Currently qemu/kvm on s390 uses a guest mapping that does not
allow the guest backing page table to be write-protected to
support older systems. On those older systems a host write
protection fault will be delivered to the guest.
Newer systems allow to write-protect the guest backing memory
and let the fault be delivered to the host, thus allowing COW.
Use a capability bit to tell qemu if that is possible.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Let userspace know the number of max and supported cpus for kvm on s390.
Return KVM_MAX_VCPUS (currently 64) for both values.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Lets replace the old open coded version of diag 0x44 (which relied on
compat_sched_yield) with kvm_vcpu_on_spin.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch implements the directed yield hypercall found on other
System z hypervisors. It delegates execution time to the virtual cpu
specified in the instruction's parameter.
Useful to avoid long spinlock waits in the guest.
Christian Borntraeger: moved common code in virt/kvm/
Signed-off-by: Konstantin Weitz <WEITZKON@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
The kvm_vcpu_kick function performs roughly the same funcitonality on
most all architectures, so we shouldn't have separate copies.
PowerPC keeps a pointer to interchanging waitqueues on the vcpu_arch
structure and to accomodate this special need a
__KVM_HAVE_ARCH_VCPU_GET_WQ define and accompanying function
kvm_arch_vcpu_wq have been defined. For all other architectures this
is a generic inline that just returns &vcpu->wq;
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
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Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system
Pull "Disintegrate and delete asm/system.h" from David Howells:
"Here are a bunch of patches to disintegrate asm/system.h into a set of
separate bits to relieve the problem of circular inclusion
dependencies.
I've built all the working defconfigs from all the arches that I can
and made sure that they don't break.
The reason for these patches is that I recently encountered a circular
dependency problem that came about when I produced some patches to
optimise get_order() by rewriting it to use ilog2().
This uses bitops - and on the SH arch asm/bitops.h drags in
asm-generic/get_order.h by a circuituous route involving asm/system.h.
The main difficulty seems to be asm/system.h. It holds a number of
low level bits with no/few dependencies that are commonly used (eg.
memory barriers) and a number of bits with more dependencies that
aren't used in many places (eg. switch_to()).
These patches break asm/system.h up into the following core pieces:
(1) asm/barrier.h
Move memory barriers here. This already done for MIPS and Alpha.
(2) asm/switch_to.h
Move switch_to() and related stuff here.
(3) asm/exec.h
Move arch_align_stack() here. Other process execution related bits
could perhaps go here from asm/processor.h.
(4) asm/cmpxchg.h
Move xchg() and cmpxchg() here as they're full word atomic ops and
frequently used by atomic_xchg() and atomic_cmpxchg().
(5) asm/bug.h
Move die() and related bits.
(6) asm/auxvec.h
Move AT_VECTOR_SIZE_ARCH here.
Other arch headers are created as needed on a per-arch basis."
Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that. We'll find out anything that got broken and fix it..
* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
Delete all instances of asm/system.h
Remove all #inclusions of asm/system.h
Add #includes needed to permit the removal of asm/system.h
Move all declarations of free_initmem() to linux/mm.h
Disintegrate asm/system.h for OpenRISC
Split arch_align_stack() out from asm-generic/system.h
Split the switch_to() wrapper out of asm-generic/system.h
Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
Create asm-generic/barrier.h
Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
Disintegrate asm/system.h for Xtensa
Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
Disintegrate asm/system.h for Tile
Disintegrate asm/system.h for Sparc
Disintegrate asm/system.h for SH
Disintegrate asm/system.h for Score
Disintegrate asm/system.h for S390
Disintegrate asm/system.h for PowerPC
Disintegrate asm/system.h for PA-RISC
Disintegrate asm/system.h for MN10300
...
Pull kvm updates from Avi Kivity:
"Changes include timekeeping improvements, support for assigning host
PCI devices that share interrupt lines, s390 user-controlled guests, a
large ppc update, and random fixes."
This is with the sign-off's fixed, hopefully next merge window we won't
have rebased commits.
* 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits)
KVM: Convert intx_mask_lock to spin lock
KVM: x86: fix kvm_write_tsc() TSC matching thinko
x86: kvmclock: abstract save/restore sched_clock_state
KVM: nVMX: Fix erroneous exception bitmap check
KVM: Ignore the writes to MSR_K7_HWCR(3)
KVM: MMU: make use of ->root_level in reset_rsvds_bits_mask
KVM: PMU: add proper support for fixed counter 2
KVM: PMU: Fix raw event check
KVM: PMU: warn when pin control is set in eventsel msr
KVM: VMX: Fix delayed load of shared MSRs
KVM: use correct tlbs dirty type in cmpxchg
KVM: Allow host IRQ sharing for assigned PCI 2.3 devices
KVM: Ensure all vcpus are consistent with in-kernel irqchip settings
KVM: x86 emulator: Allow PM/VM86 switch during task switch
KVM: SVM: Fix CPL updates
KVM: x86 emulator: VM86 segments must have DPL 3
KVM: x86 emulator: Fix task switch privilege checks
arch/powerpc/kvm/book3s_hv.c: included linux/sched.h twice
KVM: x86 emulator: correctly mask pmc index bits in RDPMC instruction emulation
KVM: mmu_notifier: Flush TLBs before releasing mmu_lock
...
The 16 bit value at the lowcore location with offset 0x84 is the
cpu address that is associated with an external interrupt. Rename
the field from cpu_addr to ext_cpu_addr to make that clear.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some members of kvm_memory_slot are not used by every architecture.
This patch is the first step to make this difference clear by
introducing kvm_memory_slot::arch; lpage_info is moved into it.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There are several cases were we need the control registers for
userspace. Lets also provide those in kvm_run.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When we do a stop and store status we need to pass ACTION_STOP_ON_STOP
flag to __sigp_stop().
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
In __inject_sigp_stop() do nothing when the CPU is already in stopped
state.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
On reboot the guest sends in smp_send_stop() a sigp stop to all CPUs
except for current CPU. Then the guest switches to the IPL cpu by
sending a restart to the IPL CPU, followed by a sigp stop to the
current cpu. Since restart is handled by userspace it's possible that
the restart is delivered before the old stop. This means that the IPL
CPU isn't restarted and we have no running CPUs. So let's make sure
that there is no stop action pending when we do the restart.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
In handle_stop() handle the stop bit before doing the store status as
described for "Stop and Store Status" in the Principles of Operation.
We have to give up the local_int.lock before calling kvm store status
since it calls gmap_fault() which might sleep. Since local_int.lock
only protects local_int.* and not guest memory we can give up the lock.
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
commit 7eef87dc99 (KVM: s390: fix
register setting) added a load of the floating point control register
to the KVM_SET_FPU path. Lets make sure that the fpc is valid.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch adds the access registers to the kvm_run structure.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch adds the general purpose registers to the kvm_run structure.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Add the prefix register to the synced register field in kvm_run.
While we need the prefix register most of the time read-only, this
patch also adds handling for guest dirtying of the prefix register.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There are several places in the kvm module, which set the prefix register.
Since we need to flush the cpu, lets combine this operation into a helper
function. This helper will also explicitely mask out the unused bits.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch fixes the return code of kvm_arch_vcpu_ioctl in case
of an unkown ioctl number.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch announces a new capability KVM_CAP_S390_UCONTROL that
indicates that kvm can now support virtual machines that are
controlled by userspace.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch makes sure user controlled virtual machines do not use a
system control area (sca). This is needed in order to create
virtual machines with more cpus than the size of the sca [64].
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch allows the user to fault in pages on a virtual cpus
address space for user controlled virtual machines. Typically this
is superfluous because userspace can just create a mapping and
let the kernel's page fault logic take are of it. There is one
exception: SIE won't start if the lowcore is not present. Normally
the kernel takes care of this [handle_validity() in
arch/s390/kvm/intercept.c] but since the kernel does not handle
intercepts for user controlled virtual machines, userspace needs to
be able to handle this condition.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch disables the in-kernel interrupt stack for KVM virtual
machines that are controlled by user. Userspace has to take care
of handling interrupts on its own.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch disables in-kernel handling of SIE intercepts for user
controlled virtual machines. All intercepts are passed to userspace
via KVM_EXIT_SIE exit reason just like SIE intercepts that cannot be
handled in-kernel for regular KVM guests.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch exports the s390 SIE hardware control block to userspace
via the mapping of the vcpu file descriptor. In order to do so,
a new arch callback named kvm_arch_vcpu_fault is introduced for all
architectures. It allows to map architecture specific pages.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch introduces a new exit reason in the kvm_run structure
named KVM_EXIT_S390_UCONTROL. This exit indicates, that a virtual cpu
has regognized a fault on the host page table. The idea is that
userspace can handle this fault by mapping memory at the fault
location into the cpu's address space and then continue to run the
virtual cpu.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch introduces two ioctls for virtual cpus, that are only
valid for kernel virtual machines that are controlled by userspace.
Each virtual cpu has its individual address space in this mode of
operation, and each address space is backed by the gmap
implementation just like the address space for regular KVM guests.
KVM_S390_UCAS_MAP allows to map a part of the user's virtual address
space to the vcpu. Starting offset and length in both the user and
the vcpu address space need to be aligned to 1M.
KVM_S390_UCAS_UNMAP can be used to unmap a range of memory from a
virtual cpu in a similar way.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch introduces a new config option for user controlled kernel
virtual machines. It introduces a parameter to KVM_CREATE_VM that
allows to set bits that alter the capabilities of the newly created
virtual machine.
The parameter is passed to kvm_arch_init_vm for all architectures.
The only valid modifier bit for now is KVM_VM_S390_UCONTROL.
This requires CAP_SYS_ADMIN privileges and creates a user controlled
virtual machine on s390 architectures.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
KVM on s390 always had a sync mmu. Any mapping change in userspace
mapping was always reflected immediately in the guest mapping.
- In older code the guest mapping was just an offset
- In newer code the last level page table is shared
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There is a potential host deadlock in the tprot intercept handling.
We must not hold the mmap semaphore while resolving the guest
address. If userspace is remapping, then the memory detection in
the guest is broken anyway so we can safely separate the
address translation from walking the vmas.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
SIGP sense running may cause an intercept on higher level
virtualization, so handle it by checking the CPUSTAT_RUNNING flag.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
CPUSTAT_RUNNING was implemented signifying that a vcpu is not stopped.
This is not, however, what the architecture says: RUNNING should be
set when the host is acting on the behalf of the guest operating
system.
CPUSTAT_RUNNING has been changed to be set in kvm_arch_vcpu_load()
and to be unset in kvm_arch_vcpu_put().
For signifying stopped state of a vcpu, a host-controlled bit has
been used and is set/unset basically on the reverse as the old
CPUSTAT_RUNNING bit (including pushing it down into stop handling
proper in handle_stop()).
Cc: stable@kernel.org
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Linux on System z uses a ballooner based on diagnose 0x10. (aka as
collaborative memory management). This patch implements diagnose
0x10 on the guest address space.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Implement sigp external call, which might be required for guests that
issue an external call instead of an emergency signal for IPI.
This fixes an issue with "KVM: unknown SIGP: 0x02" when booting
such an SMP guest.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
KVM common code does vcpu_load prior to calling our arch ioctls and
vcpu_put after we're done here. Via the kvm_arch_vcpu_load/put
callbacks we do load the fpu and access register state into the
processor, which saves us moving the state on every SIE exit the
kernel handles. However this breaks register setting from userspace,
because of the following sequence:
1a. vcpu load stores userspace register content
1b. vcpu load loads guest register content
2. kvm_arch_vcpu_ioctl_set_fpu/sregs updates saved guest register content
3a. vcpu put stores the guest registers and overwrites the new content
3b. vcpu put loads the userspace register set again
This patch loads the new guest register state into the cpu, so that the correct
(new) set of guest registers will be stored in step 3a.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch fixes the return value of kvm_arch_init_vm in case a memory
allocation goes wrong.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
We use the cpu id provided by userspace as array index here. Thus we
clearly need to check it first. Ooops.
CC: <stable@vger.kernel.org>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
598841ca99 ([S390] use gmap address
spaces for kvm guest images) changed kvm on s390 to use a separate
address space for kvm guests. We can now put KVM guests anywhere
in the user address mode with a size up to 8PB - as long as the
memory is 1MB-aligned. This change was done without KVM extension
capability bit.
The change was added after 3.0, but we still have a chance to add
a feature bit before 3.1 (keeping the releases in a sane state).
We use number 71 to avoid collisions with other pending kvm patches
as requested by Alexander Graf.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Avi Kivity <avi@redhat.com>
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
598841ca99 ([S390] use gmap address
spaces for kvm guest images) changed kvm to use a separate address
space for kvm guests. This address space was switched in __vcpu_run
In some cases (preemption, page fault) there is the possibility that
this address space switch is lost.
The typical symptom was a huge amount of validity intercepts or
random guest addressing exceptions.
Fix this by doing the switch in sie_loop and sie_exit and saving the
address space in the gmap structure itself. Also use the preempt
notifier.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
SIGP emerg needs to pass the source vpu adress into __LC_CPU_ADDRESS of the
target guest.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch removes the mmu reload logic for kvm on s390. Via Martin's
new gmap interface, we can safely add or remove memory slots while
guest CPUs are in-flight. Thus, the mmu reload logic is not needed
anymore.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch removes kvm-s390 internal assumption of a linear mapping
of guest address space to user space. Previously, guest memory was
translated to user addresses using a fixed offset (gmsor). The new
code uses gmap_fault to resolve guest addresses.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch switches kvm from using (Qemu's) user address space to
Martin's gmap address space. This way QEMU does not have to use a
linker script in order to fit large guests at low addresses in its
address space.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The entry to / exit from sie has subtle dependencies to the first level
interrupt handler. Move the sie assembler code to entry64.S and replace
the SIE_HOOK callback with a test and the new _TIF_SIE bit.
In addition this patch fixes several problems in regard to the check for
the_TIF_EXIT_SIE bits. The old code checked the TIF bits before executing
the interrupt handler and it only modified the instruction address if it
pointed directly to the sie instruction. In both cases it could miss
a TIF bit that normally would cause an exit from the guest and would
reenter the guest context.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When running a kvm guest we can get intercepts for tprot, if the host
page table is read-only or not populated. This patch implements the
most common case (linux memory detection).
This also allows host copy on write for guest memory on newer systems.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
virtio has been so far used only in the context of virtualization,
and the virtio Kconfig was sourced directly by the relevant arch
Kconfigs when VIRTUALIZATION was selected.
Now that we start using virtio for inter-processor communications,
we need to source the virtio Kconfig outside of the virtualization
scope too.
Moreover, some architectures might use virtio for both virtualization
and inter-processor communications, so directly sourcing virtio
might yield unexpected results due to conflicting selections.
The simple solution offered by this patch is to always source virtio's
Kconfig in drivers/Kconfig, and remove it from the appropriate arch
Kconfigs. Additionally, a virtio menu entry has been added so virtio
drivers don't show up in the general drivers menu.
This way anyone can use virtio, though it's arguably less accessible
(and neat!) for virtualization users now.
Note: some architectures (mips and sh) seem to have a VIRTUALIZATION
menu merely for sourcing virtio's Kconfig, so that menu is removed too.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
commit 9ff4cfb3fc ([S390] kvm-390: Let
kernel exit SIE instruction on work) fixed a problem of commit
commit cd3b70f5d4 ([S390] virtualization
aware cpu measurement) but uncovered another one.
If a kvm guest accesses guest real memory that doesnt exist, the
page fault handler calls the sie hook, which then rewrites
the return psw from sie_inst to either sie_exit or sie_reenter.
On return, the page fault handler will then detect the wrong access
as a kernel fault causing a kernel oops in sie_reenter or sie_exit.
We have to add these two addresses to the exception table to allow
graceful exits.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
From: Christian Borntraeger <borntraeger@de.ibm.com>
This patch fixes the sie exit on interrupts. The low level
interrupt handler returns to the PSW address in pt_regs and not
to the PSW address in the lowcore.
Without this fix a cpu bound guest might never leave guest state
since the host interrupt handler would blindly return to the
SIE instruction, even on need_resched and friends.
Cc: stable@kernel.org
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Replace EXTRA_CFLAGS with ccflags-y.
Signed-off-by: matt mooney <mfm@muteddisk.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
* 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits)
KVM: Initialize fpu state in preemptible context
KVM: VMX: when entering real mode align segment base to 16 bytes
KVM: MMU: handle 'map_writable' in set_spte() function
KVM: MMU: audit: allow audit more guests at the same time
KVM: Fetch guest cr3 from hardware on demand
KVM: Replace reads of vcpu->arch.cr3 by an accessor
KVM: MMU: only write protect mappings at pagetable level
KVM: VMX: Correct asm constraint in vmcs_load()/vmcs_clear()
KVM: MMU: Initialize base_role for tdp mmus
KVM: VMX: Optimize atomic EFER load
KVM: VMX: Add definitions for more vm entry/exit control bits
KVM: SVM: copy instruction bytes from VMCB
KVM: SVM: implement enhanced INVLPG intercept
KVM: SVM: enhance mov DR intercept handler
KVM: SVM: enhance MOV CR intercept handler
KVM: SVM: add new SVM feature bit names
KVM: cleanup emulate_instruction
KVM: move complete_insn_gp() into x86.c
KVM: x86: fix CR8 handling
KVM guest: Fix kvm clock initialization when it's configured out
...
IA64 support forces us to abstract the allocation of the kvm structure.
But instead of mixing this up with arch-specific initialization and
doing the same on destruction, split both steps. This allows to move
generic destruction calls into generic code.
It also fixes error clean-up on failures of kvm_create_vm for IA64.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Make use of def_bool and def_tristate where possible and add sensible
defaults to the config symbols where applicable. This shortens the
defconfig file by another ~40 lines.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Store the facility list once at system startup with stfl/stfle and
reuse the result for all facility tests.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Enable PFPO, floating point extension, distinct-operands,
fast-BCR-serialization, high-word, interlocked-access, load/store-
on-condition, and population-count facilities for guests.
(bits 37, 44 and 45).
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
As advertised in feature-removal-schedule.txt. Equivalent support is provided
by overlapping memory regions.
Signed-off-by: Avi Kivity <avi@redhat.com>
Newer (guest) kernels use sigp sense running in their spinlock
implementation to check if the other cpu is running before yielding
the processor. This revealed some wrong guest settings, causing
unnecessary exits for every sigp sense running.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Now that all arch specific ioctls have centralized locking, it is easy to
move it to the central dispatcher.
Signed-off-by: Avi Kivity <avi@redhat.com>
All vcpu ioctls need to be locked, so instead of locking each one specifically
we lock at the generic dispatcher.
This patch only updates generic ioctls and leaves arch specific ioctls alone.
Signed-off-by: Avi Kivity <avi@redhat.com>
The containing function is called from several places. At one of them, in
the function __sigp_stop, the spin lock &fi->lock is held.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@gfp exists@
identifier fn;
position p;
@@
fn(...) {
... when != spin_unlock
when any
GFP_KERNEL@p
... when any
}
@locked@
identifier gfp.fn;
@@
spin_lock(...)
... when != spin_unlock
fn(...)
@depends on locked@
position gfp.p;
@@
- GFP_KERNEL@p
+ GFP_ATOMIC
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add missing GFP flag to memory allocations. The part in cio only
changes a comment.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This config option enables or disables three single instructions
which aren't expensive. This is too fine grained.
Besided that everybody who uses kvm would enable it anyway in order
to debug performance problems.
Just remove it.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'kvm-updates/2.6.35' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (269 commits)
KVM: x86: Add missing locking to arch specific vcpu ioctls
KVM: PPC: Add missing vcpu_load()/vcpu_put() in vcpu ioctls
KVM: MMU: Segregate shadow pages with different cr0.wp
KVM: x86: Check LMA bit before set_efer
KVM: Don't allow lmsw to clear cr0.pe
KVM: Add cpuid.txt file
KVM: x86: Tell the guest we'll warn it about tsc stability
x86, paravirt: don't compute pvclock adjustments if we trust the tsc
x86: KVM guest: Try using new kvm clock msrs
KVM: x86: export paravirtual cpuid flags in KVM_GET_SUPPORTED_CPUID
KVM: x86: add new KVMCLOCK cpuid feature
KVM: x86: change msr numbers for kvmclock
x86, paravirt: Add a global synchronization point for pvclock
x86, paravirt: Enable pvclock flags in vcpu_time_info structure
KVM: x86: Inject #GP with the right rip on efer writes
KVM: SVM: Don't allow nested guest to VMMCALL into host
KVM: x86: Fix exception reinjection forced to true
KVM: Fix wallclock version writing race
KVM: MMU: Don't read pdptrs with mmu spinlock held in mmu_alloc_roots
KVM: VMX: enable VMXON check with SMX enabled (Intel TXT)
...
vmx and svm vcpus have different contents and therefore may have different
alignmment requirements. Let each specify its required alignment.
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch fixed possible memory leak in kvm_arch_vcpu_create()
under s390, which would happen when kvm_arch_vcpu_create() fails.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
Use the SPP instruction to set a tag on entry to / exit of the virtual
machine context. This allows the cpu measurement facility to distinguish
the samples from the host and the different guests.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
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>
Use asm offsets to make sure the offset defines to struct _lowcore and
its layout don't get out of sync.
Also add a BUILD_BUG_ON() which checks that the size of the structure
is sane.
And while being at it change those sites which use odd casts to access
the current lowcore. These should use S390_lowcore instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
ENOTSUPP is not supposed to leak to userspace so lets just use
EOPNOTSUPP everywhere.
Doesn't fix a bug, but makes future reviews easier.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove support to be able to dump 31 bit systems with a 64 bit dumper.
This is mostly useless since no distro ships 31 bit kernels together
with a 64 bit dumper.
We also get rid of a bit of hacky code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
kvm_handle_sie_intercept uses a jump table to get the intercept handler
for a SIE intercept. Static code analysis revealed a potential problem:
the intercept_funcs jump table was defined to contain (0x48 >> 2) entries,
but we only checked for code > 0x48 which would cause an off-by-one
array overflow if code == 0x48.
Use the compiler and ARRAY_SIZE to automatically set the limits.
Cc: stable@kernel.org
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
What it is: vhost net is a character device that can be used to reduce
the number of system calls involved in virtio networking.
Existing virtio net code is used in the guest without modification.
There's similarity with vringfd, with some differences and reduced scope
- uses eventfd for signalling
- structures can be moved around in memory at any time (good for
migration, bug work-arounds in userspace)
- write logging is supported (good for migration)
- support memory table and not just an offset (needed for kvm)
common virtio related code has been put in a separate file vhost.c and
can be made into a separate module if/when more backends appear. I used
Rusty's lguest.c as the source for developing this part : this supplied
me with witty comments I wouldn't be able to write myself.
What it is not: vhost net is not a bus, and not a generic new system
call. No assumptions are made on how guest performs hypercalls.
Userspace hypervisors are supported as well as kvm.
How it works: Basically, we connect virtio frontend (configured by
userspace) to a backend. The backend could be a network device, or a tap
device. Backend is also configured by userspace, including vlan/mac
etc.
Status: This works for me, and I haven't see any crashes.
Compared to userspace, people reported improved latency (as I save up to
4 system calls per packet), as well as better bandwidth and CPU
utilization.
Features that I plan to look at in the future:
- mergeable buffers
- zero copy
- scalability tuning: figure out the best threading model to use
Note on RCU usage (this is also documented in vhost.h, near
private_pointer which is the value protected by this variant of RCU):
what is happening is that the rcu_dereference() is being used in a
workqueue item. The role of rcu_read_lock() is taken on by the start of
execution of the workqueue item, of rcu_read_unlock() by the end of
execution of the workqueue item, and of synchronize_rcu() by
flush_workqueue()/flush_work(). In the future we might need to apply
some gcc attribute or sparse annotation to the function passed to
INIT_WORK(). Paul's ack below is for this RCU usage.
(Includes fixes by Alan Cox <alan@linux.intel.com>,
David L Stevens <dlstevens@us.ibm.com>,
Chris Wright <chrisw@redhat.com>)
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce user_mode to replace the two variables switch_amode and
s390_noexec. There are three valid combinations of the old values:
1) switch_amode == 0 && s390_noexec == 0
2) switch_amode == 1 && s390_noexec == 0
3) switch_amode == 1 && s390_noexec == 1
They get replaced by
1) user_mode == HOME_SPACE_MODE
2) user_mode == PRIMARY_SPACE_MODE
3) user_mode == SECONDARY_SPACE_MODE
The new kernel parameter user_mode=[primary,secondary,home] lets
you choose the address space mode the user space processes should
use. In addition the CONFIG_S390_SWITCH_AMODE config option
is removed.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch corrects the checking of the new address for the prefix register.
On s390, the prefix register is used to address the cpu's lowcore (address
0...8k). This check is supposed to verify that the memory is readable and
present.
copy_from_guest is a helper function, that can be used to read from guest
memory. It applies prefixing, adds the start address of the guest memory in
user, and then calls copy_from_user. Previous code was obviously broken for
two reasons:
- prefixing should not be applied here. The current prefix register is
going to be updated soon, and the address we're looking for will be
0..8k after we've updated the register
- we're adding the guest origin (gmsor) twice: once in subject code
and once in copy_from_guest
With kuli, we did not hit this problem because (a) we were lucky with
previous prefix register content, and (b) our guest memory was mmaped
very low into user address space.
Cc: stable@kernel.org
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch moves s390 processor status word into the base kvm_run
struct and keeps it up-to date on all userspace exits.
The userspace ABI is broken by this, however there are no applications
in the wild using this. A capability check is provided so users can
verify the updated API exists.
Cc: stable@kernel.org
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
X86 CPUs need to have some magic happening to enable the virtualization
extensions on them. This magic can result in unpleasant results for
users, like blocking other VMMs from working (vmx) or using invalid TLB
entries (svm).
Currently KVM activates virtualization when the respective kernel module
is loaded. This blocks us from autoloading KVM modules without breaking
other VMMs.
To circumvent this problem at least a bit, this patch introduces on
demand activation of virtualization. This means, that instead
virtualization is enabled on creation of the first virtual machine
and disabled on destruction of the last one.
So using this, KVM can be easily autoloaded, while keeping other
hypervisors usable.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
commit 628eb9b8a8
KVM: s390: streamline memslot handling
introduced kvm_s390_vcpu_get_memsize. This broke guests >=4G, since this
function returned an int.
This patch changes the return value to a long.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from
interface between general code and arch code. kvm_arch_vcpu_runnable()
checks for interrupts instead.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch relocates the variables kvm-s390 uses to track guest mem addr/size.
As discussed dropping the variables at struct kvm_arch level allows to use the
common vcpu->request based mechanism to reload guest memory if e.g. changes
via set_memory_region.
The kick mechanism introduced in this series is used to ensure running vcpus
leave guest state to catch the update.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If signal pending is true we exit without updating kvm_run, userspace
currently just does nothing and jumps to kvm_run again.
Since we did not set an exit_reason we might end up with a random one
(whatever was the last exit). Therefore it was possible to e.g. jump to
the psw position the last real interruption set.
Setting the INTR exit reason ensures that no old psw data is swapped
in on reentry.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
To ensure vcpu's come out of guest context in certain cases this patch adds a
s390 specific way to kick them out of guest context. Currently it kicks them
out to rerun the vcpu_run path in the s390 code, but the mechanism itself is
expandable and with a new flag we could also add e.g. kicks to userspace etc.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
