Pekka Enberg [Mon, 9 May 2011 19:48:54 +0000 (22:48 +0300)]
KVM: Add documentation for KVM_CAP_NR_VCPUS
Document KVM_CAP_NR_VCPUS that can be used by the userspace to determine
maximum number of VCPUs it can create with the KVM_CREATE_VCPU ioctl.
Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Jan Kiszka <jan.kiszka@web.de> Signed-off-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Avi Kivity <avi@redhat.com>
Gleb Natapov [Wed, 4 May 2011 13:31:04 +0000 (16:31 +0300)]
KVM: make guest mode entry to be rcu quiescent state
KVM does not hold any references to rcu protected data when it switches
CPU into a guest mode. In fact switching to a guest mode is very similar
to exiting to userspase from rcu point of view. In addition CPU may stay
in a guest mode for quite a long time (up to one time slice). Lets treat
guest mode as quiescent state, just like we do with user-mode execution.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* commit '29ce831000081dd757d3116bf774aafffc4b6b20': (34 commits)
rcu: provide rcu_virt_note_context_switch() function.
rcu: get rid of signed overflow in check_cpu_stall()
rcu: optimize rcutiny
rcu: prevent call_rcu() from diving into rcu core if irqs disabled
rcu: further lower priority in rcu_yield()
rcu: introduce kfree_rcu()
rcu: fix spelling
rcu: call __rcu_read_unlock() in exit_rcu for tree RCU
rcu: Converge TINY_RCU expedited and normal boosting
rcu: remove useless ->boosted_this_gp field
rcu: code cleanups in TINY_RCU priority boosting.
rcu: Switch to this_cpu() primitives
rcu: Use WARN_ON_ONCE for DEBUG_OBJECTS_RCU_HEAD warnings
rcu: mark rcutorture boosting callback as being on-stack
rcu: add DEBUG_OBJECTS_RCU_HEAD check for alignment
rcu: Enable DEBUG_OBJECTS_RCU_HEAD from !PREEMPT
rcu: Add forward-progress diagnostic for per-CPU kthreads
rcu: add grace-period age and more kthread state to tracing
rcu: fix tracing bug thinko on boost-balk attribution
rcu: update tracing documentation for new rcutorture and rcuboost
...
Pulling in rcu_virt_note_context_switch().
Signed-off-by: Avi Kivity <avi@redhat.com>
* commit '29ce831000081dd757d3116bf774aafffc4b6b20': (34 commits)
rcu: provide rcu_virt_note_context_switch() function.
rcu: get rid of signed overflow in check_cpu_stall()
rcu: optimize rcutiny
rcu: prevent call_rcu() from diving into rcu core if irqs disabled
rcu: further lower priority in rcu_yield()
rcu: introduce kfree_rcu()
rcu: fix spelling
rcu: call __rcu_read_unlock() in exit_rcu for tree RCU
rcu: Converge TINY_RCU expedited and normal boosting
rcu: remove useless ->boosted_this_gp field
rcu: code cleanups in TINY_RCU priority boosting.
rcu: Switch to this_cpu() primitives
rcu: Use WARN_ON_ONCE for DEBUG_OBJECTS_RCU_HEAD warnings
rcu: mark rcutorture boosting callback as being on-stack
rcu: add DEBUG_OBJECTS_RCU_HEAD check for alignment
rcu: Enable DEBUG_OBJECTS_RCU_HEAD from !PREEMPT
rcu: Add forward-progress diagnostic for per-CPU kthreads
rcu: add grace-period age and more kthread state to tracing
rcu: fix tracing bug thinko on boost-balk attribution
rcu: update tracing documentation for new rcutorture and rcuboost
...
KVM: Validate userspace_addr of memslot when registered
This way, we can avoid checking the user space address many times when
we read the guest memory.
Although we can do the same for write if we check which slots are
writable, we do not care write now: reading the guest memory happens
more often than writing.
[avi: change VERIFY_READ to VERIFY_WRITE]
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
Stuart Yoder [Mon, 28 Mar 2011 20:01:56 +0000 (15:01 -0500)]
KVM: PPC: use ticks, not usecs, for exit timing
Convert to microseconds when displaying
(with fix from Bharat Bhushan <Bharat.Bhushan@freescale.com>).
This reduces rounding error with large quantities of short exits.
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Scott Wood [Mon, 28 Mar 2011 20:01:24 +0000 (15:01 -0500)]
KVM: PPC: fix exit accounting for SPRs, tlbwe, tlbsx
The exit type setting for mfspr/mtspr is moved from 44x to toplevel SPR
emulation. This enables it on e500, and makes sure that all SPRs
are covered.
Exit accounting for tlbwe and tlbsx is added to e500.
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Scott Wood [Tue, 29 Mar 2011 21:49:10 +0000 (16:49 -0500)]
KVM: PPC: e500: emulate SVR
Return the actual host SVR for now, as we already do for PVR. Eventually
we may support Qemu overriding PVR/SVR if the situation is appropriate,
once we implement KVM_SET_SREGS on e500.
Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
Avi Kivity [Wed, 27 Apr 2011 16:42:18 +0000 (19:42 +0300)]
KVM: VMX: Cache vmcs segment fields
Since the emulator now checks segment limits and access rights, it
generates a lot more accesses to the vmcs segment fields. Undo some
of the performance hit by cacheing those fields in a read-only cache
(the entire cache is invalidated on any write, or on guest exit).
Jeff Mahoney [Wed, 27 Apr 2011 18:06:07 +0000 (14:06 -0400)]
KVM: ia64: fix sparse warnings
This patch fixes some sparse warning about "dubious one-bit signed bitfield."
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Originally-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
The CPUIDs for Centaur are added, and then the features of
PadLock hardware engine on VIA CPU, such as "ace", "ace_en"
and so on, can be passed into the kvm guest.
Signed-off-by: Brilly Wu <brillywu@viatech.com.cn> Signed-off-by: Kary Jin <karyjin@viatech.com.cn> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Sun, 24 Apr 2011 09:25:50 +0000 (12:25 +0300)]
KVM: MMU: Add unlikely() annotations to walk_addr_generic()
walk_addr_generic() is a hot path and is also hard for the cpu to predict -
some of the parameters (fetch_fault in particular) vary wildly from
invocation to invocation.
Add unlikely() annotations where appropriate; all walk failures are
considered unlikely, as are cases where we have to mark the accessed or
dirty bit, as they are slow paths both in kvm and on real processors.
This patch makes the cmpxchg_gpte() function aware of the
difference between l1-gfns and l2-gfns when nested
virtualization is in use. This fixes a potential
data-corruption problem in the l1-guest and makes the code
work correct (at least as correct as the hardware which is
emulated in this code) again.
Cc: stable@kernel.org Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
The last_guest_tsc is used in vcpu_load to adjust the
tsc_offset since tsc-scaling is merged. So the
last_guest_tsc needs to be updated in vcpu_put instead of
the the last_host_tsc. This is fixed with this patch.
Reported-by: Jan Kiszka <jan.kiszka@web.de> Tested-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: SVM: Fix nested sel_cr0 intercept path with decode-assists
This patch fixes a bug in the nested-svm path when
decode-assists is available on the machine. After a
selective-cr0 intercept is detected the rip is advanced
unconditionally. This causes the l1-guest to continue
running with an l2-rip.
This bug was with the sel_cr0 unit-test on decode-assists
capable hardware.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Nelson Elhage [Wed, 13 Apr 2011 15:44:13 +0000 (11:44 -0400)]
KVM: x86 emulator: Handle wraparound in (cs_base + offset) when fetching insns
Currently, setting a large (i.e. negative) base address for %cs does not work on
a 64-bit host. The "JOS" teaching operating system, used by MIT and other
universities, relies on such segments while bootstrapping its way to full
virtual memory management.
Signed-off-by: Nelson Elhage <nelhage@ksplice.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Jeff Mahoney [Wed, 13 Apr 2011 01:30:17 +0000 (21:30 -0400)]
KVM: Fix off by one in kvm_for_each_vcpu iteration
This patch avoids gcc issuing the following warning when KVM_MAX_VCPUS=1:
warning: array subscript is above array bounds
kvm_for_each_vcpu currently checks to see if the index for the vcpu is
valid /after/ loading it. We don't run into problems because the address
is still inside the enclosing struct kvm and we never deference or write
to it, so this isn't a security issue.
The warning occurs when KVM_MAX_VCPUS=1 because the increment portion of
the loop will *always* cause the loop to load an invalid location since
++idx will always be > 0.
This patch moves the load so that the check occurs before the load and
we don't run into the compiler warning.
Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Avi Kivity <avi@redhat.com>
When doing a soft int, we need to bump eip before pushing it to
the stack. Otherwise we'll do the int a second time.
[apw@canonical.com: merged eip update as per Jan's recommendation.] Signed-off-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: x86 emulator: Make emulate_push() store the value directly
PUSH emulation stores the value by calling writeback() after setting
the dst operand appropriately in emulate_push().
This writeback() using dst is not needed at all because we know the
target is the stack. So this patch makes emulate_push() call, newly
introduced, segmented_write() directly.
By this, many inlined writeback()'s are removed.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
Jan Kiszka [Tue, 12 Apr 2011 23:27:55 +0000 (01:27 +0200)]
KVM: VMX: Ensure that vmx_create_vcpu always returns proper error
In case certain allocations fail, vmx_create_vcpu may return 0 as error
instead of a negative value encoded via ERR_PTR. This causes a NULL
pointer dereferencing later on in kvm_vm_ioctl_vcpu_create.
Gleb Natapov [Thu, 31 Mar 2011 10:06:41 +0000 (12:06 +0200)]
KVM: emulator: do not needlesly sync registers from emulator ctxt to vcpu
Currently we sync registers back and forth before/after exiting
to userspace for IO, but during IO device model shouldn't need to
read/write the registers, so we can as well skip those sync points. The
only exaception is broken vmware backdor interface. The new code sync
registers content during IO only if registers are read from/written to
by userspace in the middle of the IO operation and this almost never
happens in practise.
KVM: SVM: Fix fault-rip on vmsave/vmload emulation
When the emulation of vmload or vmsave fails because the
guest passed an unsupported physical address it gets an #GP
with rip pointing to the instruction after vmsave/vmload.
This is a bug and fixed by this patch.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 25 Mar 2011 08:44:51 +0000 (09:44 +0100)]
KVM: X86: Implement userspace interface to set virtual_tsc_khz
This patch implements two new vm-ioctls to get and set the
virtual_tsc_khz if the machine supports tsc-scaling. Setting
the tsc-frequency is only possible before userspace creates
any vcpu.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 25 Mar 2011 08:44:50 +0000 (09:44 +0100)]
KVM: X86: Delegate tsc-offset calculation to architecture code
With TSC scaling in SVM the tsc-offset needs to be
calculated differently. This patch propagates this
calculation into the architecture specific modules so that
this complexity can be handled there.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 25 Mar 2011 08:44:49 +0000 (09:44 +0100)]
KVM: X86: Implement call-back to propagate virtual_tsc_khz
This patch implements a call-back into the architecture code
to allow the propagation of changes to the virtual tsc_khz
of the vcpu.
On SVM it updates the tsc_ratio variable, on VMX it does
nothing.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Fri, 25 Mar 2011 08:44:48 +0000 (09:44 +0100)]
KVM: X86: Make tsc_delta calculation a function of guest tsc
The calculation of the tsc_delta value to ensure a
forward-going tsc for the guest is a function of the
host-tsc. This works as long as the guests tsc_khz is equal
to the hosts tsc_khz. With tsc-scaling hardware support this
is not longer true and the tsc_delta needs to be calculated
using guest_tsc values.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Tue, 5 Apr 2011 13:21:58 +0000 (16:21 +0300)]
KVM: x86 emulator: Re-add VendorSpecific tag to VMMCALL insn
VMMCALL needs the VendorSpecific tag so that #UD emulation
(called if a guest running on AMD was migrated to an Intel host)
is allowed to process the instruction.
The vcpu->mutex is used by kvm_ioctl_* (KVM_RUN etc) and same was
used when clearing the stats (in kvmppc_init_timing_stats()). What happens
is that when the guest is idle then it held the vcpu->mutx. While the
exiting timing process waits for guest to release the vcpu->mutex and
a hang state is reached.
Now using seprate lock for exit timing stats.
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com> Acked-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
This patch removes all the old code which handled the nested
selective cr0 write intercepts. This code was only in place
as a work-around until the instruction emulator is capable
of doing the same. This is the case with this patch-set and
so the code can be removed.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: SVM: Add intercept checks for SVM instructions
This patch adds the necessary code changes in the
instruction emulator and the extensions to svm.c to
implement intercept checks for the svm instructions.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
projects / linux-beck.git / log