As a bonus, an extra memory slot search can be eliminated when
is_self_change_mapping is true.
Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This will be passed to a function later.
Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Currently we always write the next_rip of the shadow vmcb to
the guests vmcb when we emulate a vmexit. This could confuse
the guest when its cpuid indicated no support for the
next_rip feature.

Fix this by only propagating next_rip if the guest actually
supports it.

Cc: Bandan Das <bsd@redhat.com>
Cc: Dirk Mueller <dmueller@suse.com>
Tested-By: NDirk Mueller <dmueller@suse.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The loop is computing one of two constants, it can be simpler to write
everything inline.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Expose VPID capability to L1. For nested guests, we don't do anything
specific for single context invalidation. Hence, only advertise support
for global context invalidation. The major benefit of nested VPID comes
from having separate vpids when switching between L1 and L2, and also
when L2's vCPUs not sched in/out on L1.
Reviewed-by: NWincy Van <fanwenyi0529@gmail.com>
Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

VPID is used to tag address space and avoid a TLB flush. Currently L0 use
the same VPID to run L1 and all its guests. KVM flushes VPID when switching
between L1 and L2.

This patch advertises VPID to the L1 hypervisor, then address space of L1
and L2 can be separately treated and avoid TLB flush when swithing between
L1 and L2. For each nested vmentry, if vpid12 is changed, reuse shadow vpid
w/ an invvpid.

Performance:

run lmbench on L2 w/ 3.5 kernel.

Context switching - times in microseconds - smaller is better
-------------------------------------------------------------------------
Host                 OS  2p/0K 2p/16K 2p/64K 8p/16K 8p/64K 16p/16K 16p/64K
                         ctxsw  ctxsw  ctxsw ctxsw  ctxsw   ctxsw   ctxsw
--------- ------------- ------ ------ ------ ------ ------ ------- -------
kernel    Linux 3.5.0-1 1.2200 1.3700 1.4500 4.7800 2.3300 5.60000 2.88000  nested VPID
kernel    Linux 3.5.0-1 1.2600 1.4300 1.5600   12.7   12.9 3.49000 7.46000  vanilla
Reviewed-by: NJan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: NWincy Van <fanwenyi0529@gmail.com>
Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add the INVVPID instruction emulation.
Reviewed-by: NWincy Van <fanwenyi0529@gmail.com>
Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Introduce __vmx_flush_tlb() to handle specific vpid.
Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Adjust allocate/free_vid so that they can be reused for the nested vpid.
Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

async_pf_execute() seems to be missing a memory barrier which might
cause the waker to not notice the waiter and miss sending a wake_up as
in the following figure.

        async_pf_execute                    kvm_vcpu_block
------------------------------------------------------------------------
spin_lock(&vcpu->async_pf.lock);
if (waitqueue_active(&vcpu->wq))
/* The CPU might reorder the test for
   the waitqueue up here, before
   prior writes complete */
                                    prepare_to_wait(&vcpu->wq, &wait,
                                      TASK_INTERRUPTIBLE);
                                    /*if (kvm_vcpu_check_block(vcpu) < 0) */
                                     /*if (kvm_arch_vcpu_runnable(vcpu)) { */
                                      ...
                                      return (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE &&
                                        !vcpu->arch.apf.halted)
                                        || !list_empty_careful(&vcpu->async_pf.done)
                                     ...
                                     return 0;
list_add_tail(&apf->link,
  &vcpu->async_pf.done);
spin_unlock(&vcpu->async_pf.lock);
                                    waited = true;
                                    schedule();
------------------------------------------------------------------------

The attached patch adds the missing memory barrier.

I found this issue when I was looking through the linux source code
for places calling waitqueue_active() before wake_up*(), but without
preceding memory barriers, after sending a patch to fix a similar
issue in drivers/tty/n_tty.c  (Details about the original issue can be
found here: https://lkml.org/lkml/2015/9/28/849).
Signed-off-by: NKosuke Tatsukawa <tatsu@ab.jp.nec.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

On real hardware, edge-triggered interrupts don't set a bit in TMR,
which means that IOAPIC isn't notified on EOI.  Do the same here.

Staying in guest/kernel mode after edge EOI is what we want for most
devices.  If some bugs could be nicely worked around with edge EOI
notifications, we should invest in a better interface.
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

KVM uses eoi_exit_bitmap to track vectors that need an action on EOI.
The problem is that IOAPIC can be reconfigured while an interrupt with
old configuration is pending and eoi_exit_bitmap only remembers the
newest configuration;  thus EOI from the pending interrupt is not
recognized.

(Reconfiguration is not a problem for level interrupts, because IOAPIC
 sends interrupt with the new configuration.)

For an edge interrupt with ACK notifiers, like i8254 timer; things can
happen in this order
 1) IOAPIC inject a vector from i8254
 2) guest reconfigures that vector's VCPU and therefore eoi_exit_bitmap
    on original VCPU gets cleared
 3) guest's handler for the vector does EOI
 4) KVM's EOI handler doesn't pass that vector to IOAPIC because it is
    not in that VCPU's eoi_exit_bitmap
 5) i8254 stops working

A simple solution is to set the IOAPIC vector in eoi_exit_bitmap if the
vector is in PIR/IRR/ISR.

This creates an unwanted situation if the vector is reused by a
non-IOAPIC source, but I think it is so rare that we don't want to make
the solution more sophisticated.  The simple solution also doesn't work
if we are reconfiguring the vector.  (Shouldn't happen in the wild and
I'd rather fix users of ACK notifiers instead of working around that.)

The are no races because ioapic injection and reconfig are locked.

Fixes: b053b2ae ("KVM: x86: Add EOI exit bitmap inference")
[Before b053b2ae, this bug happened only with APICv.]
Fixes: c7c9c56c ("x86, apicv: add virtual interrupt delivery support")
Cc: <stable@vger.kernel.org>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

After moving PIR to IRR, the interrupt needs to be delivered manually.
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Merge more important SMM fixes.

In order to get into 64-bit protected mode, you need to enable
paging while EFER.LMA=1.  For this to work, CS.L must be 0.
Currently, we load the segments before CR0 and CR4, which means
that if RSM returns into 64-bit protected mode CS.L is already 1
and everything breaks.

Luckily, CS.L=0 is always the case when executing RSM, because it
is forbidden to execute RSM from 64-bit protected mode.  Hence it
is enough to load CR0 and CR4 first, and only then the segments.

Fixes: 660a5d51
Cc: stable@vger.kernel.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Unfortunately I only noticed this after pushing.

Fixes: f0d648bd
Cc: stable@vger.kernel.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This merge brings in a couple important SMM fixes, which makes it
easier to test latest KVM with unrestricted_guest=0 and to test
the in-progress work on SMM support in the firmware.

Conflicts:
	arch/x86/kvm/x86.c

An SMI to a halted VCPU must wake it up, hence a VCPU with a pending
SMI must be considered runnable.

Fixes: 64d60670
Cc: stable@vger.kernel.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Split the huge conditional in two functions.

Fixes: 64d60670
Cc: stable@vger.kernel.org
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Otherwise, two copies (one of them never populated and thus bogus)
are allocated for the regular and SMM address spaces.  This breaks
SMM with EPT but without unrestricted guest support, because the
SMM copy of the identity page map is all zeros.

By moving the allocation to the caller we also remove the last
vestiges of kernel-allocated memory regions (not accessible anymore
in userspace since commit b74a07be, "KVM: Remove kernel-allocated
memory regions", 2010-06-21); that is a nice bonus.
Reported-by: NAlexandre DERUMIER <aderumier@odiso.com>
Cc: stable@vger.kernel.org
Fixes: 9da0e4d5Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The next patch will make x86_set_memory_region fill the
userspace_addr.  Since the struct is not used untouched
anymore, it makes sense to build it in x86_set_memory_region
directly; it also simplifies the callers.
Reported-by: NAlexandre DERUMIER <aderumier@odiso.com>
Cc: stable@vger.kernel.org
Fixes: 9da0e4d5Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvm-s390-next-20151013' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fixes for 4.4

A bunch of fixes and optimizations for interrupt and time
handling. No fix is important enough to qualify for 4.3 or
stable.

Let's factor this out and always use get_tod_clock_fast() when
reading the guest TOD.

STORE CLOCK FAST does not do serialization and, therefore, might
result in some fuzziness between different processors in a way
that subsequent calls on different CPUs might have time stamps that
are earlier. This semantics is fine though for all KVM use cases.
To make it obvious that the new function has STORE CLOCK FAST
semantics we name it kvm_s390_get_tod_clock_fast.

With this patch, we only have a handful of places were we
have to care about STP sync (using preempt_disable() logic).
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Let's move that whole logic into one function. We now always use unsigned
values when calculating the epoch (to avoid over/underflow defined).
Also, we always have to get all VCPUs out of SIE before doing the update
to avoid running differing VCPUs with different TODs.
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Nobody except early.c makes use of store_tod_clock() to handle the
cc. So if we would get a cc != 0, we would be in more trouble.

Let's replace all users with get_tod_clock(). Returning a cc
on an ioctl sounded strange either way.

We can now also easily move the get_tod_clock() call into the
preempt_disable() section. This is in fact necessary to make the
STP sync work as expected. Otherwise the host TOD could change
and we would end up with a wrong epoch calculation.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

PER events can always co-exist with other program interrupts.

For now, we always overwrite all program interrupt parameters when
injecting any type of program interrupt.

Let's handle that correctly by only overwriting the relevant portion of
the program interrupt parameters. Therefore we can now inject PER events
and ordinary program interrupts concurrently, resulting in no loss of
program interrupts. This will especially by helpful when manually detecting
PER events later - as both types might be triggered during one SIE exit.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The main reason to keep program injection in kernel separated until now
was that we were able to do some checking, if really only the owning
thread injects program interrupts (via waitqueue_active(li->wq)).

This BUG_ON was never triggered and the chances of really hitting it, if
another thread injected a program irq to another vcpu, were very small.

Let's drop this check and turn kvm_s390_inject_program_int() and
kvm_s390_inject_prog_irq() into simple inline functions that makes use of
kvm_s390_inject_vcpu().

__must_check can be dropped as they are implicitely given by
kvm_s390_inject_vcpu(), to avoid ugly long function prototypes.
Reviewed-by: NJens Freimann <jfrei@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Let's get rid of the local variable and exit directly if we found
any pending interrupt. This is not only faster, but also better
readable.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

We can remove that double check.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

No need to separate pending and floating irqs when setting interception
requests. Let's do it for all equally.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

We don't care about program event recording irqs (synchronous
program irqs) but asynchronous irqs when checking for disabled
wait. Machine checks were missing.

Let's directly switch to the functions we have for that purpose
instead of testing once again for magic bits.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

the float int structure is no longer used in __inject_vm.
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

Enable VT-d Posted-Interrtups and add a command line
parameter for it.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Acked-by: NJoerg Roedel <joro@8bytes.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch updates the Posted-Interrupts Descriptor when vCPU
is blocked.

pre-block:
- Add the vCPU to the blocked per-CPU list
- Set 'NV' to POSTED_INTR_WAKEUP_VECTOR

post-block:
- Remove the vCPU from the per-CPU list
Signed-off-by: NFeng Wu <feng.wu@intel.com>
[Concentrate invocation of pre/post-block hooks to vcpu_block. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch updates the Posted-Interrupts Descriptor when vCPU
is preempted.

sched out:
- Set 'SN' to suppress furture non-urgent interrupts posted for
the vCPU.

sched in:
- Clear 'SN'
- Change NDST if vCPU is scheduled to a different CPU
- Set 'NV' to POSTED_INTR_VECTOR
Signed-off-by: NFeng Wu <feng.wu@intel.com>
[Include asm/cpu.h to fix !CONFIG_SMP compilation. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Select IRQ_BYPASS_MANAGER for x86 when CONFIG_KVM is set
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch adds the routine to update IRTE for posted-interrupts
when guest changes the interrupt configuration.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
[Squashed in automatically generated patch from the build robot
 "KVM: x86: vcpu_to_pi_desc() can be static" - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch adds the registration/unregistration of an
irq_bypass_producer for MSI/MSIx on vfio pci devices.
Acked-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Make kvm_set_msi_irq() public, we can use this function outside.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch defines a new interface kvm_intr_is_single_vcpu(),
which can returns whether the interrupt is for single-CPU or not.

It is used by VT-d PI, since now we only support single-CPU
interrupts, For lowest-priority interrupts, if user configures
it via /proc/irq or uses irqbalance to make it single-CPU, we
can use PI to deliver the interrupts to it. Full functionality
of lowest-priority support will be added later.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>