Commit graph

10379 commits

Author SHA1 Message Date
Avi Kivity
9beeaa2d68 Merge branch 'perf'
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-05-17 12:17:58 +03:00
Xiao Guangrong
3246af0ece KVM: MMU: cleanup for hlist walk restart
Quote from Avi:

|Just change the assignment to a 'goto restart;' please,
|I don't like playing with list_for_each internals.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:56 +03:00
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
0571d366e0 KVM: MMU: reduce 'struct kvm_mmu_page' size
Define 'multimapped' as 'bool'.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-05-17 12:17:52 +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