in this
patch is not efficient since it exits to userspace for each IO while
previous implementation did 'ins' in batches. Further patch that
implements pio in string read ahead address this problem.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:26 +03:00
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
Gleb Natapov
d9271123a4 KVM: x86 emulator: during rep emulation decrement ECX only if emulation succeeded
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:23 +03:00
Gleb Natapov
a682e35449 KVM: x86 emulator: add decoding of X,Y parameters from Intel SDM
Add decoding of X,Y parameters from Intel SDM which are used by string
instruction to specify source and destination. Use this new decoding
to implement movs, cmps, stos, lods in a generic way.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:21 +03:00
Gleb Natapov
69f55cb11e KVM: x86 emulator: populate OP_MEM operand during decoding.
All struct operand fields are initialized during decoding for all
operand types except OP_MEM, but there is no reason for that. Move
OP_MEM operand initialization into decoding stage for consistency.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:20 +03:00
Gleb Natapov
ceffb45972 KVM: Use task switch from emulator.c
Remove old task switch code from x86.c

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:18 +03:00
Gleb Natapov
2e873022f5 KVM: x86 emulator: Use load_segment_descriptor() instead of kvm_load_segment_descriptor()
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:17 +03:00
Gleb Natapov
38ba30ba51 KVM: x86 emulator: Emulate task switch in emulator.c
Implement emulation of 16/32 bit task switch in emulator.c

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:15 +03:00
Gleb Natapov
2dafc6c234 KVM: x86 emulator: Provide more callbacks for x86 emulator.
Provide get_cached_descriptor(), set_cached_descriptor(),
get_segment_selector(), set_segment_selector(), get_gdt(),
write_std() callbacks.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:14 +03:00
Gleb Natapov
aca06a8307 KVM: x86 emulator: cleanup grp3 return value
When x86_emulate_insn() does not know how to emulate instruction it
exits via cannot_emulate label in all cases except when emulating
grp3. Fix that.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:12 +03:00
Gleb Natapov
a41ffb7540 KVM: x86 emulator: If LOCK prefix is used dest arg should be memory.
If LOCK prefix is used dest arg should be memory, otherwise instruction
should generate #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:11 +03:00
Gleb Natapov
fd5253658b KVM: x86 emulator: do not call writeback if msr access fails.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:09 +03:00
Gleb Natapov
2e901c4cf4 KVM: x86 emulator: fix return values of syscall/sysenter/sysexit emulations
Return X86EMUL_PROPAGATE_FAULT is fault was injected. Also inject #UD
for those instruction when appropriate.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:08 +03:00
Gleb Natapov
1e470be5a1 KVM: x86 emulator: fix mov dr to inject #UD when needed.
If CR4.DE=1 access to registers DR4/DR5 cause #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:06 +03:00
Gleb Natapov
6aebfa6ea7 KVM: x86 emulator: inject #UD on access to non-existing CR
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:05 +03:00
Gleb Natapov
ab8557b2b3 KVM: x86 emulator: 0f (20|21|22|23) ignore mod bits.
Resent spec says that for 0f (20|21|22|23) the 2 bits in the mod field
are ignored. Interestingly enough older spec says that 11 is only valid
encoding.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:03 +03:00
Gleb Natapov
6e1e5ffee8 KVM: x86 emulator: fix 0f 01 /5 emulation
It is undefined and should generate #UD.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:02 +03:00
Gleb Natapov
5e3ae6c540 KVM: x86 emulator: fix mov r/m, sreg emulation.
mov r/m, sreg generates #UD ins sreg is incorrect.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:16:00 +03:00
Gleb Natapov
063db061b9 KVM: Provide current eip as part of emulator context.
Eliminate the need to call back into KVM to get it from emulator.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:59 +03:00
Gleb Natapov
9c5372445c KVM: Provide x86_emulate_ctxt callback to get current cpl
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:57 +03:00
Gleb Natapov
93a152be5a KVM: remove realmode_lmsw function.
Use (get|set)_cr callback to emulate lmsw inside emulator.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:56 +03:00
Gleb Natapov
52a4661737 KVM: Provide callback to get/set control registers in emulator ops.
Use this callback instead of directly call kvm function. Also rename
realmode_(set|get)_cr to emulator_(set|get)_cr since function has nothing
to do with real mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:15:54 +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
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
Jan Kiszka
f8c5fae166 KVM: VMX: blocked-by-sti must not defer NMI injections
As the processor may not consider GUEST_INTR_STATE_STI as a reason for
blocking NMI, it could return immediately with EXIT_REASON_NMI_WINDOW
when we asked for it. But as we consider this state as NMI-blocking, we
can run into an endless loop.

Resolve this by allowing NMI injection if just GUEST_INTR_STATE_STI is
active (originally suggested by Gleb). Intel confirmed that this is
safe, the processor will never complain about NMI injection in this
state.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
KVM-Stable-Tag
Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-13 01:31:37 -03:00
Dongxiao Xu
fe19c5a46b KVM: x86: Call vcpu_load and vcpu_put in cpuid_update
cpuid_update may operate VMCS, so vcpu_load() and vcpu_put()
should be called to ensure correctness.

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-13 01:31:02 -03:00
Joerg Roedel
061e2fd168 KVM: SVM: Fix wrong intercept masks on 32 bit
This patch makes KVM on 32 bit SVM working again by
correcting the masks used for iret interception. With the
wrong masks the upper 32 bits of the intercepts are masked
out which leaves vmrun unintercepted. This is not legal on
svm and the vmrun fails.
Bug was introduced by commits 95ba827313 and 3cfc3092.

Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-13 01:24:08 -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